Okefenokee National Wildlife Refuge Comprehensive Conservation Plan

              N W R
Comprehensive Conservation Plan
Photo provided by
Jim Abernethy’s Scuba Adventures
Okefenokee National Wildlife Refuge - USFWS
Route 2, Box 3330
Folkston, GA 31537
(912) 496-7836 (voice and TDD)
http://okefenokee.fws.gov/
U.S. Fish & Wildlife Service
1 800/344 WILD
http://www.fws.gov
October 2006
U.S. Fish & Wildlife Service
Okefenokee
National Wildlife Refuge
CCoompprreehheennssiivvee CCoonnsseerrvvaattiioonn PPllaann
USFWS Photo
Comprehensive Conservation Plans provide long-term guidance for
management decisions; set forth goals, objectives, and strategies
needed to accomplish refuge purposes; and identify the Fish and
Wildlife Service's best estimate of future needs. These plans detail
program planning levels that are sometimes substantially above
current budget allocations and, as such, are primarily for Service
strategic planning and program prioritization purposes. The plans
do not constitute a commitment for staffing increases, operational
and maintenance increases, or funding for future land acquisition.
Okefenokee National Wildlife Refuge
Comprehensive Conservation Plan
U.S. Department of the Interior
Fish and Wildlife Service
Southeast Region
October, 2006
OKEFENOKEE NATIONAL WILDLIFE REFUGE
COMPREHENSIVE CONSERVATION PLAN
U.S. Department of the Interior
Fish and Wildlife Service
Southeast Region
Atlanta, Georgia
October 2006
Table of Contents i
TABLE OF CONTENTS
SECTION A. COMPREHENSIVE CONSERVATION PLAN
I. BACKGROUND .............................................................................................................................. 1
Introduction..................................................................................................................................1
Purpose And Need For The Plan .................................................................................................1
U.S. Fish And Wildlife Service......................................................................................................2
National Wildlife Refuge System ..................................................................................................2
Okefenokee National Wildlife Refuge...........................................................................................3
Location, Establishment, and Importance ...........................................................................3
Refuge Purpose ..................................................................................................................6
Facilities ..............................................................................................................................7
Facilities ..............................................................................................................................8
Staffing and Funding ...........................................................................................................8
Ecosystems........................................................................................................................9
Threats and Problems.......................................................................................................14
Legal And Policy Guidance ...............................................................................................16
II. REFUGE ENVIRONMENT............................................................................................................ 17
Physical Environment .................................................................................................................17
Climate ..............................................................................................................................17
Historical/Ecological Role of Natural Events .....................................................................19
Physiography and Geology ...............................................................................................22
Soils .................................................................................................................................23
Hydrology ..........................................................................................................................23
Water Quality ....................................................................................................................33
Air Quality.........................................................................................................................34
Biological Environment ...............................................................................................................36
Flora .................................................................................................................................36
Fauna...............................................................................................................................44
Socioeconomic Environment ......................................................................................................59
Early Settlement................................................................................................................59
Land Use...........................................................................................................................60
Adjacent Landowners........................................................................................................61
Demographics ...................................................................................................................63
Financial Benefits..............................................................................................................65
Public Services..................................................................................................................66
Visitor Characteristics .......................................................................................................66
Cultural Environment ..................................................................................................................68
Prehistoric Influences........................................................................................................68
Historical Influences..........................................................................................................69
Modern Influences.............................................................................................................72
III. PLAN DEVELOPMENT................................................................................................................. 81
Planning Process........................................................................................................................81
Planning Issues ..........................................................................................................................82
IV. MANAGEMENT DIRECTION........................................................................................................ 83
Introduction................................................................................................................................83
ii Table of Contents
Refuge Vision............................................................................................................................83
Comprehensive Conservation Plan Summary ...........................................................................83
Goals, Objectives, And Strategies..............................................................................................84
Goal 1 – Wildlife Management..........................................................................................85
Goal 2 – Resource Protection...........................................................................................91
Goal 3 – Wilderness Values..............................................................................................97
Goal 4 – Public Services...................................................................................................99
Goal 5 – Partnerships .....................................................................................................106
Goal 6 – Administration...................................................................................................109
Step-Down Plans .....................................................................................................................113
V. PLAN IMPLEMENTATION ..........................................................................................................115
Introduction ..............................................................................................................................115
Project Summaries...................................................................................................................115
Wildlife Management ......................................................................................................115
Resource Protection .......................................................................................................117
Public Services ...............................................................................................................118
Administration .................................................................................................................119
Staffing ....................................................................................................................................119
Funding ...................................................................................................................................122
Monitoring And Evaluation .......................................................................................................122
Plan Review And Revision .......................................................................................................124
SECTION B. APPENDICES
APPENDIX I. RELEVANT LEGAL MANDATES...............................................................................125
APPENDIX II. FACILITIES ...............................................................................................................139
APPENDIX III. COMPARISON OF VEGETATION CLASSIFICATIONS USED AT OKEFENOKEE
NATIONAL WILDLIFE REFUGE. .............................................................................143
APPENDIX IV. OKEFENOKEE NATIONAL WILDLIFE REFUGE PLANT LIST...............................145
APPENDIX V. OKEFENOKEE NATIONAL WILDLIFE REFUGE WILDLIFE LIST...........................163
APPENDIX VI. WILDLIFE AND LAND COVER ASSOCIATIONS....................................................191
APPENDIX VII. CULTURAL HISTORY OF THE OKEFENOKEE SWAMP AREA...........................195
APPENDIX VIII. CULTURAL RESOURCE SITES ...........................................................................199
APPENDIX IX. PUBLIC SCOPING...................................................................................................205
APPENDIX X. PUBLIC COMMENTS ...............................................................................................247
APPENDIX XI. WILDERNESS REVIEW ..........................................................................................257
Table of Contents iii
