Draft Comprehensive Conservation Plan and Environmental Assessment Felsenthal and Overflow National Wildlife Refuges

              DRAFT COMPREHENSIVE CONSERVATION PLAN
AND ENVIRONMENTAL ASSESSMENT
FELSENTHAL AND OVERFLOW NATIONAL WILDLIFE REFUGES
Ashley, Bradley, Desha, and Union Counties, Arkansas
U.S. Department of the Interior
Fish and Wildlife Service
Southeast Region
Atlanta, Georgia
May 2010
Felsenthal and Overflow National Wildlife Refuges
Table of Contents i
TABLE OF CONTENTS
SECTION A. DRAFT COMPREHENSIVE CONSERVATION PLAN
I. BACKGROUND ................................................................................................................................ 1
Introduction .................................................................................................................................. 1
Purpose and Need for the Plan .................................................................................................... 1
U.S. Fish and Wildlife Service ...................................................................................................... 1
National Wildlife Refuge System .................................................................................................. 2
Legal and Policy Context .............................................................................................................. 4
National and International Conservation Plans and Initiatives ..................................................... 5
Relationship To State Wildlife Agency .......................................................................................... 6
II. REFUGE OVERVIEW ....................................................................................................................... 9
Introduction .................................................................................................................................. 9
Refuge History and Purpose ...................................................................................................... 12
Special Designations .................................................................................................................. 14
Ecosystem Context ..................................................................................................................... 16
Regional Conservation Plans and Initiatives .............................................................................. 21
Ecological Threats and Problems ............................................................................................... 22
Physical Resources .................................................................................................................... 26
Climate .............................................................................................................................. 26
Climate Change and Global Warming ............................................................................... 26
Geology and Topography .................................................................................................. 28
Soils ................................................................................................................................. 30
Hydrology and Water Quality ............................................................................................ 31
Air Quality .......................................................................................................................... 34
Biological Resources .................................................................................................................. 36
Habitat ............................................................................................................................... 36
Wildlife ............................................................................................................................... 43
Cultural Resources ..................................................................................................................... 47
Historical Background ....................................................................................................... 47
Socioeconomic Environment ...................................................................................................... 49
Regional Demographics and Economy ............................................................................. 49
Refuge Administration and Management ................................................................................... 50
Land Protection and Conservation .................................................................................... 50
Visitor Services ................................................................................................................. 54
Personnel, Operations, and Maintenance ......................................................................... 61
III. PLAN DEVELOPMENT ................................................................................................................. 63
Summary of Issues, Concerns, and Opportunities ..................................................................... 63
Fish and Wildlife Population Management - Felsenthal and Overflow NWRs .................. 64
Habitat Management - Felsenthal ..................................................................................... 65
Habitat Management - Overflow ....................................................................................... 66
Resource Protection - Felsenthal and Overflow ................................................................ 66
Visitor Services - Felsenthal and Overflow ....................................................................... 66
Refuge Administration – Felsenthal and Overflow ............................................................ 68
ii Felsenthal and Overflow National Wildlife Refuges
IV. MANAGEMENT DIRECTION ........................................................................................................ 69
Introduction ............................................................................................................................... 69
Vision ........................................................................................................................................ 69
Goals, Objectives, and Strategies .............................................................................................. 70
Fish and Wildlife Population Management........................................................................ 70
Habitat Management......................................................................................................... 91
Visitor Services ............................................................................................................... 118
Resource Protection and Refuge Administration ............................................................ 129
V. PLAN IMPLEMENTATION ........................................................................................................... 135
Introduction .............................................................................................................................. 135
Proposed Projects .................................................................................................................... 135
Fish And Wildlife Population Management ..................................................................... 135
Habitat Management....................................................................................................... 136
Resource Protection ....................................................................................................... 139
Visitor Services ............................................................................................................... 139
Funding and Personnel ............................................................................................................ 140
Partnership and Volunteer Opportunities ................................................................................. 144
Step-down Management Plans ................................................................................................ 144
Monitoring and Adaptive Management ..................................................................................... 145
Plan Review and Revision........................................................................................................ 146
SECTION B. ENVIRONMENTAL ASSESSMENT
I. BACKGROUND ............................................................................................................................. 165
Introduction .............................................................................................................................. 165
Purpose and Need for Action ................................................................................................... 165
Decision Framework................................................................................................................. 166
Planning Study Area ................................................................................................................ 166
Authority, Legal Compliance, and Compatibility ....................................................................... 167
Compatibility ................................................................................................................... 167
Public Involvement and the Planning Process ......................................................................... 167
II. AFFECTED ENVIRONMENT ....................................................................................................... 169
III. DESCRIPTION OF ALTERNATIVES .......................................................................................... 171
Formulation of Alternatives....................................................................................................... 171
Description of Alternatives - Felsenthal NWR .......................................................................... 171
Alternative A: Current Management (No Action) ............................................................. 171
Alternative B: Enhanced Biological Management and Visitor Services (Proposed
Alternative) ...................................................................................................................... 172
Alternative C: Enhanced Biological Management ........................................................... 173
Features Common to all Felsenthal NWR Alternatives ............................................................ 174
Comparison of Alternatives – Felsenthal NWR ........................................................................ 175
Description of Alternatives - Overflow NWR ............................................................................. 193
Alternative A: Current Management (No Action) ............................................................. 193
Alternative B: Enhanced Biological Management and Visitor Services (Proposed
Alternative) ...................................................................................................................... 194
Table of Contents iii
Alternative C: Enhanced Biological Management ........................................................... 194
Features Common to all Overflow NWR Alternatives ............................................................... 195
Comparison of Alternatives – Overflow NWR ........................................................................... 196
Alternatives Considered But Eliminated From Further Analysis ............................................... 217
IV. ENVIRONMENTAL CONSEQUENCES ...................................................................................... 219
Overview .................................................................................................................................. 219
Effects Common to All Alternatives .......................................................................................... 219
Environmental Justice ..................................................................................................... 219
Climate Change .............................................................................................................. 219
Other Management ......................................................................................................... 222
Land Acquisition .............................................................................................................. 222
Cultural Resources .......................................................................................................... 223
Refuge Revenue-Sharing ................................................................................................ 223
Other Effects ................................................................................................................... 223
Summary of Effects by Alternative ........................................................................................... 224
Alternative A: Current Management (No action) ............................................................. 224
Alternative B: Enhanced Biological Management and Visitor Services (Proposed
Alternative) ...................................................................................................................... 227
Alternative C: Enhanced Biological Management ........................................................... 229
Unavoidable Impacts and Mitigation Measures ........................................................................ 296
Water Quality from Soil Disturbance and Use of Herbicides ........................................... 296
Wildlife Disturbance ....................................................................................................... 296
Vegetation Disturbance ................................................................................................... 297
User Group Conflicts ....................................................................................................... 297
Effects on Adjacent Landowners ..................................................................................... 297
Land Ownership and Site Development .......................................................................... 297
Cumulative Impacts .................................................................................................................. 298
Direct and Indirect Effects or Impacts ....................................................................................... 298
Short-term Uses versus Long-term Productivity ....................................................................... 299
V. CONSULTATION AND COORDINATION .................................................................................... 301
Overview .................................................................................................................................. 301
APPENDICES
APPENDIX A. GLOSSARY ............................................................................................................... 305
APPENDIX B. REFERENCES AND LITERATURE CITATIONS ...................................................... 315
APPENDIX C. RELEVANT LEGAL MANDATES AND EXECUTIVE ORDERS ............................... 323
APPENDIX D. PUBLIC INVOLVEMENT .......................................................................................... 337
Summary of Public Scoping Comments ................................................................................... 337
APPENDIX E. APPROPRIATE USE DETERMINATIONS ............................................................... 343
iv Felsenthal and Overflow National Wildlife Refuges
APPENDIX F. COMPATIBILITY DETERMINATIONS ...................................................................... 367
Felsenthal National Wildlife Refuge Compatibility Determinations ........................................... 367
Overflow National Wildlife Refuge Compatibility Determinations ............................................. 396
APPENDIX G. INTRA-SERVICE SECTION 7 BIOLOGICAL EVALUATION ................................... 415
APPENDIX H. WILDERNESS REVIEW ........................................................................................... 419
APPENDIX I. REFUGE BIOTA ......................................................................................................... 421
APPENDIX J. LIST OF PREPARERS .............................................................................................. 445
Table of Contents v
LIST OF FIGURES
Figure 1. Location of Felsenthal and Overflow National Wildlife Refuges and the
Oakwood Unit. .................................................................................................................... 7
Figure 2. Acquisition boundary of Felsenthal National Wildlife Refuge............................................. 10
Figure 3. Acquisition boundary of Overflow National Wildlife Refuge. .............................................. 11
Figure 4. Acquisition boundary of Oakwood Unit of Overflow National Wildlife Refuge. .................. 15
Figure 5. Lower Mississippi River Ecosystem. .................................................................................. 17
Figure 6. USFWS-designated ecosystems in the U.S., showing the Lower Mississippi River
Watershed Ecosystem (#27). ............................................................................................ 20
Figure 7. General habitat types on Felsenthal National Wildlife Refuge. .......................................... 37
Figure 8. General habitat types on Overflow National Wildlife Refuge. ............................................ 39
Figure 9. General habitat types on the Oakwood Unit. ..................................................................... 44
Figure 10. Locations of public use areas on Felsenthal National Wildlife Refuge. ............................. 56
Figure 11. Locations of public use areas on Overflow National Wildlife Refuge. ................................ 59
Figure 12. Current organization chart. .............................................................................................. 141
Figure 13. Proposed organization chart. ........................................................................................... 142
vi Felsenthal and Overflow National Wildlife Refuges
LIST OF TABLES
Table 1. Climatological normals for the years 1971-2000 from the National Weather
Service station at El Dorado Airport (032300).................................................................... 27
Table 2. Climatological normals for the years 1971-2000 from the National Weather
Service station at Crossett (031730). ................................................................................. 27
Table 3. Arkansas ambient air monitoring data. ............................................................................... 35
Table 4. Felsenthal NWR habitat types and their acreages. ............................................................ 36
Table 5. Overflow NWR habitat types and their acreages. ............................................................... 38
Table 6. Demographics and socioeconomics for the Felsenthal and Overflow NWRs area. ........... 51
Table 7. Felsenthal NWR recreation visits in 2004. .......................................................................... 52
Table 8. Felsenthal NWR visitor recreation expenditures in 2004. ................................................... 52
Table 9. Activities in Arkansas by U.S. residents, 2006. .................................................................. 53
Table 10. Types of hunts provided during the 2007-2008 hunting season at Felsenthal
National Wildlife Refuge. .................................................................................................... 60
Table 11. Summary of projects. ........................................................................................................ 143
Table 12. Additional personnel identified to implement the CCP for the South Arkansas
Refuge Complex. ............................................................................................................. 144
Table 13. Refuge step-down management plans related to the goals and objectives
of the comprehensive conservation plan. ........................................................................ 145
Table 14. Felsenthal NWR – Managing for climate change through habitat and
species management. ...................................................................................................... 147
Table 15. Overflow NWR – Managing for climate change through habitat and
species management. ...................................................................................................... 156
Table 16. Comparison of alternatives by management issues for Felsenthal
National Wildlife Refuge. .................................................................................................. 176
Table 17. Comparison of alternatives by management issues for Overflow
National Wildlife Refuge. .................................................................................................. 197
Table 18. Summary of environmental effects by alternative, Felsenthal
National Wildlife Refuge. .................................................................................................. 232
Table 19. Summary of environmental effects by alternative, Overflow
National Wildlife Refuge. .................................................................................................. 264
Draft Comprehensive Conservation Plan 1
SECTION A. DRAFT COMPREHENSIVE CONSERVATION PLAN
I. Background
INTRODUCTION
The U.S. Fish and Wildlife Service (Service) has prepared this Draft Comprehensive
Conservation Plan and Evironmental Assessment for Felsenthal and Overflow national wildlife
refuges to guide their management actions and direction over the next 15 years. Fish and
wildlife conservation will receive first priority in refuge management; wildlife-dependent
recreation will be allowed and encouraged as long as it is compatible with, and does not detract
from, the mission of the two refuges or the purposes for which they were established.
A planning team developed a range of alternatives that best meet the goals and objectives of the
two refuges and that could be implemented within a 15-year planning period. This draft
comprehensive conservation plan and environmental assessment describes the Service’s proposed
plan, as well as several other alternatives that were considered and their effects on the environment.
The draft plan and environmental assessment is being made available to state and federal
government agencies, conservation partners, and the general public for review and comment.
Comments from this public review will be considered in the development of the final plan.
PURPOSE AND NEED FOR THE PLAN
The purpose of the plan is to develop a proposed action that best achieves the purposes of the
two refuges; attains the vision and goals developed for the refuges; contributes to the mission of
the National Wildlife Refuge System; addresses key problems, issues and relevant mandates;
and is consistent with sound principles of fish and wildlife management.
Specifically, the plan is needed to:
 provide a clear statement of the refuges’ management direction;
 provide refuge neighbors, visitors, and government officials with an understanding of the
Service’s management actions on and around the refuges;
 ensure that the Service’s management actions, including land protection and
recreation/education programs, are consistent with the mandates of the National Wildlife
Refuge System; and
 provide a basis for the development of budget requests for operations, maintenance,
and capital improvement needs.
U.S. FISH AND WILDLIFE SERVICE
The Service traces its roots to 1871 through the establishment of the Commission of Fisheries
involved with research and fish culture. The once-independent commission was renamed the
Bureau of Fisheries and placed under the Department of Commerce and Labor in 1903.
The Service also traces its roots to 1886 with the establishment of a Division of Economic
Ornithology and Mammalogy in the Department of Agriculture. Research on the relationship of
birds and animals to agriculture shifted to delineation of the range of plants and animals, so the
name was changed to the Division of the Biological Survey in 1896.
2 Felsenthal and Overflow National Wildlife Refuges
The Department of Commerce’s Bureau of Fisheries was combined with the Department of
Agriculture’s Bureau of Biological Survey on June 30, 1940, and transferred to the Department
of the Interior as the Fish and Wildlife Service. The name was changed to the Bureau of Sport
Fisheries and Wildlife in 1956 and finally to the U.S. Fish and Wildlife Service in 1974.
The U.S. Fish and Wildlife Service, working with others, is responsible for conserving,
protecting, and enhancing fish and wildlife and their habitats for the continuing benefit of the
American people through federal programs relating to migratory birds, endangered species,
interjurisdictional fish and marine mammals, and inland sport fisheries (142 DM 1.1).
As part of its mission, the Service manages more than 540 national wildlife refuges covering
over 95 million acres. These areas comprise the National Wildlife Refuge System, the world’s
largest collection of lands set aside specifically for fish and wildlife. The majority of these lands,
77 million acres, are in Alaska. The remaining acres are spread across the other 49 states and
several United States territories. In addition to refuges, the Service manages thousands of
small wetlands, national fish hatcheries, 64 fishery resource offices, and 78 ecological services
field stations. The Service enforces federal wildlife laws; administers the Endangered Species
Act; manages migratory bird populations; restores nationally significant fisheries; conserves and
restores wildlife habitat; and helps foreign governments with their conservation efforts. It also
oversees the Federal Aid program that distributes hundreds of millions of dollars in excise taxes
on fishing and hunting equipment to state fish and wildlife agencies.
NATIONAL WILDLIFE REFUGE SYSTEM
The mission of the National Wildlife Refuge System, as defined by the National Wildlife Refuge
System Improvement Act of 1997, is:
... to administer a national network of lands and waters for the conservation, management,
and where appropriate, restoration of the fish, wildlife and plant resources and their habitats
within the United States for the benefit of present and future generations of Americans.
The National Wildlife Refuge System Improvement Act of 1997 established, for the first time, a
clear legislative mission of wildlife conservation for the National Wildlife Refuge System.
Actions were initiated in 1997 to comply with the direction of this new legislation, including an
effort to complete comprehensive conservation plans for all refuges. These plans, which are
completed with full public involvement, help guide the future management of refuges by
establishing natural resources and recreation/education programs. Consistent with this Act,
approved plans will serve as the guidelines for refuge management for the next 15 years. The
Act states that each refuge shall be managed to:
 fulfill the mission of the National Wildlife Refuge System;
 fulfill the individual purposes of each refuge;
 consider the needs of wildlife first;
 fulfill requirements of comprehensive conservation plans that are prepared for each unit
of the Refuge System;
 maintain the biological integrity, diversity, and environmental health of the Refuge System;
 recognize that wildlife-dependent recreation activities including hunting, fishing, wildlife
observation, wildlife photography, and environmental education and interpretation are
legitimate and priority public uses; and
 retain the authority of refuge managers to determine compatible public uses.
Draft Comprehensive Conservation Plan 3
The following are just a few examples of the Service’s national network of conservation lands.
Pelican Island National Wildlife Refuge, the first refuge, was established in 1903 for the protection of
colonial nesting birds in Florida, such as the snowy egret and the brown pelican. Western refuges
were established for American bison (1906), elk (1912), prong-horned antelope (1931), and desert
bighorn sheep (1936) after overhunting, competition with cattle, and natural disasters decimated the
once-abundant herds. The drought conditions of the Dust Bowl during the 1930s severely depleted
breeding populations of ducks and geese. Refuges established during the Depression focused on
protecting waterfowl production areas such as the prairie wetlands in America’s heartland. The
emphasis on waterfowl continues today but also includes protection of wintering habitat in response
to a dramatic loss of bottomland hardwoods. By 1973, the Service had begun to focus on
establishing refuges for endangered species.
Recreational visits to national wildlife refuges generate substantial economic activity. In
fiscal year 2006, 34.8 million people visited refuges in the lower 48 states for recreation.
Their spending generated almost $1.7 billion of sales in regional economies. As this
spending flowed through the economy, nearly 27,000 people were employed and $542.8
million in employment income was generated.
About 82 percent of total expenditures are generated by nonconsumptive activities on refuges.
Fishing accounted for 12 percent and hunting 6 percent. Local residents accounted for 13 percent
of expenditures, while visitors coming from outside the local area accounted for 87 percent. In
addition, refuge recreational spending generates about $185.3 million in tax revenues at the
local, county, state, and federal levels.
Surveys show refuge visitors would have been willing to pay more for their visit than it actually
costs them. The difference between what they were willing to pay and what they actually paid is
their net economic value or consumer surplus. Visitors enjoyed a consumer surplus of nearly
$860 million in 2006. Over $664 million of this amount (77 percent of total net economic value)
accrued to nonconsumptive visitors.
The wildlife and habitat vision for national wildlife refuges stresses that wildlife comes first; that
ecosystems, biodiversity, and wilderness are vital concepts in refuge management; that refuges
must be healthy and growth must be strategic; and that the Refuge System serves as a model
for habitat management with broad participation from others.
The National Wildlife Refuge System Improvement Act of 1997 stipulates that comprehensive
conservation plans be prepared in consultation with adjoining federal, state, and private
landowners and that the Service develop and implement a process to ensure an opportunity for
active public involvement in the preparation and revision (every 15 years) of the plans.
All lands of the Refuge System will be managed in accordance with an approved
comprehensive conservation plan that will guide management decisions and set forth strategies
for achieving refuge unit purposes. The plan will be consistent with sound resource
management principles, practices, and legal mandates, including Service compatibility
standards and other Service policies, guidelines, and planning documents (602 FW 1.1).
4 Felsenthal and Overflow National Wildlife Refuges
LEGAL AND POLICY CONTEXT
Legal Mandates, Administrative and Policy Guidelines, and Other Special Considerations
Administration of national wildlife refuges is guided by the mission and goals of the National
Wildlife Refuge System, congressional legislation, presidential executive orders, and
international treaties. Policies for management options of refuges are further refined by
administrative guidelines established by the Secretary of the Interior and by policy guidelines
established by the Director of the Fish and Wildlife Service. A number of legal treaties and laws
relevant to the administration of the National Wildlife Refuge System and management of the
Felsenthal and Overflow national wildlife refuges are summarized in Appendix C.
Treaties, laws, administrative guidelines, and policy guidelines assist the refuge manager in making
decisions pertaining to soil, water, air, flora, fauna, and other natural resources; historical and
cultural resources; research and recreation on refuge lands; and provide a framework for
cooperation between the Felsenthal and Overflow national wildlife refuges and other partners, such
as the Arkansas Game and Fish Commission (AGFC), private landowners, etc.
Lands within the National Wildlife Refuge System are closed to public use unless specifically
and legally opened. No refuge use may be allowed unless it is determined to be compatible. A
compatible use is a use that, in the sound professional judgment of the refuge manager, will not
materially interfere with or detract from the fulfillment of the mission of the Refuge System or the
purposes of the refuge. All programs and uses must be evaluated based on mandates set forth
in the National Wildlife Refuge System Improvement Act. Those mandates are to:
 contribute to ecosystem goals, as well as refuge purposes and goals;
 conserve, manage, and restore fish, wildlife, and plant resources and their habitats;
 monitor the trends of fish, wildlife, and plants;
 manage and ensure appropriate visitor uses as those uses benefit the conservation of
fish and wildlife resources and contribute to the enjoyment of the public; and
 ensure that visitor activities are compatible with refuge purposes.
The Improvement Act further identifies six priority wildlife-dependent recreational uses. These
uses are hunting, fishing, wildlife observation, wildlife photography, and environmental
education and interpretation. As priority public uses of the Refuge System, they receive priority
consideration over other public uses in planning and management.
Biological Integrity, Diversity, and Environmental Health Policy
The Improvement Act directs the Service to ensure that the biological integrity, diversity, and
environmental health of the Refuge System are maintained for the benefit of present and future
generations of Americans. The policy is an additional directive for refuge managers to follow
while achieving refuge purpose(s) and the Refuge System mission. It provides for the
consideration and protection of the broad spectrum of fish, wildlife, and habitat resources found
on refuges and associated ecosystems. When evaluating the appropriate management
direction for refuges, refuge managers will use sound professional judgment to determine their
refuges’ contribution to biological integrity, diversity, and environmental health at multiple
landscape scales. Sound professional judgment incorporates field experience, knowledge of
refuge resources, the refuge’s role within an ecosystem, applicable laws, and best available
science, including consultation with others both inside and outside the Service.
Draft Comprehensive Conservation Plan 5
NATIONAL AND INTERNATIONAL CONSERVATION PLANS AND INITIATIVES
Multiple partnerships have been developed among government and private entities to address
the environmental problems affecting regions. A large amount of conservation and protection
information defines the role of the refuge at the local, national, international, and ecosystem
levels. Conservation initiatives include broad-scale planning and cooperation between affected
parties to address declining trends of natural, physical, social, and economic environments.
The conservation guidance described below, along with issues, problems, and trends, was
reviewed and integrated where appropriate into this draft comprehensive conservation plan.
This draft plan supports, among others, the North American Bird Conservation Initiative, North
American Waterfowl Management Plan, Partners in Flight Plan, U.S. Shorebird Conservation
Plan, and Northern American Waterbird Conservation Plan.
North American Bird Conservation Initiative. Started in 1999, the North American Bird
Conservation Initiative is a coalition of government agencies, private organizations, academic
institutions, and private industry leaders in the United States, Canada, and Mexico working to
ensure the long-term health of North America's native bird populations by fostering an
integrated approach to bird conservation to benefit all birds in all habitats. The four international
and national bird initiatives include the North American Waterfowl Management Plan, Partners
in Flight, Waterbird Conservation for the Americas, and the U.S. Shorebird Conservation Plan.
North American Waterfowl Management Plan. The North American Waterfowl Management
Plan is an international action plan to conserve migratory birds throughout the continent. The plan's
goal is to return waterfowl populations to their 1970s’ levels by conserving wetland and upland
habitats. Canada and the United States signed the plan in 1986 in reaction to critically low numbers
of waterfowl. Mexico joined in 1994, making it a truly continental effort. The plan is a partnership of
federal, provincial, state, and municipal governments, nongovernmental organizations (NGOs),
private companies, and many individuals, all working towards achieving better wetland habitat for
the benefit of migratory birds, other wetland-associated species and people. Plan projects are
international in scope, but implemented at regional levels. These projects contribute to the
protection of habitat and wildlife species across the North American landscape.
Partners in Flight Bird Conservation Plan. Managed as part of the Partners in Flight Plan,
the Mississippi Alluvial Valley and the West Gulf Coastal Plan physiographic areas represent
scientifically based land bird conservation planning efforts that ensure long-term maintenance of
healthy populations of native land birds, primarily nongame land birds. Nongame land birds
have been vastly underrepresented in conservation efforts, and many are exhibiting significant
declines. This plan is voluntary and nonregulatory, and focuses on relatively common species
in areas where conservation actions can be most effective, rather than the frequent local
emphasis on rare and peripheral populations.
U.S. Shorebird Conservation Plan. The U.S. Shorebird Conservation Plan is a
partnership effort throughout the United States to ensure that stable and self-sustaining
populations of shorebird species are restored and protected. The plan was developed by a
wide range of agencies, organizations, and shorebird experts for separate regions of the
country, and identifies conservation goals, critical habitat conservation needs, key research
needs, and proposed education and outreach programs to increase awareness of
shorebirds and the threats they face.
6 Felsenthal and Overflow National Wildlife Refuges
Northern American Waterbird Conservation Plan. This plan provides a framework for the
conservation and management of 210 species of waterbirds in 29 nations. Threats to waterbird
populations include destruction of inland and coastal wetlands; introduced predators and
invasive species; pollutants; mortality from fisheries and industries; disturbance; and conflicts
arising from abundant species. Particularly important habitats of the southeast region include
pelagic areas, marshes, forested wetlands, and barrier and sea island complexes. Fifteen
species of waterbirds are federally listed, including breeding populations of wood storks,
Mississippi sandhill cranes, whooping cranes, interior least terns, and Gulf Coast populations of
brown pelicans. A key objective of this plan is the standardization of data collection efforts to
better recommend effective conservation measures.