APPENDIX XII. DECISIONS AND APPROVALS ............................................................................ 265
Intra-Service Section 7 Biological Evaluation Form..................................................................266
APPENDIX XIII. CONSULTATION AND COORDINATION............................................................. 311
Forestry/Fire Program Review Team .......................................................................................312
Biological Program Review Team ............................................................................................312
Public Services Program Review Team ...................................................................................312
APPENDIX XIV. GLOSSARY OF TERMS AND ACRONYMS ........................................................ 313
APPENDIX XV. LITERATURE CITED............................................................................................. 325
APPENDIX XVI. FINDING OF NO SIGNIFICANT IMPACT............................................................. 335
iv Table of Contents
LIST OF FIGURES
Figure 1. Location of Okefenokee National Wildlife Refuge in relation to other wildlife refuges .........4
Figure 2. Okefenokee National Wildlife Refuge and Wilderness Area................................................5
Figure 3. Approved acquisition boundary for Okefenokee National Wildlife Refuge...........................7
Figure 4. Location of Okefenokee National Wildlife Refuge within the South Atlantic Coastal
Plain physiographic area....................................................................................................10
Figure 5. Location of Okefenokee National Wildlife Refuge within the North Florida Ecosystem .....11
Figure 6. Greater Okefenokee Ecosystem And Its Landowners .......................................................13
State Wildlife Agencies ......................................................................................................14
Figure 7. West to east profile of the sediments under the Okefenokee Swamp and surrounding it
(Hyatt 1984) .......................................................................................................................24
Figure 8. Typical soils series within the Okefenokee National Wildlife Refuge with the associated
vegetation types.................................................................................................................24
Figure 9. Hydrological basins within the Okefenokee Swamp (Loftin 1998) .....................................26
Figure 10. Vegetation cover types of the Okefenokee National Wildlife Refuge (Loftin 1998)............37
Figure 11. Six-class vegetation cover type for Okefenokee National Wildlife Refuge.........................38
Figure 12. Fuel model map for the Okefenokee National Wildlife Refuge ..........................................39
Figure 13. Distribution of RCW clusters on Okefenokee National Wildlife Refuge (2003) ..................52
Figure 14. Distribution of mature pine forest (>60 years) in vicinity of Okefenokee National
Wildlife Refuge...................................................................................................................53
LIST OF TABLES
Table 1. Climatological averages at Camp Cornelia weather station (east entrance).......................18
Table 2. Soil series descriptions at Okefenokee National Wildlife Refuge........................................27
Table 3. Semi-monthly average water levels (msl) at Suwannee Canal Recreation Area
(SCRA) and Stephen C. Foster State Park (SCFSP) between 1990 and 2003 ..................32
Table 4. Air monitoring history at Okefenokee National Wildlife Refuge...........................................35
Table 5. RCW clusters on Okefenokee National Wildlife Refuge in 2003 .........................................50
Table 6. Household income of the four counties the Okefenokee National Wildlife Refuge lies
within. Numbers are based on the 2000 Census................................................................64
Table 7. Educational attainment of the population 25 years and over within the four counties
the Okefenokee National Wildlife Refuge lies within. Numbers are based on
the 2000 Census .................................................................................................................64
Table 8. Revenue sharing amounts paid to each county in lieu of taxes ..........................................65
Table 9. Visitor characteristics as described by Center for Economic Development
Services (2001) ...................................................................................................................67
Table 10. Estimated funding needs to address the issues presented in this plan.............................123
Section A. Comprehensive Conservation Plan 1
SECTION A. COMPREHENSIVE CONSERVATION PLAN
I. Background
INTRODUCTION
The U.S. Fish and Wildlife Service developed this Comprehensive Conservation Plan for Okefenokee
National Wildlife Refuge in Charlton, Ware, and Clinch Counties, Georgia, and Baker County, Florida,
to provide a foundation for the management and use of the refuge over the next 15 years. The plan
is intended to serve as a working guide for the refuge’s management programs and actions.
The plan was developed in compliance with the National Wildlife Refuge System Improvement Act of
1997 and Part 602 (National Wildlife Refuge System Planning) of the Fish and Wildlife Service
Manual. The actions described within this plan also meet the requirements of the National
Environmental Policy Act of 1969. Compliance with this Act was achieved through the involvement of
the public and the preparation of an Environmental Assessment, which was Section B of the Draft
Comprehensive Conservation Plan for the Okefenokee National Wildlife Refuge. When fully
implemented, this plan will strive to achieve the vision and purposes of Okefenokee Refuge.
The plan’s overriding consideration is to carry out the purposes for which the refuge was established.
Fish and wildlife are the first priority in refuge management, and public use (wildlife-dependent
recreation) is allowed and encouraged as long as it is compatible with, or does not detract from, the
refuge’s mission and purposes.
The plan was prepared by a planning team composed of the management staff team at Okefenokee
Refuge, representatives from the Service’s Office of Ecological Services, Georgia Wildlife Federation,
Georgia Department of Natural Resources, Georgia State Parks and Historic Sites, Osceola National
Forest, and a private natural resource consultant. In developing this plan, the planning team
incorporated the input of local citizens and the general public received through a public comment
period and a series of stakeholder and public scoping meetings (Appendix IX).
The plan represents the Service’s preferred alternative and is being put forward after considering
three other alternatives, as described in the Environmental Assessment. After reviewing public
comments and management needs, the planning team developed the preferred alternative in an
attempt to determine how best to manage the refuge. The preferred alternative is the Fish and
Wildlife Service’s course of action for the management of the refuge.
PURPOSE AND NEED FOR THE PLAN
The purpose of this comprehensive conservation plan is to identify the role that Okefenokee Refuge
will play in support of the mission of the National Wildlife Refuge System, and to provide long-term
guidance to the refuge’s management programs and activities. The plan is needed to:
• Provide a clear statement of direction for the future management of the refuge;
• Provide refuge neighbors, visitors, and government officials with an understanding of the
Service’s management actions on and around the refuge;
2 Okefenokee National Wildlife Refuge
• Ensure that the management actions, including land protection and recreational and educational
programs, are consistent with the mandates of the National Wildlife Refuge System Improvement
Act of 1997;
• Ensure that the management of the refuge is coordinated with federal, state, and county plans;
and
• Provide a basis for developing budget requests for the refuge’s operational, maintenance, and
capital improvement needs.
U.S. FISH AND WILDLIFE SERVICE
The U.S. Fish and Wildlife Service is the primary federal agency responsible for the conservation,
protection, and enhancement of the Nation’s fish and wildlife populations and their habitats. Although
the Service shares some conservation responsibilities with other federal, state, tribal, local, and
private entities, it has specific trustee obligations for migratory birds, threatened and endangered
species, anadromous fish, and certain marine mammals. In addition, the Service administers a
national network of lands and waters for the management and protection of these resources.
As part of its mission, the Service manages more than 540 national wildlife refuges covering a total of
more than 95 million acres. These areas comprise the National Wildlife Refuge System, the world’s
largest collection of lands and waters specifically managed for fish and wildlife. The Refuge System
supports over 800 bird species, 220 mammal species, 250 reptile and amphibian species, 1,000 fish
species, and countless species of invertebrates and plants.
NATIONAL WILDLIFE REFUGE SYSTEM
The mission of the 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
mission of wildlife conservation for the Refuge System. The Act states that each refuge shall be
managed to:
• Fulfill the mission of the Refuge System;
• Fulfill the individual purposes of each refuge;
• Consider the needs of fish and wildlife first;
• Fulfill the requirement of developing a comprehensive conservation plan for each unit of the
Refuge System, and fully involve the public in the preparation of these plans;
• Maintain the biological integrity, diversity, and environmental health of the Refuge System;
Section A. Comprehensive Conservation Plan 3
• 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.
Following passage of the Act in 1997, the Service immediately began efforts to carry out the direction
of the new legislation, including the preparation of comprehensive conservation plans for all refuges.
The development of these plans is now ongoing nationally. Consistent with the Act, all refuge
comprehensive conservation plans are being prepared in conjunction with public involvement, and
each refuge is required to complete its own plan within a 15-year schedule.
Approximately 37.5 million people visited the country’s national wildlife refuges in 1998, mostly to
observe wildlife in their natural habitats. As this visitation continues to grow, significant economic
benefits are being generated to the local communities that surround the refuges. Economists have
reported that national wildlife refuge visitors contribute more than $400 million annually to the local
economies. In addition, the National Survey of Fishing, Hunting, and Wildlife Associated Recreation
reports that nearly 40 percent of the country’s adults spent $101 billion on wildlife-related recreational
pursuits in 1996 (U.S. Fish and Wildlife Service 1996).
Volunteerism continues to be a major contributor to the successes of the Refuge System. In 1998,
volunteers contributed more than 1.5 million hours on refuges nationwide, a service valued at more
than $20.6 million.