RELATIONSHIP TO STATE WILDLIFE AGENCY
A provision of the National Wildlife Refuge System Improvement Act of 1997, and subsequent
agency policy, is that the Service shall ensure timely and effective cooperation and collaboration
with other state fish and game agencies and tribal governments during the course of acquiring
and managing refuges. State wildlife management areas and national wildlife refuges provide
the foundation for the protection of species, and contribute to the overall health and sustainment
of fish and wildlife species in the State of Arkansas. Figure 1 displays regional conservation
areas in the vicinity of Felsenthal and Overflow NWRs.
The Arkansas Game and Fish Commission (AGFC) is responsible for the control, management,
restoration, conservation, and regulation of birds, fish, game and wildlife resources of the state.
The mission of AGFC is “… to wisely manage all the fish and wildlife resources of Arkansas
while providing maximum enjoyment for the people.” The AGFC oversees more than 280,000
acres of state-owned Natural Areas and Wildlife Management Areas, and more than 100 natural
and man-made lakes. The agency manages habitat; stocks fish; develops management plans
for important wildlife species; and fosters good stewardship through a variety of education
programs, information products, and grants for conservation activities.
The AGFC’s participation and contribution throughout this planning process will provide for
ongoing opportunities and open dialogue to improve the ecological sustainment of fish and
wildlife in the State of Arkansas. An essential part of comprehensive conservation planning is
the integration of common mission objectives where appropriate.
Draft Comprehensive Conservation Plan 7
Figure 1. Location of Felsenthal and Overflow National Wildlife Refuges and the
Oakwood Unit.
8 Felsenthal and Overflow National Wildlife Refuges
Draft Comprehensive Conservation Plan 9
II. Refuge Overview
INTRODUCTION
FELSENTHAL NATIONAL WILDLIFE REFUGE
Felsenthal National Wildlife Refuge (NWR) is located in Ashley, Bradley, and Union counties,
Arkansas, about 5 miles west of Crossett, Arkansas on U.S. Highway 82 (Figure 2). Felsenthal
NWR is one of four refuges forming an administrative complex, which also includes Pond Creek
National Wildlife Refuge to the northwest, Overflow National Wildlife Refuge to the east, and the
Oakwood Unit National Wildlife Refuge to the northeast.
Felsenthal NWR occupies a low-lying area dissected by an intricate system of rivers, creeks,
sloughs, buttonbush swamps and lakes throughout a vast bottomland hardwood forest that
gradually rises to an upland forest community. Historically, periodic flooding of the "bottoms"
(bottomland hardwoods) during winter and spring provide excellent wintering waterfowl habitat.
These wetlands, in combination with the pine and upland hardwood forest on the higher ridges,
support a wide diversity of native plants and animals, providing habitat for migrant and resident
waterfowl, marsh and water birds, and neotropical migratory birds. The refuge has the highest
density of endangered red-cockaded woodpeckers in the state and provides habitat and
protection for the threatened American alligator. The refuge also contains some of the region's
richest cultural resources with more than 200 known archeological (Native American) sites.
OVERFLOW NATIONAL WILDLIFE REFUGE
Overflow NWR is located in Ashley County, Arkansas, five miles west of Wilmot, Arkansas
(Figure 3). There is no direct highway access to the refuge, except by Highway 173. From
Highway 165 take Highway 173W, to the parking lot at the end of pavement.
The western boundary of the Overflow Refuge follows the 110-foot contour along the
Mississippi Alluvial Valley escarpment; an abrupt rise in elevation separates the Mississippi
River Delta from the Gulf Coastal Plain. Bottomland hardwood forests, agricultural fields,
scrub/shrub wetlands and beaver ponds, and upland pine-hardwood are the principal habitats
on the refuge. These habitats provide a diversity of habitat types and protection for migratory
waterfowl and other birds, including the American bald eagle.
Few species surveys have been conducted on the refuges. Although actual numbers are hard
to accurately quantify, comparisons with other similar refuges with similar habitats envisage
that the current wildlife list for Felsenthal and Overflow would contain at least 200 species of
birds, 40 species of mammals, 70 species of reptiles and amphibians, and 90 species of fish.
The species lists are provided in Appendix I, Refuge Biota.
10 Felsenthal and Overflow National Wildlife Refuges
Figure 2. Acquisition boundary of Felsenthal National Wildlife Refuge.
Draft Comprehensive Conservation Plan 11
Figure 3. Acquisition boundary of Overflow National Wildlife Refuge.
12 Felsenthal and Overflow National Wildlife Refuges
REFUGE HISTORY AND PURPOSE
HISTORY
Felsenthal National Wildlife Refuge
Established in 1975 as mitigation for the creation of the U.S. Corps of Engineers’ (USACE)
Ouachita and Black Rivers Navigation Project and Felsenthal Lock and Dam, Felsenthal
National Wildlife Refuge (NWR) is located in southeast Arkansas, approximately eight miles
west of the town of Crossett. This 65,000-acre refuge is named for the small Felsenthal
community located at its southwest corner, and contains an abundance of water resources
dominated by the Ouachita and Saline rivers and the Felsenthal Pool.
Geographically, the refuge is located in what is known as the Felsenthal Basin, an extensive
natural depression that is laced with a vast complex of sloughs, bayous and lakes (Figure 2). The
region's two major rivers, the Saline and Ouachita, flow through the refuge. These wetland areas
in combination with the refuge's diverse forest ecosystem of bottomland hardwoods, pine forests
and uplands support a wide variety of wildlife and provide excellent fishing, hunting, boating,
wildlife observation and environmental education opportunities. This low lying refuge area is
dissected by an intricate system of rivers, creeks, sloughs, buttonbush swamps and lakes spread
throughout a vast bottomland hardwood forest that gradually rises to an upland forest community.
Historically, periodic flooding of the "bottoms" during winter and spring provided excellent
wintering waterfowl habitat. These wetlands, in combination with the pine and upland hardwood
forest on the higher ridges, support a wide diversity of native plants and animals.
About 60% of the refuge (~40,000 acres) is bottomland hardwood, 25% open water (~15,000
acres), and 15% uplands (~10,000 acres). Felsenthal NWR has the world's largest greentree
reservoir consisting of the 15,000-acre Felsenthal Pool that is more than doubled to 36,000
acres during winter flooding.
Overflow National Wildlife Refuge
Overflow National Wildlife Refuge, established in 1980, encompasses 13,973 fee-title acres in
Ashley County in southeast Arkansas, about five miles west of Wilmot (Figure 3). It was
established to protect one of the remaining bottomland hardwood forests considered vital for
maintaining mallard, wood duck, and other waterfowl populations in the Mississippi Flyway. The
bottomland hardwood forest consists primarily of willow oak and overcup oak. The willow oaks
produce small acorns that are an excellent source of food for the mallards and wood ducks in
the winter. Bald cypress and tupelo gum occur along streams, channels and sloughs
throughout the refuge. This 13,000+ acre wetland complex consists of seasonally flooded
bottomland hardwood forests, impoundments, and croplands. In addition, the Oakwood Unit (an
area of 2,263 acres in Desha County transferred from the Farmers Home Administration in
1990) is administered by Overflow NWR. The Oakwood Unit is currently closed to the public
and is very passively managed. Where warranted, appropriate information relating to the
Oakwood Unit will be included in this CCP.
About 60% of Overflow NWR is bottomland hardwoods (~8,650 acres), about 15% reforested
(~2,020 acres), about 15% wetlands and beaver ponds (~1,500 acres), with the remaining
acreage in agriculture (~800 acres) and upland pine-hardwoods (200-300 acres). During the
winter, a 4,000-acre greentree reservoir is created when the bottomland hardwood forests are
Draft Comprehensive Conservation Plan 13
allowed to flood. About 60% of the acreage of the Oakwood Unit is reforested, about 30% is in
waterfowl impoundments, and about 10% is bottomland hardwoods.
PURPOSE
Felsenthal National Wildlife Refuge
The purpose and establishing authorities of Felsenthal NWR are:
 16 U.S.C. § 664 (Fish and Wildlife Coordination Act)
"... shall be administered by him [Secretary of the Interior] directly or in accordance with
cooperative agreements ... and in accordance with such rules and regulations for the
conservation, maintenance, and management of wildlife, resources thereof, and its
habitat thereon ..."
 16 U.S.C. § 460k-1
"... suitable for incidental fish and wildlife-oriented recreational development; the
protection of natural resources; and the conservation of endangered species or
threatened species ..."
 16 U.S.C. § 460k-2 (Refuge Recreation Act (16 U.S.C. § 460k-460k-4), as amended)
"... the Secretary ... may accept and use ... real ... property. Such acceptance may be
accomplished under the terms and conditions of restrictive covenants imposed by
donors ..."
Felsenthal NWR is operated under the following management objectives:
 Provide habitat for migratory waterfowl and other birds;
 Provide habitat and protection for endangered species such as the red-cockaded
woodpecker, and the threatened American alligator and the protected bald eagle;
 Provide recreation and environmental education for the public; and
 Protect cultural resources.
Overflow National Wildlife Refuge
The purpose and establishing authorities of Overflow NWR are:
 16 U.S.C. § 715d (Migratory Bird Conservation Act)
“…for use as an inviolate sanctuary, or for any other management purpose, for migratory
birds.”
 16 U.S.C. § 460k-1
“…suitable for incidental fish and wildlife oriented recreational development; the
protection of natural resources; and the conservation of endangered species or
threatened species…”
 16 U.S.C. § 460k-2 (Refuge Recreation Act (16 U.S.C. § 460k-460k-4), as amended)
“…the Secretary …may accept and use…real…property. Such acceptance may be
accomplished under the terms and conditions of restrictive covenants imposed by
donors…”
14 Felsenthal and Overflow National Wildlife Refuges
 16 U.S.C. § 668dd(a)(2) (National Wildlife Refuge System Administration Act)
“…conservation, management, and …restoration of the fish, wildlife, and plant resources
and their habitats…for the benefit of present and future generations of Americans…”
On August 8, 1990, the Service received fee title to the 2,263-acre Oakwood Unit from the
Farmers Home Administration (FmHA). This transaction represents the largest contiguous tract
of land transferred to the Service by the FmHA. There was a long history of court battles and
legal maneuvering by the previous landowner and FmHA over this controversial FmHA
inventory property. However, the transfer went relatively smoothly with the Service completing
habitat restoration in 1996 (Figure 4).
Overflow NWR is operated under the following management objectives:
 Provide a diversity of habitat types for migratory waterfowl and other birds.
 Provide habitat and protection for endangered and threatened.
 Provide opportunities for environmental and ecological research.
 Provide a variety of recreational opportunities consistent with primary wildlife objectives.
 Expand the public’s understanding of and appreciation for the environment with special
emphasis on natural resources.
SPECIAL DESIGNATIONS
Felsenthal and Overflow NWRs do not contain any lands under special designation by the
federal government, such as federally designated wilderness areas, wild and scenic rivers,
demonstration areas, or research natural areas. However, the General Accounting Office’s
Report on Oil and Gas on Wildlife Refuges (GAO-03-517) lists 60 inactive wells and pipelines
on Felsenthal NWR and two inactive wells and pipelines on Overflow NWR.
The Saline River, from its confluence with the Ouachita River in Felsenthal NWR, upstream to
the Grant/Saline County line in central Arkansas (a distance of 157 miles) has been designated
as one of Arkansas' Natural and Scenic Rivers. These rivers are classified as natural, scenic,
or pastoral. The criteria involve the stream’s length, adjacent forest cover, biological
characteristics, water quality, present use, and accessibility. A river or river segment listed in
the system is protected from any permanent dam or structure that would impound waters or
any channelization or realignment of the principal channel of the stream. Similarly, the
Nationwide Rivers Inventory (NRI) also lists the Saline River from its confluence with the
Ouachita River, in Felsenthal NWR, upstream to its confluence with Alum Fork and North Fork
(a 179-mile segment) as having outstandingly remarkable values of scenery, recreation, fish,
wildlife and history. Immediately below Felsenthal NWR, the Ouachita River flows into
Louisiana, where it is a state-designated scenic stream.
Both Felsenthal and Overflow NWRs are recognized as important bird areas (IBAs) by Audubon
Arkansas.
Draft Comprehensive Conservation Plan 15
Figure 4. Acquisition boundary of Oakwood Unit of Overflow National Wildlife Refuge.
16 Felsenthal and Overflow National Wildlife Refuges
ECOSYSTEM CONTEXT
LOWER MISSISSIPPI RIVER ECOSYSTEM
An ecosystem is a geographical area that includes and interconnects all the living (biotic)
organisms, their physical (abiotic) surroundings, and the natural cycles that sustain them. All of
these elements are interconnected. Managing any one resource affects the others in that
ecosystem. Ecosystems can be small (a single stand of aspen) or large (an entire watershed
including hundreds of forest stands across many different ownerships).
The Lower Mississippi River Ecosystem includes the alluvial plain of the Mississippi River
downstream of its confluence with the Ohio River and the delta plain and associated marshes and
swamps created by the meanderings of the Mississippi River and its tributaries (FWS 2002). The
drainage basins and tributaries of the Ouachita River, which includes Felsenthal and Overflow
NWR's are part of the West Guld Coastal Plain (Felsenthal NWR) and the Mississippi Alluvial Valley
(Overflow NWR) sections of the Lower Mississippi River Ecosystem (Figure 5).
The refuges characterized by bottomland hardwoods and wetlands, are managed for
conservation, enhancement, and restoration of bottomland hardwoods; moist soil management;
endangered species protection; environmental education; and compatible wildlife-dependent
recreation in the Lower Mississippi River Ecosystem. The ecosystem guides Fish and Wildlife
Service efforts to enhance, restore, and conserve the natural functional processes and habitat
types, while maintaining economic productivity and recreational opportunities.
The ecosystem serves as a primary wintering habitat for mid-continent waterfowl populations,
as well as breeding and migration habitat for migratory songbirds. The expansive floodplain
forests of the past are now fragmented bottomland hardwood patches due to conversion from
agriculture and flood control projects.
The West Gulf Coastal Plain and Felsenthal National Wildlife Refuge
The West Gulf Coastal Plain is composed of rolling plains that are broken by nearly flat fluvial
terraces, bottomlands, sandy low hills, and low cuestas; its terrain is unlike the much more
rugged Ouachita Mountains to the north or the flatter, less dissected Mississippi Alluvial Valley
to the east. Uplands are underlain by poorly-consolidated, Tertiary- through Cretaceous-age,
coastal plain deposits and marginal marine sediments (laid down as the Gulf of Mexico opened
and North America’s southern continental margin subsided). Bottomlands and terraces are
veneered with Quaternary alluvium or windblown silt deposits (loess). The lithologic mosaic is
distinct from the Paleozoic rocks of the Ouachita Mountains and the strictly Quaternary deposits
of the Mississippi Alluvial Valley. Potential natural vegetation is oak–hickory–pine forest on
uplands and southern floodplain forest on bottomlands. Today, more than 75% of the ecoregion
remains wooded. Extensive commercial loblolly pine–shortleaf pine plantations occur. Lumber
and pulpwood production, livestock grazing, and crawfish farming are also major land uses.
Cropland usually dominates the drained bottomlands. Fish communities typically have a limited
proportion of sensitive species; sunfishes are dominant, and darters and minnows are common.
Draft Comprehensive Conservation Plan 17
Figure 5. Lower Mississippi River Ecosystem.
18 Felsenthal and Overflow National Wildlife Refuges
In the immediate vicinity of Felsenthal NWR, the ecosystem is characterized by floodplains and
low terraces. It is nearly level, veneered by Holocene alluvium, and contains natural levees,
swales, oxbow lakes, and meander scars. Longitudinal channel gradients are low and large
parts are frequently flooded. Forested wetlands are characteristic, but pastureland also occurs.
Potential natural vegetation is southern floodplain forest as in the Mississippi Alluvial Valley (see
below), and cropland is less common.
The Mississippi Alluvial Valley and Overflow National Wildlife Refuge
The Mississippi Alluvial Valley extends along the Mississippi River from the confluence of the
Ohio and Mississippi rivers southward to the Gulf of Mexico. The Mississippi Alluvial Valley
Plain is a broad, nearly level, agriculturally-dominated alluvial plain. It is veneered by
Quaternary alluvium, loess, glacial outwash, and lacustrine deposits. River terraces, swales,
and levees provide limited relief, but overall, the Mississippi Alluvial Valley is flatter than the
neighboring South Central Plains ecoregions in Arkansas. Nearly flat, clayey, poorly-drained
soils are widespread and characteristic. Streams and rivers have very low gradients and fine-grained
substrates. Many reaches have ill-defined stream channels. The Mississippi Alluvial
Valley provides important habitat for fish and wildlife, and includes the largest continuous
system of wetlands in North America. It is also a major bird migration corridor used in fall and
spring migrations. Potential natural vegetation is largely southern floodplain forest and is unlike
the oak–hickory and oak–hickory–pine forests that dominate uplands to the west. Loblolly pine,
so common in the South Central Plains, is not native to most forests in the Arkansas portion of
the Mississippi Alluvial Valley. The Mississippi Alluvial Valley has been widely cleared and
drained for cultivation; this widespread loss or degradation of forest and wetland habitat has
impacted wildlife and reduced bird populations. Fish communities in least altered streams
typically have an insignificant proportion of sensitive species; sunfishes are dominant followed
by minnows. Man-made flood control levees, in effect, separate the river and its adjoining
habitat from the remainder of its natural hydrologic system; in so doing, they interfere with
sediment transfer and have reduced available habitat for many species. Earthquakes in the
early nineteenth century offset river courses in the Mississippi Alluvial Valley. Small to medium
size earthquakes still occur frequently; their shocks are magnified by the alluvial valley’s
unconsolidated deposits, creating regional land management issues.
In the immediate vicinity of Overflow NWR, the ecosystem is a flat to nearly flat floodplain
containing the meander belts of the present and past courses of the lower Arkansas and
Ouachita Rivers. Point bars, natural levees, swales, and abandoned channels, marked by
meander scars and oxbow lakes, are common and characteristic. Soils on natural levees are
relatively coarse-textured, well-drained, and higher than those on levee back slopes and point
bars; they grade to heavy, poorly-drained clays in abandoned channels and swales. The area
contains small streams flowing in abandoned courses of the Arkansas River. These small
streams are usually underfit relative to the older channels, higher than the adjacent
Arkansas/Ouachita River Backswamps (see below), and have small watersheds. Bayou
Bartholomew inhabits the longest section of abandoned channels. It flows against the edge of
and receives drainage from the West Gulf Coastal Plain which lies to the west. Habitat diversity
is sufficient for Bayou Bartholomew to be one of the most species-rich streams in North
America. Within an abandoned course, bald cypress and water tupelo often grow in the modern
stream channel adjacent to a strip of wet bottomland hardwood forest dominated by overcup
oak and water hickory. Cropland and pastureland are widespread; soybeans, rice, and wheat
are the main crops. The flats, swales, and natural levees of the Arkansas/Ouachita River
Backswamps include the slackwater areas, where water often collects into marshes, swamps,
oxbow lakes, ponds, and sloughs. This area is widely veneered with natural levee deposits.
Draft Comprehensive Conservation Plan 19
Soils derived from these natural levee deposits are coarser and are not as poorly drained as the
clayey soils of the Northern Backswamps. As a result, willow oak and water oak are native
instead of species adapted to wetter overflow conditions. Drainage canals and ditches are
common. This artificial drainage, together with the sandy veneer of natural levee deposits, help
explain why the area is easily and widely farmed. Rice, cotton, and soybeans are important
crops but forests and forested wetlands also occur.
Both Felsenthal and Overflow NWRs are located in the U.S. Fish and Wildlife Service's Lower
Mississippi River Watershed Ecosystem Unit (Figure 6). The Service’s ecosystem approach is
comprehensive. It is based on all of the biological resources within a watershed and it
considers the economic health of communities within that watershed. A watershed is the total
land area from which water drains into a single stream, lake, or ocean. The U.S. Fish and
Wildlife Service’s Lower Mississippi Ecosystem Team has eight goals, as follows:
Resource Goals. The first five goals address the primary living natural resources and their
habitats of concern to the Fish and Wildlife Service in the Lower Mississippi River Ecosystem.
1. Conserve, enhance, protect, and monitor migratory bird populations and their habitats in the
Lower Mississippi River Ecosystem.
2. Protect, restore, and manage the wetlands of the Lower Mississippi River Ecosystem.
3. Protect and/or restore imperiled habitats and viable populations of all endangered,
threatened, and candidate species and species of concern in the Lower Mississippi River
Ecosystem.
4. Protect, restore, and manage the fisheries and other aquatic resources historically
associated with the wetlands and waters of the Lower Mississippi River Ecosystem.
5. Restore, manage, and protect national wildlife refuges and national fish hatcheries.
Support Goals. The following goals support the accomplishment of all five goals listed above:
wetlands, migratory birds, endangered species, fisheries, and Service lands. The support goals
are essential to the overall accomplishment of the Ecosystem mission, but do not fit entirely
within any one of the five resource goals.
6. Increase public awareness and support for Lower Mississippi River Ecosystem resources
and their management.
7. Enforce natural resource laws.
8. Protect, restore, and enhance water and air quality throughout the Lower Mississippi River
Ecosystem.
20 Felsenthal and Overflow National Wildlife Refuges
Figure 6. USFWS-designated ecosystems in the U.S., showing the Lower Mississippi
River Watershed Ecosystem (#27).
Draft Comprehensive Conservation Plan 21
REGIONAL CONSERVATION PLANS AND INITIATIVES
Comprehensive conservation plans (CCPs) and environmental assessments are being prepared
for the ten U.S. Fish and Wildlife refuges in the state of Arkansas. The CCPs will provide the
Service’s refuge managers with a 15-year strategy and broad direction to conserve fish and
wildlife and their habitats; to achieve refuge purposes; and to contribute toward the mission of
the National Wildlife Refuge System. In addition, the plans identify wildlife-dependent
opportunities available to the public, including opportunities for hunting, fishing, wildlife
observation, wildlife photography, and environmental education and interpretation. The Pond
Creek NWR CCP was completed in 2000 and CCPs for the remaining nine refuges (Logan
Cave, Holla Bend, Cache River, Bald Knob, Big Lake, Wapanocca, Felsenthal, Overflow, and
White River) are currently in various stages of preparation.
Many regional conservation plans and initiatives are derivatives of national plans (please refer
to Chapter I, Background, National and International Conservation Plans and Initiatives). These
regional plans are developed by a variety of cooperating regional organizations and agencies
and are being planned and implemented in the southeastern U.S. The more notable which are
compatible with the mission and purpose of Felsenthal and Overflow NWRs are:
Arkansas's Comprehensive Wildlife Conservation Strategy (CWCS). Supported by the
State Wildlife Grants (SWG) Program, Arkansas's CWCS (also known as the Wildlife Action
Plan) identifies the challenges facing Arkansas's diverse wildlife species and devises strategies
to conserve those "species with the greatest conservation need," and their habitats. The CWCS
is a guide to conserving the species of fish and wildlife that have immediate conservation needs
or are key indicators of the diversity and health of the state’s wildlife. The CWCS emphasizes a
cooperative, proactive approach to conservation, inviting local governments, businesses and
conservation-minded organizations and individuals to join in the task of maintaining the fish and
wildlife resources. Arkansas's Wildlife Action Plan addresses the conservation needs of 369
species of greatest conservation need in the context of 45 terrestrial habitats and 18 aquatic
habitats in the seven ecoregions in the state.
The Red-Cockaded Woodpecker (RCW) Recovery Plan. The ultimate recovery goal is red-cockaded
woodpecker (Picoides borealis) viability. Once this goal is met the size, number, and
distribution of populations will be sufficient to counteract threats of demographic, environmental,
genetic, and catastrophic stochastic events, thereby maintaining long-term viability for the
species as defined by current understanding of these processes. Also, referred to as the RCW
Safe Harbor program, it seeks private cooperators and private lands to facilitate the recovery
efforts of the RCW. Regions and habitat types currently occupied by the species will be
documented, given habitat limitations.
Southeast Aquatic Resources Partnership (SARP). The Southeast Aquatic Resources
Partnership includes fish and wildlife agencies from 14 southeastern states; the Gulf and
Atlantic States Marine Fisheries Commissions; the Gulf of Mexico and South Atlantic
Fishery Management Councils; the U.S. Fish and Wildlife Service; and the Fisheries
Division of the National Oceanic and Atmospheric Administration (NOAA). The SARP
focuses on six key issue areas: Aquatic Habitat Conservation; Public Use; Imperiled Fish
and Aquatic Species Recovery; Fishery Mitigation; Interjurisdictional Fisheries; and Aquatic
Nuisance Species (ANS). These partnering entities work together for the conservation and
management of aquatic resources in the Southeast.
22 Felsenthal and Overflow National Wildlife Refuges
The Nature Conservancy's (TNC) Upper West Gulf Coastal Plain Ecoregional Plan. This
plan represents the Nature Conservancy's ecoregional conservation planning effort for the
Upper West Gulf Coastal Plain. The plan provides a portfolio of conservation areas, including
priority or action areas, the data compiled and created during this planning effort, methodology,
the data gaps identified, and strategies for plan implementation. It is intended that conservation
planners, site-based conservation staff, and TNC partners use this plan to effectively manage
the biodiversity of the ecoregion. Successful use requires a commitment of cooperation,
resources and time, as well as the sharing of responsibility and effort.