The wildlife and habitat vision for the national wildlife refuges stresses the following principles:
• The original purpose of the refuge will be implemented.
• Wildlife comes first.
• Ecosystems, biodiversity, and wilderness are vital concepts in refuge management.
• Refuges must be healthy.
• Growth of refuges must be strategic.
• The National Wildlife Refuge System serves as a model for habitat management with broad
participation from others.
OKEFENOKEE NATIONAL WILDLIFE REFUGE
LOCATION, ESTABLISHMENT, AND IMPORTANCE
Okefenokee National Wildlife Refuge is situated in the southeastern Georgia counties of Ware,
Charlton, and Clinch and northeastern Florida's Baker County, roughly between latitudes 30o33’ and
31o05’ North and longitudes 82o07’ and 82o33’ West (Figure 1). The refuge was established in 1936
with the purchase of land and consists presently of 401,880 acres (Figure 2). This plan addresses
management on 395,080 acres. The Conservation Fund donated 6,800 acres to the refuge in
November 2005. Although the refuge owns this donated land, International Paper will manage the
timber and recreation on the land until 2081. The refuge’s approved acquisition boundary includes
4 Okefenokee National Wildlife Refuge
Figure 1. Location of Okefenokee National Wildlife Refuge in relation to other wildlife refuges
Section A. Comprehensive Conservation Plan 5
Figure 2. Okefenokee National Wildlife Refuge and Wilderness Area
6 Okefenokee National Wildlife Refuge
519,480 acres (Figure 3), 117,600 acres beyond the current refuge acres. The primary purpose of the
refuge is to protect the ecological system of the 438,000-acre Okefenokee Swamp. Approximately
371,000 acres of the Okefenokee Swamp wetlands are incorporated into the refuge; and 353,981 acres
within the swamp were designated as wilderness by the Okefenokee Wilderness Act of 1974, making it
the third largest National Wilderness Area east of the Mississippi River. In 1986, the Okefenokee
Refuge was designated by the Wetlands Convention as a Wetland of International Importance.
Okefenokee's natural beauty was first threatened in the 1890s, when attempts were made to drain
the swamp to facilitate logging operations. The Suwannee Canal was dug 11.5 miles into the swamp
from Camp Cornelia. After the failure of this project, known as "Jackson's Folly," other interests
acquired the swamp and began removing timber in 1909, using a network of tram roads extending
deep into the major timbered areas. When logging operations were halted in 1927, more than 423
million board feet of timber, mostly cypress, had been removed from the swamp.
The establishment of Okefenokee Refuge in 1936 marked the culmination of a movement that had
been initiated at least 25 years earlier by a group of scientists from Cornell University that recognized
the education, scientific, and recreational values of this unique area. The Okefenokee Society
formed in 1918 promoted nationwide interest in the swamp. With the support of state and local
interests and numerous conservation and scientific organizations, the Federal Government acquired
most of the swamp for refuge purposes in 1936.
Okefenokee Refuge conserves the unique qualities of the Okefenokee Swamp for future generations
to enjoy. The swamp is considered the headwaters of the Suwannee and St. Marys Rivers. Habitats
provide for threatened and endangered species, such as red-cockaded woodpeckers (Picoides
borealis), wood storks (Mycteria americana), indigo snakes (Drymarchon corais couperi), and a wide
variety of other wildlife species. It is world renowned for its amphibian populations that are bio-indicators
of global health. More than 600 plant species have been identified on refuge lands.
Combining Okefenokee Refuge with Osceola National Forest, private timberlands, and state-owned
forests, more than 1 million contiguous acres provide wildlife habitat and recreational opportunities.
Researchers and students study the resources.
The Georgia communities of Waycross (12 miles north), Folkston (7 miles east), St George (8 miles
southeast), Fargo (5 miles west), and Homerville (20 miles northwest) surround the refuge with
Jacksonville, Florida, 40 miles to the southeast. Nearly 400,000 people visit the refuge each year
making it the 16th most visited refuge in the National Wildlife Refuge System. In 1999, the economic
impact of tourists in Charlton, Ware, and Clinch Counties in Georgia was more than $67 million.
The Okefenokee Swamp has shaped the culture of southeast Georgia. Most residents of Charlton,
Clinch, and Ware Counties have ancestors who once lived or worked in the swamp and view the
swamp as a part of their heritage.
REFUGE PURPOSE
The executive order establishing Okefenokee National Wildlife Refuge in 1937 stated the purpose of
the refuge as “a refuge and breeding ground for migratory birds and other wildlife” (Appendix I).
Section A. Comprehensive Conservation Plan 7
Figure 3. Approved acquisition boundary for Okefenokee National Wildlife Refuge
8 Okefenokee National Wildlife Refuge
FACILITIES
Three primary entrances and two secondary entrances exist on the refuge. The east entrance, located
11 miles southwest of Folkston, Georgia, is the location of the refuge headquarters and is managed
solely by the Fish and Wildlfie Service. Spur 121 is the entrance road to Camp Cornelia and Suwannee
Canal Recreation Area, both part of the east entrance. An administration building just outside the
refuge boundary houses approximately 16 employees while the shop area at Camp Cornelia serves as
a base for 10 additional employees. Two additional employees are located in the visitor center at
Suwannee Canal Recreation Area. A Volunteer Village, located adjacent to the shop area, provides
housing and trailer hookups for volunteers from outside the immediate area. A helibase is also located
nearby to facilitate management flights over the refuge. In association with this helibase, there are 18
helispots that are maintained for safe landing and take off. The Suwannee Canal Recreation Area is
open to the public and offers a newly renovated visitor center and a concession offering swamp tours,
boat rentals, food, and souvenirs. Access is also provided to hiking trails, a wildlife drive, a ¾-mile-long
boardwalk with a 40-foot observation tower, and a restored homestead.
The west entrance to the refuge is via Spur 177 that leads to “The Pocket”, where two employees are
stationed. Just after entering the refuge, two residences serve as office space and housing for
employees, researchers, or volunteers. A shop area is also located at this site. At the end of Spur
177 is Jones Island, the site of Stephen C. Foster State Park, which was established in 1954. This
state park is operated on 82 acres of refuge lands under the provisions of a long-term agreement
(until 2016) with the Georgia State Parks and Historic Sites. The park offers boat tours, boat and
cabin rentals, souvenirs, camping facilities and supplies, a museum, and a picnic area. The refuge
maintains a boathouse on Jones Island.
The refuge's north entrance is via the Okefenokee Swamp Park, which is located about 12 miles
south of Waycross, Georgia. This park is administered by a nonprofit organization on refuge and
state forestlands. The organization offers boat tours, a boardwalk and tower, wildlife and cultural
displays and presentations, and souvenirs.
Kingfisher Landing located between Folkston and Waycross, and the Suwannee River Sill area on
the west side, are considered the secondary entrances into the swamp. Both have a boat ramp. The
Suwannee River Sill area provides bank fishing opportunities.
The refuge has 16 upland management compartments encompassing approximately 15,000 acres
around the perimeter of the swamp. Roads providing access and fire lines are maintained. The
Swamp Perimeter Road was established after the fires of 1954-1955 to provide access around the
swamp. In 1993, the Swamps Edge Break was created to provide a fuels management zone to allow
indirect suppression actions during wildfires. The refuge has responsibility for the maintenance of the
Swamps Edge Break and Swamp Perimeter Road that falls on refuge lands and all bridges on the
Swamp Perimeter Road. The refuge is also responsible for maintaining five man-made dipsites for
fire suppression operations.