Partners for Fish and Wildlife. The Service’s Partners for Fish and Wildlife Program
(Partners) is working with landowners to restore, enhance, and protect fish and wildlife
habitat on private lands. Through alliances with organizations and individuals, the Partners
program is a voluntary partnership whose focus is to restore vegetation and hydrology to
historic conditions on private lands.
Northern Bobwhite Conservation Initiative (NCBI). The NBCI's charge is to develop a
quantitative habitat-oriented plan to restore bobwhites to the density they enjoyed during the
baseline year 1980.
Arkansas Department of Environmental Quality (ADEQ) Strategic Plan (2004-2014). The
ten-year strategic plan outlines ADEQ's guiding principles, objectives, and strategies for
improving the environment in Arkansas. This strategic plan is built around four environmental
goals: (a) Air; (b) Water; (c) Land; and (d) Environmental Management. In accomplishing this
plan ADEQ partners with the U.S. Environmental Protection Agency, the Arkansas Pollution
Control and Ecology Commission, the Arkansas Natural Resources Commission, the Arkansas
Department of Health, the Arkansas Forestry Commission, the Arkansas Geological
Commission, the Arkansas Game and Fish Commission, the Arkansas Oil and Gas
Commission, and many others.
Mississippi Embayment Regional Aquifer Study. As part of the U.S. Geologic Survey’s
(USGS) Groundwater Resources Program, a groundwater flow model of the northern
Mississippi embayment will be developed using data and knowledge gained from the Gulf
Coast Regional Aquifer System Analysis (GCRASA) studies and other more recently
completed USGS models to aid in answering questions about groundwater availability. The
proposed study area covers portions of seven states, including Arkansas, Louisiana,
Mississippi, Tennessee, Alabama, Missouri, and Kentucky. The program’s rectangular
model grid will cover almost 158,000 square miles, while the active portion to be simulated
will cover approximately 70,000 square miles.
Felsenthal National Wildlife Refuge Greentree Reservoir Study. This initiative consists of a
study of the survival and growth of trees impacted by greentree reservoir management and the
development of a water management plan that minimizes the impacts to the wetland community
and provides high quality waterfowl habitat for the long term.
ECOLOGICAL THREATS AND PROBLEMS
FELSENTHAL NATIONAL WILDLIFE REFUGE
Nuisance aquatic vegetation around the Felsenthal NWR region includes fanwort, hydrilla,
American lotus, water hyacinth, and giant salvinia. This vegetation covers up to 75% of the
water surface by mid-summer. An aquatic vegetation management plan needs to be
Draft Comprehensive Conservation Plan 23
developed and implemented. The ramifications of the use of aquatic herbicides and/or the
stocking of diploid grass carp to control vegetation need to be carefully considered. The decay
of aquatic vegetation in late summer/fall causes oxygen depletion and results in fish die-offs.
A proposed point source wastewater discharge to the Ouachita River 22 river miles upstream of
Felsenthal NWR threatens downstream water quality and water use on the refuge. The
proposed wastewater outfall would contain the combined effluent from four entities: El Dorado
Water Utilities, El Dorado Chemical Company, Great Lakes Chemical Corporation (now
Chemtura Chemical Corporation), and Lion Oil Company. The effluent would likely have large
amounts and high levels of ammonia, nutrients, and dissolved solids. The total quantity and
quality of effluent to be discharged from this proposed collective point source has not been
disclosed, but individually these industrial sources have a questionable history of water pollution
problems and NPDES permit violations.
Nuisance wildlife species are also an issue on the refuge. Beavers and feral hogs have few
natural predators, a prolific reproductive rate, and thousands of acres of prime habitat. Because
beavers have the potential to destroy or alter thousands of acres of valuable bottomland
hardwood habitat, beaver control is a management priority and a management policy needs to
be developed and implemented.
Mercury contamination is currently an environmental concern on the lower Ouachita (and Saline
Rivers), including Felsenthal NWR. Human health and fish consumption advisories for mercury
have been issued by the State of Arkansas for pregnant women, women who may become
pregnant, women who are breast-feeding, and children under the age of seven.
Bioaccumulation of methyl mercury in the food chain has resulted in high mercury tissue levels
in fish, birds, and mammals that are expected to cause adverse impacts to fish and wildlife and
have raised concerns over fish and duck consumption. Commercial fishing for buffalo and
channel catfish was reopened by the state in 1999 after having been closed for eight years due
to mercury contamination, when sampling analyses revealed mercury levels for buffalo and
channel catfish had fallen below the Food and Drug Administration's advisory level.
The numbers of exotic fish species are on the rise and several Asian carp species have
successfully invaded and established populations within nearby waters. Silver carp and
bighead carp are invasive species known to populate rivers of Arkansas and Louisiana,
threatening the biological integrity of native aquatic habitats and having the potential to inhabit
and establish populations in Felsenthal and Overflow NWRs.
The overall health of the forest within the greentree reservoir (GTR) is deteriorating because of
the current GTR water level management regime. Specifically, the two most desired species of
oaks—willow oak and nuttall oak—are decreasing in numbers, and more water-tolerant species
such as overcup oak and water hickory are increasing. Additionally, recruitment of new trees
into the forest system is not occurring due to high water levels drowning out the seedlings. This
constitutes the loss of the most important mast-producing tree species within the GTR. The
forest composition is shifting to more water-tolerant species such as overcup oak and water
hickory, which have little value for waterfowl. Unless flooding is curtailed during some years,
the mass-producing overstory trees will eventually be lost, waterfowl habitat will decrease, and
waterfowl hunting opportunities will be lessened. Water level management procedures,
including pool elevations/water depth and timing of flooding for Felsenthal GTR, need to be
developed, finalized and formally implemented.
24 Felsenthal and Overflow National Wildlife Refuges
In recent years, wintering waterfowl (ducks) numbers have been severely depressed, compared
to long-term averages. Similar conditions exist throughout most of east and south Arkansas
with bird numbers far below historic levels. The cause of this rapid decline is an important
ecological challenge which needs to be investigated and ameliorated.
Oil spills on the refuge, caused by deteriorated lines and storage tanks located at old, existing
oil well sites, need to be eliminated. Increased management emphasis and maintenance of old
and deteriorating oil equipment and facilities are needed to ensure this threat is addressed. An
example of this is found in the Felsenthal National Wildlife Refuge Annual Narrative, 2005, as
follows: "EMCO, owner and operator of the Charivari Creek Oil Field on the refuge,
experienced two separate oil spills during the year (also had two during 2004). In both
instances, transport lines from the wellhead to the storage tank batteries ruptured and
discharged around one barrel of crude. Remediation was performed as directed by ADEQ.
Given the deteriorated condition of virtually all transport lines and the tank battery, similar
mishaps are sure to occur. Under the conditions of the SUP, the refuge has received monetary
damages from EMCO in times past for oil and/or salt water spills. Ecological Services
contaminant specialists and refuge staff are aggressively attempting to get EPA involved and
continue to request a full-scale inspection of these facilities."
OVERFLOW NATIONAL WILDLIFE REFUGE
There is practically a complete loss of wetlands and associated vegetation near and adjacent to
the Overflow Refuge. Bayou Bartholomew is very close to Overflow Creek in certain areas, but
its banks consist of the same alluvial sandy loam characteristic of the banks of the Arkansas
River which once occupied the bayou’s current channel. This is the favored soil for agriculture;
consequently, much of it has been farmed for over 100 years resulting in a loss of vegetative
connectivity between the two streams.
The effects of agriculture and timber harvesting practices and hydrologic modifications (ditches,
levees, canals, etc.) of surface streams in the coastal plain on the west side have created
severe siltation problems. In Flat Slough Ditch (a ditch dug in the 1960s to provide agricultural
drainage), water quality is severely impaired due to the volume of runoff associated with
agriculture and the affects of Overflow Creek. In addition, impoundment of irrigation runoff by
beavers along with siltation has resulted in a significant loss of bottomland hardwoods and
prolific weed growth in the Overflow Creek channel. The beaver dams and vegetation have
brought drainage to a standstill in several locations.
Feral hogs interact with native species by intensively competing for food, causing major crop
damage, and road/levee damage. Hog populations have fluctuated widely over the years
primarily in response to acorn availability. However, in recent years, hog hunters have released
hogs in areas throughout the southeast to increase hunting opportunities for this species. There
is also a free-running hog problem approximately one mile east of the refuge across Bayou
Bartholomew. The hogs are highly sought after by hunters and many are caught by farmers
who trap adjacent to the refuge in an effort to minimize crop damage. An estimated 500 hogs
have been removed by these methods in the last year, but there are still at the very least that
many left. They are very prolific, with a sow being capable of having 20 young per year with
high survival rates. The young are reproductively mature at an age of six months.
Draft Comprehensive Conservation Plan 25
Population control policies and practices need to be developed and implemented to manage
overpopulation of raccoons, fox, bobcat, opossum, skunk (and other furbearing mammals).
Several species are above carrying capacity and have reached nuisance levels. Canine
distemper is common among raccoons when populations are extremely high.
At the present time there is no active Forest Habitat Management Plan in place for Overflow
NWR. A management plan needs to be developed and implemented that specifically
addresses the following critical issues:
 Aforestation on newly acquired and on higher elevation lands;
 Pine tree intrusion (from windblown seeds growing on the coastal plain) that have been
displacing hardwood habitat (much of the pine is of merchantable size for pulpwood);
 Control of beaver populations which have flooded bottomland hardwoods and threaten
hardwood forest survival; and
 Policies related to future logging operations and salvage cutting.
The water quality where channelization/dredging have taken place is very turbid and
contaminated with residuals of organochlorines and current use pesticides. These chemicals
were identified in 2001 as result of a study entitled “Chemical Contamination at National Wildlife
Refuges in the Lower Mississippi River Ecosystem.” Numerous fish of all species were found to
harbor various levels of farm chemicals and other potentially toxic substances when a Level II
Contaminant Survey was conducted during the initial acquisition of the refuge. Therefore, a
fishing program has never been initiated and fishing is not allowed on Overflow NWR.
OTHER THREATS AND PROBLEMS
Opportunities for environmental education, interpretation, outreach, and visitor services need to
be increased. Careful planning (that includes goals, strategies, and evaluation criteria) WILL
provide the visiting public with opportunities to enjoy and appreciate the two refuges’ fish,
wildlife, plants, and other resources. An up-to-date Visitor Services Plan that addresses an
environmental education and interpretation program; visitor center maintenance and operation;
visitor facility construction projects; volunteer programs; attractive kiosks and signage; use of
cutting-edge media to more regionally (not just locally) inform the public of hunting, fishing, and
observation/photography opportunities, etc. is critically needed for both the Felsenthal and
Overflow NWRs.
Wildfires are a constant threat to the reforested areas. In the last 15 years, three have been
documented; two at the Oakwood Unit and one at Overflow.
Issues at the Oakwood Unit include chronic poaching on the edges of the unit; beaver activities
interfering with water management by damning waterways, blocking water control structures
and causing flooding in undesired locations; groundwater with high concentrations of chloride
(3,000 ppm); and extreme soil, bank, and levee erosion at the southeast corner of the unit.
All together, these growing pressures raise concerns for the survival of plants and animals that
are dependent on the varied natural landscapes of the refuges. Changes in natural habitats
may potentially render these altered habitats unsuitable for wildlife.
26 Felsenthal and Overflow National Wildlife Refuges
PHYSICAL RESOURCES
CLIMATE
The climate of southeast Arkansas can be characterized as humid and subtropical. Monthly mean
temperatures are generally around 80o Fahrenheit (F) in the summer. Winter monthly mean
temperatures are around 45o F. Winters are short and generally quite mild, but cold periods (below
0o F) of brief duration have occurred. Summers are hot and very humid, with daily highs frequently
exceeding 100o F in July and August. In southeast Arkansas, the growing season is very long (over
230 days), encouraging vegetative growth, especially unwanted weeds, in mid to late summer. The
southern and eastern areas of Arkansas tend to have extended warm and humid periods; with
higher humidity and more cloudiness than the rest of the state.
Annual precipitation totals range roughly from 45 to 55 inches across the state, with totals increasing
from northwest to southeast (due to the greater availability of Gulf of Mexico moisture in the
southeast). Average annual rainfall in the Felsenthal-Overflow NWR area is between about 54 and
58 inches. Rainfall is generally abundant throughout the year. The driest months tend to be August
and September, although these totals for these two months still average more than three inches
(Tables 1 and 2). The number of days with measurable precipitation averages about 100 per year.
Most of the precipitation falls as rain. Heavy local storms that produce totals of five to ten inches
over extensive areas are not uncommon. Snowfall does occur, but is generally light and remains on
the ground only briefly. Snowfall accumulation averages only about one and a half inches a year in
southern Arkansas. Tornadoes are most frequent from March through May, with about 15 to 20
reported each year. The temperature and precipitation data summarized in Tables 1 and 2 were
collected in Crossett and El Dorado from 1971 through 2000.