Appendix II lists the facilities on and adjacent to the refuge.
STAFFING AND FUNDING
The refuge is currently managed by 31 employees. The permanent personnel include a project
leader, deputy project leader, 3 administration staff, 1 law enforcement staff, 2 biological staff, 6
public use staff, 10 forestry staff, 4 heavy equipment operators, 1 mechanic, and 2 laborers. The
refuge currently has one temporary park ranger.
Section A. Comprehensive Conservation Plan 9
In Fiscal Year 2003, the refuge operated with a budget of $2,026,600 for payroll and operation needs
from refuge operations and fire funds. In addition, $182,800 in special funding were allocated to
address the maintenance backlog and support for the Youth Conservation Corps (YCC), $1,200 were
allocated for safety signs, and $20,000 were allocated for Wildland Urban Interface (WUI) projects.
In Fiscal Year 2002, the refuge was allocated $1,927,500 for payroll and operation needs from refuge
operations and fire funds. In addition, $238,700 in maintenance funding and YCC support, $67,100
for visitor center renovation, and $21,000 for WUI projects were allocated.
ECOSYSTEMS
South Atlantic Coastal Plain Physiographic Area
The Okefenokee Refuge lies within the South Atlantic Coastal Plain physiographic area as
designated by the Partners-in-Flight initiative (Figure 4). The South Atlantic Coastal Plain covers
northeastern Florida, the southern half of Georgia, and the eastern halves of South Carolina and
North Carolina. Its western boundary is the fall line that marks the beginning of the hilly Piedmont
and its eastern boundary is the Atlantic Ocean. As part of a continuous Coastal Plain that extends
from New York to Texas, it has arbitrary boundaries at the Alabama-Georgia border and at the North
Carolina-Virginia border, extending into the southeast corner of Virginia only to capture the Great
Dismal Swamp. Pocosins and Carolina bays are non-alluvial forested wetlands unique to this
physiographic area. Uplands were historically dominated by fire-maintained pine forests, with
longleaf nearer the coast and on sandy soils inland and a mixture of shortleaf, loblolly, and
hardwoods elsewhere (Hunter 2001).
The South Atlantic Coastal Plain has been altered through fire suppression, conversion to other land
uses, and short-rotation pine plantations. Large tracts of fire-maintained pine savannahs are needed
for the health of the high-priority pine and pine-grassland bird species, such as the red-cockaded
woodpecker.
The bottomland hardwood bird community requires large tracts of forest in river systems. The black-throated
green warbler (Dendroica virens) and breeding swallow-tailed kites (Elanoides forficatus)
use these sites. In addition, coastal maritime forest and scrub/shrub habitats not only support most of
the eastern population of painted bunting (Passerina ciris) but also are extremely important for in-transit
migratory birds. Much of this forest has been developed for intensive human use, and what
remains should be maintained (Hunter 2001).
North Florida Ecosystem
The North Florida Ecosystem as designated by the Service based on watersheds includes portions of
south Georgia and most of north and central Florida (Figure 5). The area includes southern
temperate and subtropical climates, numerous physiographic districts, and many unique and widely
varied habitat types. The northern boundary of this ecosystem includes the watersheds of the St.
Marys River and the Suwannee River, including the Okefenokee Swamp. The northeast boundary
begins at Camden County, Georgia, and proceeds down the east coast of Florida to the
Brevard/Indian River county line. The ecosystem then turns west and includes the following counties
as its southern border: Orange, Lake, and Sumter. The western boundary includes all Florida
counties from Sarasota north through Taylor and Jefferson. In Georgia, the ecosystem is inclusive of
all counties east and south of the following: Thomas, Colquitt, Worth, Turner, Ben Hill, Coffee, Ware,
Charlton, and Camden (U.S. Fish and Wildlife Service 1996).
10 Okefenokee National Wildlife Refuge
Figure 4. Location of Okefenokee National Wildlife Refuge within the South Atlantic Coastal
Plain physiographic area
Section A. Comprehensive Conservation Plan 11
Figure 5. Location of Okefenokee National Wildlife Refuge within the North Florida
Ecosystem
12 Okefenokee National Wildlife Refuge
Besides the wetlands of the Okefenokee Swamp, this ecosystem includes barrier islands, xeric scrub,
pine flatwoods, freshwater marshes, lakes, streams and springs, mixed hardwood/pine forests,
cypress swamps and domes, dry prairies, maritime forests, hardwood hammocks, estuarine marshes,
pine rocklands, sandhill woodlands, coastal strands, sawgrass prairies, sloughs, and tree islands.
Okefenokee and Merritt Island National Wildlife Refuges, Ocala and Osceola National Forests,
Canaveral National Seashore, and Timucuan Ecological and Historical Preserve protect a variety of
the habitat types. Other areas are subject to habitat loss from direct destruction, fragmentation, or
the impacts of human activities. The ecosystem team identified the following tools to manage the
North Florida Ecosystem:
• Reliance on and use of the best science and technology;
• Education of peers, associates, clients, and public;
• Active and effective law enforcement;
• Aggressive land protection efforts;
• Strong adherence to regulatory responsibilities;
• Sound public and private land management;
• Strong inter-governmental coordination; and
• Increased private landowner partnerships.
Greater Okefenokee Ecosystem
The Greater Okefenokee Ecosystem includes the Okefenokee Refuge, Osceola National Forest, state-owned
forests, and private timberlands (Figure 6). It encompasses over a million contiguous acres of
suitable habitat for a diversity of wildlife. The Okefenokee Swamp and Pinhook Swamp are two large
wetlands included in this area. Upland pine forests, oak hammocks, and small isolated wetlands cover
the remaining area. Rainfall and fire are the two primary factors governing the landscape.
As part of this ecosystem, the Okefenokee Refuge provides a valuable reservoir of biological
resources that supply the surrounding lands. It is a stronghold for the Florida black bear (Ursus
americanus floridianus). Wading birds abound. Old-growth cypress still exists and longleaf pine
(Pinus palustris) communities are successfully being restored with visions focused on 200-300 years
into the future. Management for the associated wildlife species, such as the endangered red-cockaded
woodpecker, follows this long-term vision.
Understanding the wildlife populations, the quality of the system, and man’s potential impacts on the
system contributes to the well-being of neighboring communities and protects their heritage.
Ecotourism is building in the area.
A unified effort to manage, protect, and promote forest resources in and around the Okefenokee
Swamp has been made through the Greater Okefenokee Association of Landowners, which
recognizes the following:
• Forest resources are the major industries in the area;
• The Okefenokee Swamp is a national treasure and economically and biologically beneficial to the
local communities and the States of Georgia and Florida;
• It is essential to have a coordinating committee for fire protection of public and private resources;
and
• A formal organization of landowners provides an avenue for communications and develops
strength in dealing with area issues.
Section A. Comprehensive Conservation Plan 13
Figure 6. Greater Okefenokee Ecosystem And Its Landowners
14 Okefenokee National Wildlife Refuge
State Wildlife Agencies
A provision of the National Wildlife Refuge System Improvement Act of 1997, and subsequent agency
policy, is that the Fish and Wildlife Service shall ensure timely and effective cooperation and
collaboration with other federal agencies and state fish and wildlife agencies during the course of
acquiring and managing refuges. This cooperation is essential in providing the foundation for the
protection and sustainability of fish and wildlife throughout the Untied States.
Georgia Wildlife Resources Division
The Georgia Wildlife Resources Division is charged with enforcement responsibilities for migratory
birds and endangered species, as well as managing the State’s natural resources. It manages Dixon
Memorial Wildlife Management Area adjacent to the refuge, provides expertise in fisheries
management, and assists in management of hunting on the refuge. The division has also been a
partner in a comprehensive black bear study. The Georgia Wildlife Resources Division was
represented on the core planning team for the draft plan and environmental assessment, the
biological review team, and also served as a presenter at public meetings.
Georgia State Parks and Historic Sites
The Georgia State Parks and Historic Sites is charged with managing state park lands and historic
sites. It manages Stephen C. Foster State Park, located on 82 acres of the refuge. The park
provides visitor services and protection to about 120,000 people each year. It also manages Laura S.
Walker State Park in close proximity to the refuge and the new Suwannee River Visitor Center
downstream from the refuge. Georgia State Parks and Historic Sites was represented on the core
planning team foar the draft plan and environmental assessment, the public use review team, and
also served as a presenter at public meetings.
Florida Fish and Wildlife Conservation Commission
The Florida Fish and Wildlife Conservation Commission is charged with enforcement responsibilities
for migratory birds and endangered species, as well as managing the State’s natural resources. It
manages the Osceola Wildlife Manage Area in close proximity to the refuge and the John Bethea
State Forest Wildlife Management Area adjacent to the refuge. The Florida Fish and Wildlife
Conservation Commission was requested to provide a core team member but declined; however the
Commission played an important role in reviewing the draft plan and environmental assessment.
THREATS AND PROBLEMS
Mining/Oil/Gas
Strip mining for titanium has been proposed on 22,000 acres directly adjacent to the southeastern
boundary of the swamp. The Service has many concerns regarding strip mining and its proximity to
this globally unique resource - The Okefenokee Swamp. Potential impacts include:
• Alternations to water table elevation in the swamp as a result of changes to surface and ground
water quantities and flows of the Trail Ridge;
• Destruction of endangered and rare species and their habitats;
• Destruction of wetlands;
• Reduction of air and water quality through the release of contaminants; and
• Degradation of the wilderness experience for refuge visitors.
Section A. Comprehensive Conservation Plan 15
This same threat was recently eliminated from 16,000 acres adjacent to the northeastern boundary of
the refuge when E.I. DuPont De Nemours and Company, Inc., donated it to The Conservation Fund.
Wetland Management
Numerous threats to the quantity and quality of the water resources of the area may affect wetland
management and its health.
• Water quality is being degraded as a result of increased use of fertilizers and herbicides on
surrounding timberland, contaminant deposition from the atmosphere, and increased water
withdrawals from the aquifer along the coast. This degradation influences the survival of certain
species by limiting food sources, restricting reproduction, and decreasing the health of the entire
ecosystem.
• Although the Suwannee River Sill was constructed to retain water during drought, its greatest
effects appear to be during high water. Due to a series of natural terraces in the swamp, the zone
of influence during low water levels decreases to only about 1 percent of the swamp. An
environmental assessment identified the preferred alternative for managing the sill as a “Phased
removal of concrete water control structures and breaching of the sill in selected locations” that
would restore the natural connection between the swamp and the Suwannee River, and restore
the river flood plain and the natural fire cycle of the swamp. The U.S. Geological Survey has
completed the 4-year study of water level impacts downstream.
• Surface hydrology has been altered through silvacultural practices. Ditching shortens the
hydroperiod by increasing drainage rates. It also connects isolated wetlands and exposes
amphibians to threats from fish invasions.
Floods/Droughts/Natural Disasters/Climate Change
Wildland fire is a natural, frequent, and desirable occurrence in the Okefenokee habitat. However,
adjacent private industrial forestland, refuge facilities, and the growing urban interface areas create
challenges to managing natural fire. Prescribed burning is a resource and fire prevention tool used to
restore habitats and reduce the intensity of wildland fire. The landowner organization was formed to
address the management of wildfires in a more effective manner. The organization’s combined
efforts are helping to protect both refuge and private resources. The refuge must maintain the ability
to work with adjoining landowners and support the state forestry organizations through grants,
agreements, and fuels reduction burning.
Timber Management
Short rotation silviculture with heavy mechanical site preparation, including the application of
herbicides, is eliminating the habitat suitable for at-risk animals on adjoining industrial forestlands.
The refuge has begun to enter into memorandums of understanding with agreeable landowners to
grow forest products on a longer rotation. Approximately 16 percent of adjoining lands are covered
by memorandums of understanding at the present time. Land purchase and/or timber management
by the Service of critical uplands are the long-term solutions.
Industrial and Commercial Development
Demands for ground water are increasing in the coastal plain. With paper mills and other industrial
interests along the coast, the area from which they draw ground water (i.e., cone of depression)
increases and may actually be affecting the Okefenokee Swamp. Where once the ground water was
replenishing the swamp, the swamp may now be replenishing the aquifer. This would be detrimental
to the health of the swamp by creating drier conditions and the loss of wetlands, concentrating
contaminants and degrading the system.
16 Okefenokee National Wildlife Refuge
Air Pollution
The amount of substances dispersed in the atmosphere and deposited by precipitation, aerosols, and
gasses is of great concern and is expected to continue to increase throughout North America.
Okefenokee Refuge serves as a regional base for air quality by participating in two air quality
programs - The National Atmospheric Deposition Program (measuring substances introduced into
precipitation falling on the refuge) and the Interagency Monitoring of Protected Visual Environments
(measuring the substances filtered from the air). The primary purpose is to protect the visibility in this
Class 1 air shed and to characterize the regional haze. Trends related to hydrogen, major and trace
elements from sodium to lead, nitrates, chloride, organic and elemental carbon, and PM 10 size
particles are examined. Continued monitoring and implementation of industrial limits are required to
protect this air shed.
Authorized Public Use Activities
The Okefenokee Education and Research Center, in Folkston, Georgia, is now partially funded and
beginning operations that will increase environmental education use and scientific research on the
refuge. Special refuge accommodations related to facilities, staffing, budgeting, and carrying
capacities will have to be planned in advance in order to accommodate these significant increases in
activities.
In addition, public use activities will be evaluated as to their impacts on the wilderness and other
resources and modified when necessary.
Urbanization
Charlton, Ware, and Clinch Counties in Georgia, and Baker County in Florida, all touch portions of
the refuge. Homes and subdivision developments have shown a marked increase in numbers over
the past 10 years. These homes are encroaching on and further fragment the habitats around the
refuge. In addition, this development requires the withdrawal of ground water for water systems and
increases pollution of air, water, light, and noise. These developments also create significant
problems in protecting structures and fighting wildfires in the area.
LEGAL AND POLICY GUIDANCE
The administration of Okefenokee Refuge is guided not only by the refuge’s authorizing legislation
and the National Wildlife Refuge System Improvement Act of 1997, but by a variety of federal laws,
Presidential executive orders, and international treaties. For the establishing executive order and a
description of the key legislation and policies, see Appendix I.