This annual weather cycle was a driving force in development of the climax forest types until around
1980 when a severe drought forced farmers to irrigate crops to ensure their survival. Afterwards,
summer irrigation became a standard agricultural method to ensure crop survival. The surplus
irrigation runoff occurring throughout the summer created flows contrary to historic hydrology with
corresponding changes in the plant communities from water intolerant to water tolerant plants such
as black willow, bald cypress, tupelo, green ash, water hickory, and button bush.
CLIMATE CHANGE AND GLOBAL WARMING
Global climate change poses risks to human health and to terrestrial and aquatic ecosystems.
Important economic resources such as agriculture, forestry, fisheries, and water resources also
may be affected. Warmer temperatures, more severe droughts and floods, and sea level rise
could have a wide range of impacts. All these stresses can add to existing stresses on resources
caused by other influences such as population growth, land-use changes, and pollution.
According to data from the National Oceanic and Atmospheric Administration (NOAA) and
National Aeronautics and Space Administration (NASA), the Earth's average surface
temperature has increased by about 1.2 to 1.4 degrees Fahrenheit since 1900. The ten
warmest years in the last century have all occurred within the past 15 years, with the warmest
two years being 1998 and 2005. Some climate models, based on emissions of greenhouse
gases, primarily carbon dioxide(CO2), methane, and nitrous oxide, predict that average surface
temperatures could increase from 2.5 to 10.4o F by the end of the 21st century.
Draft Comprehensive Conservation Plan 27
Table 1. Climatological normals for the years 1971-2000 from the National Weather
Service station at El Dorado Airport (032300).
Month
N O R M A L
Mean
(°F)
Minimum
(°F)
Maximum
(°F)
Rainfall
(inches)
Snowfall
(inches)
Jan 43.6 32.9 54.3 4.93 1.10
Feb 48.3 36.3 60.3 4.24 0.40
Mar 56.4 43.9 68.8 5.15 0.16
Apr 63.7 51.0 76.4 4.55 0.0
May 71.5 60.1 82.8 5.49 0.0
Jun 78.4 67.4 89.3 5.18 0.0
Jul 82.0 71.2 92.7 4.13 0.0
Aug 81.2 69.8 92.5 3.22 0.0
Sep 75.1 63.5 86.7 3.29 0.0
Oct 64.4 51.6 77.1 4.33 0.0
Nov 53.8 42.2 65.3 4.80 0.01
Dec 46.1 35.3 56.9 4.80 0.31
Annual 63.7 52.1 75.3 54.11 2.00
Table 2. Climatological normals for the years 1971-2000 from the National Weather
Service station at Crossett (031730).
Month
N O R M A L
Mean
(°F)
Minimum
(°F)
Maximum
(°F)
Rainfall
(inches)
Snowfall
(inches)
Jan 41.3 29.5 53.1 5.81 0.77
Feb 46.0 33.0 58.9 5.27 0.30
Mar 53.7 40.2 67.1 5.95 0.11
Apr 61.0 47.1 74.8 5.61 0.0
May 69.1 56.2 82.0 8.82 0.0
Jun 76.5 64.2 88.8 4.60 0.0
Jul 80.2 68.2 92.1 4.04 0.0
Aug 79.4 66.7 92.1 3.16 0.0
Sep 73.1 59.9 86.3 3.26 0.0
Oct 62.0 47.1 76.9 4.19 0.0
Nov 52.0 39.0 64.9 4.96 0.0
Dec 44.1 32.1 56.0 5.38 0.13
Annual 61.5 48.6 74.4 58.05 0.83
28 Felsenthal and Overflow National Wildlife Refuges
Increases in atmospheric CO2 are attributed largely to human activities, which have grown
rapidly since 1945. The burning of fossil fuels adds 5.6 billion tons of carbon and deforestation
contributes another 0.4 to 2.5 billion tons of carbon to the atmosphere each year.
Global warming, attributed to the melting of glaciers and ice sheets, will cause the sea levels to
rise. Globally, the sea level has risen 4-10 inches during the past century. NASA estimates
that yearly, 50 billion tons of ice is melting from the Greenland ice sheet. NASA aerial surveys
show that more than 11 cubic miles of ice is disappearing from the ice sheet annually.
Considering that land less than 10 meters above sea level contains 2% of the world's land
surface but 10% of its population, major impacts could be felt by large numbers of people living
on the low-lying coastlands, particularly along the Gulf and East Coast states.
In addition to the rising seas, the effects of climate change and global warming will be changes
in weather/rainfall patterns, decreases in snow and ice cover, and stressed ecosystems. For
the southeastern U.S. and the Felsenthal-Overflow region, this can mean extreme precipitation
events; greater likelihood of warmer/drier summers and wetter/reduced winter cold; and
alterations of ecosystems and habitats due to these changes in weather patterns—to name but
a few possibilities. For example, a recent study of the effects of climate change on eastern
U.S. bird species concluded that as many as 78 species of birds could decrease by at least
25%, while as many as 33 species could increase in abundance by at least 25% due to climate
and habitat changes.
GEOLOGY AND TOPOGRAPHY
There are six major physiographic divisions in Arkansas: the Ozark Mountains, the Arkansas
River Valley, the Ouachita Mountains, the West Gulf Coastal Plain, the Mississippi Alluvial
Valley, and Crowley's Ridge. The first three divisions are part of a larger region called the
Interior Highlands physiographic region of northwest Arkansas, and the latter three are part of
the Gulf Coastal Plain physiographic region of southern and eastern Arkansas.
The rock and sediments of the Gulf Coastal Plain are much younger (of Cenozoic age) than
those of the Interior Highlands (of Paleozoic age). The Interior Highlands are generally
characterized as hilly to mountainous topography on Paleozoic rock substrates dominated by
upland hardwood and upland pine-hardwood forests, with extensive prairies. The Gulf
Coastal Plain is a belt of land that had been inundated by the Gulf of Mexico at some time
since the Jurassic period, generally during the Tertiary period or more recently. The surface
geology includes areas of sandstone, limestone, or chalk, but more typically consists of
unconsolidated sand, grave, or clay sloping gently from toward the south and east. The
surface is underlain by rocks that range from unconsolidated to poorly consolidated clastic
rocks. The oldest rocks are Jurassic in age and are deeply buried in the subsurface. The
rocks dip gently toward the Gulf of Mexico or toward the Mississippi embayment. Diapiric
flowage of salt strata, which is caused by the salt being overloaded by thick accumulations of
younger sedimentary strata, has resulted in the formation of salt domes. Typical plant cover
is pine forest on sandy hills and bottomland hardwood forest along streams and rivers. The
Felsenthal and Overflow refuges lie within this southern and eastern physiographic region.
Specifically, Felsenthal NWR lies within the West Gulf Coastal Plain physiographic division;
and Overflow NWR lies within the Mississippi Alluvial Valley physiographic division.
Draft Comprehensive Conservation Plan 29
Felsenthal National Wildlife Refuge
The surface geology of the West Gulf Coastal Plain in the vicinity of Felsenthal NWR is
characterized by unconsolidated deposits of sand, gravel, silt, and clay from the ocean bottom,
beaches, and estuaries that have eroded into rolling, sandy hills that were covered with pine
forests. The surface geology is characterized by Tertiary and Cretaceous sediments which
underlie most of this area. These sedimentary rocks, deposited mostly in a marine
environment, were later uplifted and now tilt seaward. The predominant Quaternary units are
Pleistocene (Qt) and Holocene (Qal) alluvial deposits. The predominant Tertiary unit, lying
mostly to the west of the refuge, is the Claiborne Group (Tc).
The topography of this area can be described as nearly level or gently rolling uplands, terraces,
and floodplains. The area is composed of rolling plains that are broken by nearly flat fluvial
terraces, bottomlands, sandy low hills, and low cuestas. The terrain is unlike the much more
rugged Ouachita Mountains to the north or the flatter, less dissected Mississippi Alluvial Valley
to the east. Uplands are underlain by poorly-consolidated, Tertiary- through Cretaceous-age,
coastal plain deposits and marginal marine sediments. These sediments were laid down as the
Gulf of Mexico opened and North America’s southern continental margin subsided. The
bottomlands and terraces are veneered with Quaternary alluvium or windblown silt deposits and
loess. The lithologic mosaic is distinct from the Paleozoic rocks of the Ouachita Mountains and
the strictly Quaternary deposits of the Mississippi Alluvial Plain. The uplands are intricately
dissected by streams. Broad floodplains and terraces are along some streams. Elevation
typically ranges from about 60 to 90 feet above mean sea level, increasing gradually from
southeast to northwest. Local relief is generally less than 10 feet.
Overflow National Wildlife Refuge
The geology of the Mississippi Alluvial Valley in the vicinity of Overflow NWR is bedrock,
consisting of Tertiary and Cretaceous sands formed as beach deposits during the retreat of the
Cretaceous ocean from the midsection of the U.S. Alluvial deposits from flooding and lateral
migration of the Arkansas and Ouachita Rivers typically lie above the bedrock. The area is
veneered by Quaternary alluvium, loess, glacial outwash, and lacustrine deposits. The
sediments are sandy to clayey fluvial deposits of Holocene (Qcm and Qso) to late Pleistocene
(Qt) age and are many meters thick. In some areas late Pleistocene terrace deposits are within
several meters of the present surfaces, but they do not crop out.
The landforms in the area are level or depressional to very gently undulating alluvial plains,
backswamps, oxbows, natural levees, and terraces. River terraces, swales, and levees provide
limited relief. Nearly flat, clayey, poorly-drained soils are widespread and characteristic.
Streams and rivers have very low gradients and fine-grained substrates. Many reaches have ill-defined
stream channels. Landform shapes range from convex on natural levees and
undulating terraces to concave in oxbows. Landform shapes differentiate water-shedding
positions from water-receiving positions, both of which affect soil formation and hydrology.
Elevations generally vary from 90 to 110 feet above mean sea level. In the hilly areas near
Beech Creek, elevations up to 150 feet are common. Maximum local relief is about 10 feet, but
relief is considerably lower (slopes less than 1%) in most of the area east of the West Gulf
Coastal Plain escarpment.
30 Felsenthal and Overflow National Wildlife Refuges
SOILS
Soils directly influence the kind and amount of vegetation and the amount of water available; in
this way they indirectly influence the kind of wildlife that can live in an area. Soils are organized
into a taxonomic classification system by the U.S. Department of Agriculture, Natural Resources
Conservation Service in which each soil is categorized by order, suborder, great group,
subgroup, family, and soil series. Nationwide, there are twelve soil orders, two of which—
Alfisols and Inceptisols—are predominantly found on the Felsenthal and Overflow refuges. The
soils in the area dominantly have a thermic soil temperature regime, a hydric soil moisture
regime, and siliceous or mixed mineralogy. They are very deep, poorly to very poorly drained,
and loamy or clayey. Within these two orders there are two dominant soil series found on
Felsenthal NWR and four dominant soil series found on Overflow NWR.
Felsenthal National Wildlife Refuge
The primary soil type in Felsenthal NWR is the Guyton series and Una silty clay loam. The
Guyton series consists of loamy poorly drained, slowly permeable soils that formed in silty marine
sediments. These soils are formed in alluvium with high silt content. These level soils are found
on broad uplands flats and flood plains (bottom lands and stream terraces) subject to frequent or
occasional flooding. They are often saturated with water in the late winter and spring. The native
vegetation found here is mixed hardwoods and pines. Una soil is formed in acid clayey alluvium.
These soils are poorly drained, with very slow runoff and permeability and are found on
floodplains of streams. During the winter and early spring, these soils are often flooded and the
water table is within a foot of the surface. Most areas with this type soil are pasture or forest, with
the forested and wooded areas being bottomland hardwoods. The Guyton soil series is found in
the Alfisols order, Aqualfs suborder, and the Glossaqualfs great group. The Una soil series is in
the Inceptisols order, Aquepts suborder, and Epiaquepts great group.
Overflow National Wildlife Refuge
Where the bottomland hardwoods have not been cleared, the primary soil type is Perry Clay, a
hydric soil, highly impervious to water percolation. There are inclusions of silty clays on the
higher elevations such as Portland Clay and as elevation increases. Perry and Portland soils
are poorly drained soils, respectively. They are found in level, clayey and loamy soils on bottom
lands. Perry soils have clay surface texture, and Portland soils have silt loam or silty clay loam
surface texture. Hebert silt clay is also prominent. On the highest elevations, Rilla sandy loam
is the dominant soil type. Herbert and Rilla soils are somewhat poorly drained and well drained
soils, respectively. They are found in level to undulating, loamy soils on bottom lands. The
Perry and Portland soil series are both in the Inceptisols order, Aquepts suborder, and
Epiaquepts great group. The Rilla soil series is in the Alfisols order, Udalfs suborder, and
Hapludalfs great group. The Herbert soil series is in the Alfisols order, the Adalfs suborder, and
the Ochraqualfs great group.
The dominant soil series of Desha County, where the Oakwood Unit is located, is Sharkey and
Desha clays. The Sharkey soil is poorly drained, and the Desha soil is somewhat poorly
drained. When dry, these soils contract and crack, and when wet, they expand and seal over.