Section A. Comprehensive Conservation Plan 17
II. Refuge Environment
PHYSICAL ENVIRONMENT
CLIMATE
The climate of Okefenokee National Wildlife Refuge is warm and humid for most of the year
(Table 1). This is due in part to its southern latitude and also to its proximity to the Atlantic Ocean
and the Gulf of Mexico.
All four seasons are apparent, though spring and fall are usually short. Winters are usually mild and
summers are long, hot, and humid. The average yearly rainfall for the swamp is 52.29 inches
(1945-2003). The maximum yearly rainfall was 78.11 inches in 1947 and the lowest rainfall total
measured was 26.07 recorded in 1954. Climatological averages show that November is normally the
driest month with 2.18 inches, and July is normally the wettest month with 7.43 inches. The average
annual maximum temperature is 93 degrees and the average annual minimum temperature
is 42 degrees.
During the summer, the weather pattern is dominated by the Bermuda High. This feature usually
extends along 35 degrees north latitude across the Atlantic Ocean and into the Gulf of Mexico. This
pattern blocks fronts from progressing into south Georgia and Florida and ushers in warm moist air
from the Atlantic Ocean and Gulf of Mexico. This flow of moist air over the warm land surfaces
creates frequent afternoon thunderstorms. Under weak atmospheric flow or stagnant conditions,
these thunderstorms are often initiated by the sea breeze front from either coast. Intense
thunderstorms producing heavy downpours of rain and frequent cloud to ground lightning strikes are
common during summer afternoons and evenings. Coincidently, most of the wildfires occur during
this period. The summer weather pattern can also be affected by tropical systems moving across the
area. Hurricanes, tropical storms, and tropical depressions moving ashore from the Atlantic Ocean or
the Gulf of Mexico can produce very heavy rain across the region. Summer high temperatures will
normally exceed 100 degrees on two or three occasions. Nighttime temperatures normally range in
the upper 60s to lower 70s.
In winter, without the blocking effect of the Bermuda High and with shorter days and less heating, cold
fronts will move through the area. Winter conditions are often controlled by large mid-latitude weather
systems in which most storm development occurs over the middle of the country or the Gulf of Mexico
and move east and southeast into the Atlantic Ocean and into Florida. As cold fronts pass through the
area, the wind shifts from the southwest to the northwest and north. After a cold frontal passage, high
pressure will dominate the area with weather conditions becoming drier and stable for a period, with
steady northerly winds, cold temperatures, and low relative humidity values. Temperatures can vary
greatly from day-to-day, with readings ranging from the seventies to the teens within a period of a few
days. During the winter, the refuge has an average high temperature of 67 degrees and an average
low of 42 degrees. A normal winter will have about 21 days below 32 degrees.
During the spring and fall, the weather can be quite variable across the region. In the fall, cold fronts
return to the south Georgia/north Florida area. In the early fall and late spring, many cold fronts will
stall and become stationary in north Florida before becoming warm fronts and moving back toward
the north. These warm fronts will bring warm moist air northward overriding the colder air and
creating cloudy, drizzly, rainy conditions. In the spring, mid-latitude weather systems intensify in the
Great Plains and sweep eastward. Cold Canadian air masses colliding with warm moist air from the
18 Okefenokee National Wildlife Refuge
Gulf of Mexico will bring thunderstorm squall lines through the area. The highest frequency of severe
weather, such as tornadoes, occurs in the spring, in large part, due to the collision of the colder, drier
air mass with the warm, moist Gulf air (McAllister 1998).
Table 1. Climatological averages at Camp Cornelia weather station (east entrance)
Average
Minimum oF
Average
Maximum oF
Absolute
Minimum oF
Absolute
Maximum oF
Rainfall
(Average)
Year 1990-2003 1990-2003 1990-2003 1990-2003 1945-2003
January 42 67 16 84 3.50
February 46 71 13 88 3.39
March 50 76 21 90 4.30
April 55 82 34 95 3.25
May 62 89 38 103 3.67
June 68 92 54 104 5.83
July 71 95 63 106 7.43
August 70 93 61 104 7.27
September 68 89 50 98 5.37
October 58 82 36 95 3.22
November 49 75 24 89 2.18
December 44 67 19 83 2.87
Relative humidity averages are fairly high due to the refuge's location between the Gulf of Mexico and
the Atlantic Ocean. Year-round averages at 7:00 a.m. are about 85 percent. Minimum relative
humidity (about 2:30 p.m.) averages about 52 percent. Maximum relative humidity reaches 100
percent every night except during the very driest of seasons.
Most dormant season prescribed burning takes place during several days of stable weather
conditions following each weather system. Although very little lightning occurs during this period, a
secondary fire season exists during the winter months. An abundance of cured understory
vegetation, occasional heavy winds, and the presence of a great deal of prescribed burning
contributes to this wildfire danger. If arson were more prevalent, the winter season might be the
major wildfire season.
During the short spring and fall seasons, normal lightning activity is only moderate; thus, wildfires
caused by lightning are not common.
From mid-May through mid-September, most storm systems are convective in nature. Warm, moist
air masses begin to rise, causing the convective thunderstorms common to this area during this
period. Spectacular lightning storms with hundreds of strikes often occur. Most wildfires occur
during this period. These late spring and summer wildfires are the major factor that shaped the
Section A. Comprehensive Conservation Plan 19
historical longleaf pine communities once common to this area and maintained the swamp’s
diversified landscape. Growing season prescribed fire is being introduced to restore these
environmental conditions. The unstable winds caused by afternoon thunderstorms may make
burning conditions very difficult. Careful planning, timing, and execution are very important.
HISTORICAL/ECOLOGICAL ROLE OF NATURAL EVENTS
Although fire is the most obvious natural event shaping the Okefenokee Ecosystem, several other
recurring events have played an important part. These events include drought, lightning strikes,
insect infestations, diseases, tornados, windstorms (microbursts), hurricanes, and water level
fluctuations.
Role of Fire in Uplands
Fire determines the overstory and ground cover species dominating the uplands within the refuge,
and indirectly, its wildlife species. The Okefenokee Ecosystem is part of the vast southeastern
coastal plain where the uplands were once dominated by a major fire-dependent plant association,
the longleaf pine community. The southeast once supported 60- to 92-million acres of this
association.
Ecologists have identified more than 30 longleaf pine associations supporting a wide array of native
wildlife species. The most traditional community association is longleaf pine/wiregrass. Longleaf
pine and wiregrass, along with many of its associated wildlife species, including the red-cockaded
woodpecker, gopher tortoise, and indigo snake are all long-lived but reproductively unprolific species.
As long as the area remained undisturbed, the community prospered. The fine, resinous, wiregrass
understory promoted the spread of frequent, low-intensity wildfires over vast areas, killing seedlings
of competing pine species as they attempted to invade the uplands from the edges of swamps,
ponds, and river bottoms. The fire resistant longleaf pine seedlings and mature pines survived, thus
perpetuating the open park-like longleaf pine community. Growing season fires, during the normal
lightning season, stimulated the seeding of new clones of wire grass and other community plants,
while setting back growth of tall shrub species, such as gallberry (Ilex coriacea), palmetto (Serenoe
repens) and hurrah bush (Lyonia lucida). The understory components and structure of longleaf pine
communities provided a diverse habitat suitable for all other native species of wildlife common to the
southeastern coastal plain.
Upland fire, in addition to perpetuating longleaf community species, created additional habitat
diversity by acting with other natural disturbances to create openings in the mature forest overstory.
Over many hundreds of years, the regular occurrence of new openings resulted in the traditional,
multi-aged longleaf pine forest. As the new openings seeded in to create new age classes, fire, in
turn, destroyed less fire resistant seedlings, maintaining the pure longleaf stand.
During pre-settlement times, fire in the longleaf pine association was quite common. Lightning
season fires were frequent and widespread. Analysis of the flammability of longleaf community
understory species, the frequency of lightning strikes, and the presence and location of natural
barriers have shown the average fire frequency on the uplands surrounding the Okefenokee Swamp
to have been one to three years (Frost 1998).
Fire ignited during all seasons by natives and early settlers for cultural reasons added to the effects of
lightning caused fire. Fire was used by native Americans to stimulate berry growth, to improve
hunting, and to clear land. Later settlers continued to set fires for similar reasons, as well as to
improve cattle grazing (Wahlenberg 1946).
20 Okefenokee National Wildlife Refuge
Role of Fire in Wetlands
Fire has played an important part in the formation of the Okefenokee Swamp. The entire floor of the
swamp is covered by a bed of peat varying from a few inches thick at the swamp’s edge to 3 to 15
feet thick in the swamp’s interior (Cohen 1984). During construction of logging trams in the swamp,
some holes over 20 feet deep were discovered (Hopkins 1947). In scrub/shrub and forested areas,
the root mat covering the surface of the peat is usually at about the average water level. Most of the
peat surface is covered with bog forest or dense scrub/shrub. Approximately 31,246 acres of the
swamp (8 percent) are open marshes or "prairies" varying in size up to several thousand acres.
Depending on water levels, the peat surface in the prairies is covered with a few inches to two or
three feet of water. Most of these prairies are believed to be the result of very severe fires, which
killed the woody plants and burned away part of the upper peat bed. Most of the prairie lakes and
ponds are the result of pockets being burned in the peat (Cypert 1972). Alligators may create small
open water areas or help to maintain existing “holes” (Pirkle 1984).
According to Cypert, a fire in 1844 was the last fire to be severe enough to have caused prairies.
Since then, there have been fires severe enough to kill timber but not severe enough to permanently
kill the woody vegetation and remove significant layers of peat. Repeated fires such as those in 1932
and 1954-55 could create prairie conditions, however. One area examined by Cypert in 1956 and
1970 was burned quite severely by both fires. Prior to 1932, another area north of the Suwannee
Canal, between Camp Cornelia and Mizell Prairie, was covered with pond cypress (Taxodium
ascendens nutans) and slash pine (Pinus elliottii). The 1932 fire killed most of the timber. By 1954, a
dense thicket of pond cypress, white bay (Magnolia virginiana), sweet bay (Persea borbonia), black
gum (Nyssa sylvatica), hurrah, titi (Cyrilla racemiflora), and bamboo vine (Smilax laurifolia) sprouted
up in its place. The 1954-55 fire burned away the remaining trees, the thicket, and about one foot of
peat. When inspected in 1956 and again in 1970, the woody growth had been reduced severely.
One more severe fire over this area would probably result in a prairie (Cypert 1973).
The swamp ponds and prairies seem to be slowly reverting to swamp forest. Cypert classified 60,000
acres as prairie during his studies following the 1954-55 fires (Cypert 1973). Cyndy Loftin’s studies
during the 1990s showed about 31,246 acres as prairie (Loftin 1998). The future occurrence of
drought periods and fires will play an extremely important role in the appearance and character of the
Okefenokee as a wildlife refuge. In a report on a 13-year study of “Plant Succession on Burned
Areas in the Okefenokee Swamp following the fires of 1954 and 1955,” Eugene Cypert (1972)
concludes the following:
"It is difficult to appraise the importance of extreme droughts and the accompanying fires to
Okefenokee Swamp. The aesthetic damage is incalculable. Doubtless the droughts and fires are
damaging to most forms of swamp wildlife at the time of their occurrence. However, the prairies and
the prairie lakes and ponds are a unique part of the swamp. It is obvious that they are now slowly but
steadily reverting to swamp forest. If this trend should continue until the whole swamp is forested,
most of the more important and interesting species of wildlife would be adversely affected. The
sandhill crane, bitterns, rails, gallinules and the roundtail muskrat would disappear entirely from the
swamp. There would be little use of the swamp by waterfowl. Alligators would probably survive but
their required habitat would be drastically reduced. Herons, ibises, ospreys and probably other
important kinds of wildlife would become rare or disappear from the swamp. Serious consideration
must be given as to what control measures should and should not be taken to prevent or to permit
fires in Okefenokee Swamp during periods of extreme drought."
Fire also plays an important role in maintaining the numerous isolated wetlands that are interspersed
throughout the uplands. Keeping fire out of these areas has promoted the growth of the woody
understory and diminished their function. Restoring these wetlands by allowing fire to pass through
Section A. Comprehensive Conservation Plan 21
them contributes to the overall health of the ecosystem by re-establishing the natural hydrology. As a
result, conditions for the reproduction of amphibians are enhanced.
Role of Other Natural Events
Lightning - Most of the fires that served to maintain upland and wetland ecosystems were started by
lightning; however, the vast majority of lightning strikes do not start fires. Lightning has the additional
important effect of maintaining age, diameter, and density diversity by killing small clumps of trees,
creating natural patch regeneration areas. Fire, in turn, destroys seedlings of any other less fire
resistant species, maintaining the pure longleaf stand. Within the swamp, lightning’s only effect,
other than igniting fires, is to kill single trees or groups of trees.
Wind Storms - The occurrence of tornados, wind storms, and microbursts is less common than
lightning but these natural events also create openings and new stands in uplands and wetlands.
The effects of hurricane force winds are more difficult to assess. The effects of past hurricanes are
very anecdotal. In addition, twentieth century hurricane seasons are believed to be very anomalous,
departing from the 18th and 19th century frequency of a particularly destructive hurricane season
every 20 years (Sandrik and Landsea 2003). Sandrik’s research has identified two hurricanes during
the 19th century that should have been very destructive to Okefenokee’s timber stands, one in
1896 (category 3) and one in 1813.
Historians indicate that longleaf pine reached ages of up to 400 years on the southeastern coastal plain.
Plantations managed for quail hunting in west Georgia contain groves of longleaf pine approaching this
age. A section cut from a stump on Blackjack Island in Okefenokee Swamp in 1920 and burned many
times since, still shows 300 growth rings (Phernetton personal communication). It is not known how
resistant longleaf pine is to category 3 hurricanes, but if each hurricane of this nature was totally
destructive to longleaf pine stands, very few trees would reach the age of
400 years. It is postulated that longleaf pine stands are at least partially resistant to hurricane winds of
up to 120 mph, although hurricanes and accompanying tornados probably played a large part in the
patchwork multi-aged stand makeup of old-growth longleaf pine stands. A study at the Medway
Plantation near Charleston, South Carolina, following Hurricane Hugo, a category 4 hurricane, supports
the resistance of longleaf pine to hurricanes. The eye of Hurricane Hugo passed within a few miles of
the plantation. A survey of damages showed 70 percent of the longleaf pine to be standing while less
than 20 percent of the loblolly pine (Pinus taeda) remained (Hortman personal communication).