Runoff is very slow, and wetness is a severe hazard. The Sharkey-Commerce-Coushatta soil
association is frequently flooded and is extensive in the eastern part of Desha County. This soil
is well suited to hardwood and wildlife habitat and not suitable for cultivation. Sharkey clay
occurs primarily in the northern part of the county. It has a high shrink-swell potential, and
permeability is very slow except when the soil is cracked.
Draft Comprehensive Conservation Plan 31
HYDROLOGY AND WATER QUALITY
Groundwater
Two major aquifer systems provide groundwater in southeastern Arkansas: the Surficial Aquifer
System and the Mississippi Embayment Aquifer System (encompassing the Sparta Aquifer). The
Surficial Aquifer System is the uppermost aquifer system in the region. It consists of alluvial
aquifers and includes one major and three minor aquifers: the Mississippi River Valley aquifer (a
highly productive and the most important aquifer); and three minor aquifers (the Arkansas River,
the Ouachita-Saline Rivers, and the Red River alluvial aquifers). These surficial aquifers consist
of unconsolidated to poorly consolidated Coastal Plain strata of gravel, sand, silt and clay of
Holocene age; and are capable of yielding large quantities of water to wells. The Mississippi
Embayment Aquifer System is made up of poorly consolidated sedimentary rocks of Late
Cretaceous to middle Eocene age, and underlies the Surficial Aquifer System. The Mississippi
Embayment Aquifer System is the most widespread system in the Coastal Plain and it thickens
with depth as it extends toward the Gulf of Mexico into the deep subsurface.
Groundwater provides over 60% of the total freshwater withdrawn in Arkansas. The majority of
groundwater withdrawals in southeastern Arkansas are from the shallower and more
transmissive surficial alluvial aquifer because it is more cost effective to pump. However, water-level
declines in the alluvial aquifer are causing decreased well yields. Withdrawals of large
quantities of groundwater (the majority of which is used for irrigated agriculture like rice and
soybeans) have not only lowered water levels, but also decreased the saturated thickness of
aquifers, and even altered patterns of regional groundwater flow. Within the Mississippi
Embayment Aquifer System, the Sparta aquifer (an aquifer of regional importance in
southeastern Arkansas) is increasingly used to supplement supplies needed for crop irrigation.
Wells in the Sparta aquifer (excluding those wells located within areas of large drawdowns)
generally yield 100 to 500 gallons per minute (gal/min). In 2000, approximately 85 percent of
total groundwater use in southeastern Arkansas came from the alluvial aquifer with the
remaining 15 percent from the Sparta aquifer. Long-term pumping stresses in the Sparta
aquifer have resulted in reduced amounts of water in storage, decreased well yields, regionally
extensive water-level declines, and the formation of regional-scale cones of depression such as
the cone that has formed between El Dorado, Arkansas, and Monroe, Louisiana. In Union
County, the Sparta aquifer has been used increasingly since development began in the early
1920s, resulting in water-level declines of more than 360 feet (ft) in some areas. Cones of
depression continue to grow. Extreme drawdowns have resulted in increased chloride
concentrations of some Sparta aquifer wells in Union County because of upcoming of brackish
water from below. In response to the declining water levels and degraded water quality, the
Arkansas Natural Resources Commission designated the Sparta aquifer as a Critical Ground-
Water Area in five counties of southern Arkansas in 1996.
The groundwater resources in Overflow NWR are very limited, where needed most, in the
waterfowl sanctuary. The alluvial aquifer is approximately 60 to 80 feet deep and there is
only enough water to use 15 horsepower electric motors to pump an average of 400 -600
gallons per minute. With a well pumping in this range, the cooperative farmer can only
irrigate 40-60 acres of rice at a time. This greatly limits the amount of agricultural crops that
are grown and the quality and quantity of moist soil vegetation production. The groundwater
can sometimes be supplemented by the small relift pump on Overflow Creek that can be
utilized to pump surplus beaver dam water to crops. A portable relift pump can be used to
also utilize surface water from Flat Slough Ditch.
32 Felsenthal and Overflow National Wildlife Refuges
Surface Water
The Ouachita-Saline River basin which drains Felsenthal and Overflow NWRs is part of the
dynamic Surficial Aquifer and the Mississippi Embayment Aquifer hydrological system that
includes interactions between aquifers, streams, reservoirs and wetlands. Many tributary
streams receive a substantial contribution of water from groundwater base flow during dry
periods and withdrawal of groundwater can, under certain condition, also result in reduction in
surface water flow. The Felsenthal and Overflow NWRs lie within the Lower Ouachita River
watershed. Located in the Coastal Plain, the Lower Ouachita and the Saline Rivers are the
primary sources of surface freshwater for Felsenthal NWR. Located in the southern portion of
the Mississippi Alluvial Valley, Overflow Creek (and Bayou Bartholomew) are the primary
sources of freshwater for Overflow NWR. These three rivers (Lower Ouachita, Saline and
Bayou Bartholomew) and their tributaries drain both the Felsenthal and Overflow NWRs, as well
as large portions of southeastern Arkansas. The mean flow of the Ouachita River, the Saline
River, and Bayou Bartholomew, respectively, is: 7700 cfs (near Camden), 2600 cfs (near Rye);
and 565 cfs at Garrett Bridge. The State of Arkansas has designated the Lower Ouachita River
and it tributaries, the Saline River and its tributaries, and Bayou Bartholomew and its tributaries
as all suitable for the propagation of fish and wildlife; primary and secondary contact recreation;
and public, industrial and agricultural water supplies.
Felsenthal National Wildlife Refuge
The Ouachita River's source is found in the Ouachita Mountains of west central Arkansas near
the Oklahoma border and flows south-south east 600 river miles before joining the Black and
Red rivers in north-central Louisiana. The Ouachita basin covers over 10,000 square miles of
drainage area. The Saline River is about 204 stream miles long and is a tributary to the
Ouachita River. It is the last free-flowing river in the Ouachita drainage basin. Its origin is in the
Ouachita Mountains in central Arkansas and it flows southward until it flows into the Ouachita
River at Felsenthal NWR, forming a delta-type bayou. The Saline River basin covers about
3,350 square miles of drainage area. Lapile Creek, Lapoile Creek, and Caney Bayou (Blue
Lake Slough and Deep Slough) drain the western part of the refuge and flow ultimately into the
Ouachita River. Eagle (L'Aigle) Creek and Charivari Creek drain the northern portion of the
refuge and Big Brushy Creek drains the eastern portion of the refuge. These three drainages
flow into the Saline River.
Section 303(d) of the Clean Water Act requires states to assess the water quality and prepare a
list of impaired waters. The lower Ouachita River and Saline River, including Felsenthal NWR,
have impaired water quality due to mercury contamination and are listed under Section 303(d)
of the Clean Water Act. This has resulted in the issuance of fish consumption advisories for
about 66 miles of the lower Ouachita River and about 90 miles of the lower Saline River.
Historically the oil, brine, and bromine extraction industries have contributed point and nonpoint
source contamination (high ammonia, nutrients, and dissolved solids) to waters in the area.
Recent management practices have improved water quality for these parameters. In the vicinity
of Felsenthal NWR, elevated zinc and copper concentrations in the Ouachita River are limiting
aquatic life; and high concentrations of copper, beryllium and dissolved solids in the Saline
River are limiting aquatic life and use of the river for drinking water and a source of water for
agriculture and industry.
Draft Comprehensive Conservation Plan 33
Overflow National Wildlife Refuge
Overflow Creek provides the principal drainage to Overflow NWR. It flows the length of the
refuge from north to south and ultimately to its confluence with Bayou Bartholomew, a short
distance below the Louisiana state line. Bayou Bartholomew is purportedly the longest bayou in
the U.S. and flows into the Ouachita River near Sterlington, Louisiana. It is approximately 359
miles long with a drainage area of about 1,700 square miles. The Overflow Creek watershed
encompasses approximately 98 square miles. Beech Creek on the north end, Hill Slough on
the south end, and Billotis Slough, Flat Slough, Oxbone Slough and Gaines Slough on the east
side are the major tributaries of Overflow Creek within the refuge. Historically, during late
summer and early fall, the tributaries and sloughs to Overflow Creek generally become
extremely low or dry leaving only a few deep holes and ponds.
Several segments of Overflow Creek have been altered by private landowners. These
alterations consist of levees, weirs, road crossings, drainage ditches, channel excavation, and
inter-basin transfers to and from Bayou Bartholomew and Bearhouse Creek. Channel
excavation of tributary streams has increased the frequency and duration of flooding of Overflow
Creek and the refuge woodlands. The construction of catfish ponds and the advent of large
scale land leveling on lands east of and adjacent to the refuge has similarly impacted the
hydrology of the watershed. On adjacent lands to the west owned by Koch Forestry Products,
formerly Plum Creek Timber Co. Inc. (formerly Georgia Pacific), an increase in clearcutting and
a shifting to shorter timber management rotations has increased runoff and siltation.
Consequently, Overflow Creek has poor water quality due to erosion and siltation/turbidity
problems which impair aquatic life in the stream. In addition, the entire stretch of Bayou
Bartholomew, which drains the eastern most portion of Overflow NWR, has been assessed as
not meeting its aquatic life uses due to siltation and turbidity, from nonpoint pollution generated
by row crop agriculture.
Besides Overflow Creek, a major source of water flowing into the refuge comes from Flat
Slough Ditch. This ditch was dug in the 1960s to provide agricultural drainage to the
surrounding area and continued into the forested area until it reached the confluence of
Overflow Creek. At that point, dredging continued down the creek to the levee that creates
the greentree reservoir (GTR). At the same time, the landowners dredged a small portion of
Overflow Creek upstream from Flat Slough Ditch until the dragline nearly sunk as it
approached a deep pool of the creek known as the “grinnel hole”. From this point northward
water quality is quite good due to less agricultural runoff and the filtering effect of the beaver
dams and aquatic vegetation. In the Flat Slough Ditch, water quality is severely impaired
due to the large volume of runoff associated with agriculture and affects Overflow Creek
below its connection with Flat Slough Ditch.
Water quality on Overflow NWR is very similar to other streams in the Mississippi Alluvial Valley
where channelization/dredging have taken place. The water is very turbid and contaminated
with residuals of organochlorines and pesticides. These chemicals were identified in 2001 as
results of a study conducted by North Carolina State University using semi permeable
membrane devices which trapped chemical residues. Turbidity was measured and documented
as well. The study was entitled “Chemical Contamination at National Wildlife Refuges in the
Lower Mississippi River Ecosystem.”
Stream gradients in the area are low (approximately 1 foot per mile) and summer flow in many
small, tributary streams is limited or nonexistent, but enduring pools may occur. Most of the
drainage of Bayou Bartholomew watershed, which is near Overflow NWR, is in cropland and
34 Felsenthal and Overflow National Wildlife Refuges
receives heavy treatments of insecticides and herbicides. Soybeans, cotton, and rice are the
major crops, and aquaculture is also important. Agricultural runoff containing fertilizers,
herbicides, pesticides, and livestock waste have degraded surficial water quality.
Concentrations of total suspended solids, total dissolved solids, total phosphorus, ammonia
nitrogen, sulfates, turbidity, biological oxygen demand, chlorophyll a, and fecal coliform are
high in the rivers, streams, and ditches. Concentrations are often much greater than
elsewhere in Arkansas and are greatest during the spring, high-flow season. Also, mercury
contamination of fish impairs about 43 miles of Bayou Bartholomew upstream of Overflow
NWR. Under Section 303(d) of the Clean Water Act, the State of Arkansas has listed
Overflow Creek as a water quality limited stream due to the adverse effects of siltation and
turbidity on aquatic life in the stream. These (and other) water quality considerations have
resulted in Overflow NWR being closed to fishing.
AIR QUALITY
The Clean Air Act of 1970 (as amended in 1990 and 1997) requires the U.S. Environmental
Protection Agency (EPA) to implement air quality standards to protect public health and welfare.
National Ambient Air Quality Standards (NAAQS) were set for six pollutants commonly found
throughout the United States: lead, ozone, nitrogen oxides (NOx), carbon monoxide (CO), sulfur
dioxide (SO2), and particulate matter less than 10 and 2.5 microns in diameter (PM10 and PM2.5).
The State of Arkansas Department of Environmental Quality (ADEQ), Air Division, conducts
monitoring to satisfy Clean Air Act monitoring requirements. The Arkansas Ambient Air
Monitoring Network currently collects data at 20 monitoring locations in 15 counties. Arkansas
is only one of a handful of states in the country that currently and consistently meets all federal
air quality standards for criteria pollutants.
The two nearest air quality monitoring sites in the vicinity of the Felsenthal and Overflow refuges
are in El Dorado (Union County) and Crossett (Ashley County). The data is displayed in Table 3
for 2005-2007. Areas that meet the NAAQS standards are designated “attainment areas,” while
areas not meeting the standards are termed “nonattainment” areas. The monitoring results
indicate that both areas (and assumably the Felsenthal and Overflow NWRs) qualify as
attainment areas for all monitored pollutants.
The Air Quality Index (AQI) is a summary index for reporting daily air quality. It tells how clean
or polluted the air is, and what the associated health effects of concern might be. The AQI
focuses on health effects that may be experienced within a few hours or days after breathing
polluted air. The EPA calculates the AQI for five major air pollutants regulated by the Clean Air
Act: ground-level ozone, particle pollution (also known as particulate matter), carbon monoxide,
sulfur dioxide, and nitrogen dioxide. (Because all areas of the United States are currently
attaining the NAAQS for lead, the AQI does not specifically address lead.) For each of these
pollutants, the EPA has established national air quality standards to protect public health.
Based on this index, in 2007, the air quality in the Ashley County area was categorized as
"good" 77% of the time and as "moderate" 23% of the time. The Union County area’s air quality
was categorized as "good" 92% of the time and as "moderate" 8% of the time. There were no
"unhealthy for sensitive groups" reports for either of the monitoring locations.
Draft Comprehensive Conservation Plan 35
Table 3. Arkansas ambient air monitoring data.
Air Quality Statistics by County, 2007
State/County
2000
Population
CO
8-hr
(ppm)
Pb
Qmax
(μg/m3)
NO2
AM
(ppm)
O3
1-hr
(ppm)
O3
8-hr
(ppm)
PM10
24-hr
(μg/m3)
PM2.5
Wtd AM
(μg/m3)
PM2.5
24-hr
(μg/m3)
SO2
AM
(ppm)
SO2
24-hr
(ppm)
AR Ashley County 24209 ND ND ND ND ND ND 12.0 25 ND ND
AR Union County 45629 ND ND ND ND ND ND 12.6 26 0.003 0.006
Air Quality Statistics by County, 2006
State/County
2000
Population
CO
8-hr
(ppm)
Pb
Qmax
(μg/m3)
NO2
AM
(ppm)
O3
1-hr
(ppm)
O3
8-hr
(ppm)
PM10
24-hr
(μg/m3)
PM2.5
Wtd AM
(μg/m3)
PM2.5
24-hr
(μg/m3)
SO2
AM
(ppm)
SO2
24-hr
(ppm)
AR Ashley County 24209 ND ND ND ND ND ND 13.6 28 ND ND
AR Union County 45629 ND ND ND ND ND ND 11.8 25 0.003 0.008
Air Quality Statistics by County, 2005
State/County
2000
Population
CO
8-hr
(ppm)
Pb
Qmax
(μg/m3)
NO2
AM
(ppm)
O3
1-hr
(ppm)
O3
8-hr
(ppm)
PM10
Wtd AM
(μg/m3)
PM10
24-hr
(μg/m3)
PM2.5
Wtd AM
(μg/m3)
PM2.5
24-hr
(μg/m3)
SO2
AM
(ppm)
SO2
24-hr
(ppm)
AR Ashley County 24209 ND ND ND ND ND ND ND IN IN ND ND
AR Union County 45629 ND ND ND ND ND ND ND 14.9 38 0.002 0.007
36 Felsenthal and Overflow National Wildlife Refuges
BIOLOGICAL RESOURCES
HABITAT
Felsenthal National Wildlife Refuge
Felsenthal NWR is located in an extensive natural depression and low-lying area dissected by an
intricate system of rivers, creeks, sloughs, buttonbush swamps and lakes throughout a vast
bottomland hardwood forest that gradually rises to an upland forest community (Figure 7). The
region's two major rivers, the Saline and Ouachita, flow through the refuge. Historically, periodic
flooding of the "bottoms" (bottomland hardwoods) during winter and spring provided excellent
wintering waterfowl habitat. These wetlands, in combination with the pine and upland hardwood
forests on the higher ridges, support a wide diversity of native plants and animals. The habitat
types represented on Felsenthal NWR are shown in Table 4.
Table 4. Felsenthal NWR habitat types and their acreages.
Habitat Types Acres
Permanent Water 15,000
Forestland 49,383
Pine 9,490
Pine-Hardwood 705
Bottomland Hardwood 39,000
Upland Hardwood 188
Open Fields, Prairies and
Nonproductive Areas 617
TOTAL 65,000
During winter, up to 21,000 acres of the bottomland hardwoods can potentially be flooded to
provide wintering waterfowl habitat.
Water Level Management. Carefully timed flooding of hardwood forest communities, commonly
referred to as greentree reservoir (GTR) management, provides thousands of acres of habitat
for wintering waterfowl. Felsenthal NWR is home to the world's largest GTR consisting of the
15,000-acre Felsenthal Pool that is more than doubled to 36,000 acres during wintertime
flooding. The primary forest type in the GTR is overcup oak-water hickory, followed by
somewhat less frequently flooded types in which nuttall oak, willow oak, and/or sweetgum
predominate. Additional species include persimmon, hawthorns, deciduous holly, swamp privet,
water oak and an occasional baldcypress.
Flooding of the GTR usually begins in mid-November with expectations that water levels will
reach desired levels by the end of December. Water levels are then allowed to slowly recede
until they reach desired draw down levels in the late spring. As part of the process of
preparation of this CCP, the water manipulation schedule for the GTR will be reviewed and
modified as appropriate to provide flexibility and support restoration of desirable tree species in
the GTR. See the discussion on Greentree Reservoir Management in the Ecological Threats
and Problems section of Chapter II, Refuge Overview.
Water level management in other impoundments, such as moist soil units, stimulates the growth
of native wetland plant species and an abundance of insects, crustaceans and mollusks, all
highly favored foods of migratory waterfowl, wading birds and shorebirds.
Draft Comprehensive Conservation Plan 37
Figure 7. General habitat types on Felsenthal National Wildlife Refuge.
38 Felsenthal and Overflow National Wildlife Refuges
Forest Land Management. Felsenthal NWR's forest management practices focus on
providing excellent conditions for the variety of wildlife living in the forest. Prescribed burning,
thinning, regeneration and stand improvement are some of the techniques used to enhance
and maintain optimum habitat conditions. In the upland areas, the timber is managed primary
for the endangered red-cockaded woodpecker where artificial nest inserts are placed in
mature pine trees to supplement suitable cavities. Felsenthal NWR has 49,383 acres of
forestland under active management, as shown in Table 4. This long-term program is
designed to provide a diversity of habitat conditions to meet the needs of a full spectrum of
indigenous wildlife species with the main emphasis on endangered species and waterfowl.
Based on the Timber-Wildlife Management Plan (revised in 1995), the refuge uses biologically
sound silvicultural practices to provide a diversity of forest habitat. Through commercial forest
thinning and improvements cuts, the forest environment is managed to provide habitat for
endangered red-cockaded woodpeckers, resident and wintering waterfowl, other migratory
birds and numerous species of resident wildlife.
Fire Management. Prescribed fire is a primary habitat management tool on the 9,490 acres of
pine forest on Felsenthal NWR. The objectives of the refuge’s prescribed burning program are
(1) wildlife habitat improvement for the red-cockaded woodpeckers and other species, (2) fuel
reduction, (3) site preparation, and (4) understory management. The prescribed burns are
managed on a rotationtal basis. The refuge rotates the area burned every year so that all areas
included in the burn program are burned once every four years.
Overflow National Wildlife Refuge
Overflow NWR is a 13,000-acre plus wetland complex consisting of approximately 9,000 acres of
seasonally flooded bottomland hardwood forests and 3,600 acres of prior converted agricultural
fields, impoundments and croplands (Figure 8). Most of the land within the refuge is classified as
stream floodplain. Upland hardwoods and pine occur on the west boundary access points and on
a very narrow strip of land along the escarpment which separates the Mississippi Delta from the
Coastal Plain. The habitat types represented on Overflow NWR are shown in Table 5.
Table 5. Overflow NWR habitat types and their acreages.
Habitat Types Acres
Cropland/Moist Soil Rotation 600
Cropland only 245
Grassland Management 35
Moist Soil only 520
Reforested 2,020
Marsh 50
CRP Pine (recent purchase) 179
Beaver Ponds & Scrub/Shrub Wetlands 1,500
Bottomland Hardwood Forest 8,625
Upland Hardwood/Pine 175
Administrative 24
TOTAL 13,973
Draft Comprehensive Conservation Plan 39
Figure 8. General habitat types on Overflow National Wildlife Refuge.
40 Felsenthal and Overflow National Wildlife Refuges
Water Level Management. Seasonal flooding of the 4,000-acre greentree reservoir (GTR) on
Overflow NWR is conducted annually, generally with a target date between December 10 and
January 1 to achieve maximum pool level. Drawdown is generally initiated at the end of
January if water levels are low enough to access the floodgates. At this time of year, water
levels vary over a wide range due to heavy late winter rainfall or occasionally, a scarcity of
rainfall. During a dry winter, the structure may not be opened until a later date. Water level
management activities are also conducted on croplands and moist soil units to create soil and
water conditions conducive for the germination of desirable plants, to control nuisance
vegetation, and promote the production of invertebrates. The development of a complex of
moist soil management impoundments, agricultural fields and flooded bottomland hardwoods
provides a variety of important foods and habitat types for wintering waterfowl, wading birds,
shorebirds, and secretive marsh birds.
Overflow NWR has a system of 18 separate units in the north sanctuary and two small units
west of the office where water level management takes place. The infrastructure in place for
managing water consists of overflow spillways, metal water control structures, numerous levees,
ditches and wells, and one stationary and one portable relift pump to utilize surface water. A
concrete structure is situated on the Flat Slough Ditch that is capable of flooding much of the
sanctuary by backing excess water through water control structures (WCS) in the appropriate
fields and then closing off the WCS when the desired water level is reached. Then the Flat
Slough structure can be opened with a screw gate or by pulling stoplogs and drained to the
desired level. It should be noted that when water is topped out at the Flat Slough structure
about 80 acres of private land will be flooded as well. The refuge has an agreement with the
neighboring farmer to cooperatively manage this lower 80 acres for moist soil/rice rotation
where the Service will not create crop damage while conducting water management. However,
the location of this farm greatly impedes the refuge from reaching its full water management
potential. At this time the owner is not a willing seller. The refuge also assists adjacent
landowners with crop/moist soil rotations on an additional 145 acres. This is all on an advisory
basis with no written agreements in place.
The other water control structure is the large concrete structure on Overflow Creek with two lift
gates and two slots where stoplogs are utilized for management of the GTR. The four openings
are 6 ft. wide x 9 ft. deep. It is more than adequate for proper drainage of the GTR. Before
water reaches the top of the structure it begins to flow around the end of the levee. This relief
prevents any levee washouts. The levee is one mile long with two concrete overflow spillways.
The water management system at Overflow allows management opportunities for any species
of migratory bird using the general area. It is the discretion of the biologist/manager to design
and implement the plan for emphasis on the various species in the most advantageous
locations. Due to the constraints of weather, written plans have to be modified almost every
year in order to achieve desired conditions for selected bird groups in the planned location.
Flexibility is essential and the biologist must keep several “Plan B’s” in mind to deal with
abnormal or unexpected weather conditions.
Forest Management. The majority of Overflow NWR is bottomland hardwood forest consisting
primarily of willow and overcup oak. Other major kinds of trees that grow on the refuge include
hickories, elms, and green ash. Bald cypress and tupelo gum can also be seen along streams,
channels, and sloughs throughout the refuge. Over time, several segments of Overflow Creek, its
tributaries, and adjoining lands have been subject to alterations consisting of land clearing,
channel excavation, weirs, earthen dams, road crossings, and levees. These activities, in
conjunction with a dense beaver population, have increased the frequency and duration of
Draft Comprehensive Conservation Plan 41
flooding in the forested area, resulting in a radically changed streamside habitat along the major
waterways. What was once an oak/hickory forest has shifted to a more water-tolerant habitat
consisting of buttonbush, swamp privet, water locust, water elm, black willow, green ash, bald
cypress, and water tupelo.
Slightly higher elevations are still flood prone, but are not so severely impacted by beaver dams.
The primary forest species for these sites are overcup oak, willow oak, delta post oak, cedar elm,
green ash and persimmon. Nuttall oaks are noticeably few in number on these sites. The higher
ridges adjacent to Oxbone Slough, Billotis Slough, and Beech Creek are dominated by cherrybark
oak, shagbark hickory, nutmeg hickory, delta post oak, and cow oak. Loblolly pine and upland
hardwoods occupy the higher elevations on the western boundary that abuts the West Gulf Coastal
Plain. About 2,000 acres of marginal farmland have been reforested with a variety of hardwood
species to closely represent the original forest species composition before the land was cleared.
One of the issues which a Forest Habitat Management Plan needs to address is the removal
of invasive pine (pine seeds blowing onto the refuge from the coastal plain and colonizing
hardwood reforested habitats). At the present time, there is no active Forest Habitat
Management Plan in place for Overflow NWR (please refer to the Ecological Threats and
Problems section in Chapter II, Refuge