There is no documented evidence of the effects of hurricanes within the wetlands, although some of
the hurricanes of the 1800s must have passed through the swamp.
Hurricanes and tropical storms indirectly affect the ecosystem by controlling fire. The summer fire
season is often terminated by a series of tropical storms that extinguish surface fires and recharge
water levels, drowning fires smoldering in the organic layers of the swamp.
Water Levels - Fluctuating water levels affect the Okefenokee wetlands in several ways. Periods of
drying and flooding affect the species composition in the wetlands. Rates of decomposition of
organic material are determined by exposure times during dry periods (Yin and Brook 1992).
22 Okefenokee National Wildlife Refuge
Water levels also play a very important factor in determining fire effects. Water levels determine:
• Whether a fire will burn at all, even on the uplands.
• Whether the fire will burn into the swamp or remain confined to uplands.The effectiveness of
natural barriers within the swamp. Natural barriers may isolate fires within sections of the swamp.
• Whether it will burn only the aerial portion of the swamp vegetation resulting in a temporary
opening until scrub/shrub or other vegetation grows from root sprouts.
• Whether it will burn into the root mat, creating permanent openings.
• Whether it will burn deep into decomposed peat, creating new lakes and prairies.
PHYSIOGRAPHY AND GEOLOGY
Okefenokee Refuge lies within the South Atlantic Coastal Plain that covers northeastern Florida, the
southern half of Georgia, and the eastern halves of South Carolina and North Carolina. This
physiographic region’s western boundary is the fall line that marks the beginning of the hilly Piedmont
and its eastern boundary is the Atlantic Ocean. As part of a continuous Coastal Plain that extends
from New York to Texas, it has arbitrary boundaries at the Alabama-Georgia border and at the North
Carolina-Virginia border, extending into the southeast corner of Virginia only to capture the very
Southeastern Great Dismal Swamp. The southeastern boundary marks a broad transitional zone into
Peninsular Florida (http://blm.gov/wildlife/pifplans.htm).
The Okefenokee Swamp is a vast peat bog filling a huge saucer-shaped sandy depression. The
upper margin of the swamp, or the "swamp line," ranges in elevation from 125 feet above sea level on
the northeast side to 105 feet on the southwest side. The shallow, dark-stained waters of the refuge
flow slowly but continuously across the swamp toward the two outlets--the famed Suwannee River on
the west side and the historic St. Marys River on the southeast. Scattered throughout the swamp are
narrow arcuate sandy ridges forming islands and peninsulas.
The origin of the Okefenokee Swamp has been a subject of continuous debate among geologists and
historians. Two theories have developed to describe the origin of the swamp (Parrish and Rykiel, Jr.
1979). The traditional and more popular (although probably incorrect) theory developed by R. M.
Harper in 1909 places the origin of the swamp prior to the Illinois glaciation period, several hundred
thousand years ago. Ocean currents are thought to have caused a series of spits (sand bars) to form
along the eastern edge of the swamp. When water levels dropped during the ensuing glaciation
period, a large body of water was trapped behind the sand bar (Trail Ridge) creating a marine lagoon.
Over a period of time, salt water was replaced by fresh water and the lake began to fill with organic
vegetation. As peat accumulated, the lake gradually turned into a swamp (Pirkle and Pirkle 1984;
Trowell 1994).
The Holocene freshwater theory postulated by O. Veatch in 1911 was expanded in recent times by
others (Parish and Rykiel 1979; Brooks 1966; Rich 1979; Davis 1987; Huddleston 1988) and
summarized by C. T. Trowell (1994). This freshwater theory indicates that origins of the Okefenokee
Swamp were much more complex than previously believed. Basically the swamp formed in two
stages. A series of events beginning during the Miocene Period through the Pleistocene Period
resulted in the formation of the Okefenokee Basin. These events include: a 200-foot thick layer of
clay deposited on the coastal plain; delta bars formed by ancient rivers; formation of a series of step
like terraces and barrier islands by fluctuating ocean levels; diversion of drainages and capturing of
rivers by geologic uplifts. These delta bars and barrier islands are present today and form the upland
habitats of the refuge. The second stage, formation of the swamp, began during very recent times
(Holocene Period) as a freshwater event (Pirkle 1984; Trowell 1994).
Section A. Comprehensive Conservation Plan 23
The Okefenokee Swamp is located on the Wicomico Terrace (Okefenokee Terrace, Sunderland
Terrace, Northern Highlands) left at an elevation of 100 to 120 feet above sea level by an earlier
receding sea level. The swamp’s eastern margin, Trail Ridge, is an ancient beach ridge created by
wave/wind action at the cresting edge of an eroding, encroaching sea during the Pliocene or
Pleistocene ages. The 200-foot thick impermeable calcareous clay layer called the Hawthorn
Formation underlies the Wicomico Terrace. The Hawthorn Formation overlays the carbonate
formation forming the Floridan Aquifer. The Hawthorn Formation bordered by Trail Ridge is a key
element in the formation of the Okefenokee Swamp (Pirkle 1984 and Pirkle and Pirkle 1984, Rich
1979, Trowell 1994) (Figure 7).
During the Wisconsin glaciation period, the swamp was high and dry with no evidence of organic
material formed by marine organisms. Oak forests and prairie probably dominated the landscape.
Fire was common. As the climate became warmer, the glaciers began to recede, the environment
became more humid, rainfall increased, and ocean levels and the groundwater table began to rise.
From about 5,000 years ago to the present, vegetation gradually changed from upland herb/oak
communities to longleaf pine forests. The thick clay bottom held water in the basin. Low areas
remained wet year-round. The Okefenokee Swamp began to form. Mesic broadleaved communities
began to form in depressions and along drainages. Cypress began to invade the swamp. The
swamp forest spread laterally away from stream courses and small lakes as peat accumulated. As
peat accumulated, raising the water table, the swamp grew vertically and laterally until it eventually
covered higher areas between streams and ponds, eventually forming the swamp as we know it
today (Parish and Rykiel 1979; Trowell 1994).
SOILS
A soil survey concentrating on the uplands of the Okefenokee Swamp was completed by the National
Resources Conservation Service in 1996. A soil profile showing the relative position of each series is
illustrated in Figure 8 and a brief description of each soil series is presented in Table 2. The soil
types are generally arranged from the lowest wetland to the highest upland.
HYDROLOGY
The Okefenokee Swamp is considered a deepwater swamp containing peat soils. It is an elevated
wetland ranging from an elevation of 125 feet above mean sea level (AMSL) on the northeast side of
the refuge to 105 feet AMSL at the outflow to the Suwannee River. Although most of the area has no
perceptible surface flow, the water is not stagnant and flows across the swamp through a series of
depressions stair-stepping towards the outlets of the swamp.
The Okefenokee Swamp receives water via precipitation (70 percent) and surface runoff (30 percent)
(Rykiel 1977). Measurement of the watershed draining directly into the swamp (30 X 60 minute
Geological Survey Map; scale-100,000, 1980) shows a drainage of 600 square miles. Over 400
square miles of the watershed are located northwest of the swamp. The remaining 200 square miles
drain a narrow strip between the swamp’s edge and Trail Ridge to the east, Waycross Ridge to the
north, and a series of islands and ridges south of the swamp through many small parallel creeks.
Major creeks draining into the swamp on the northwest side are: Black River, Alligator Creek (north),
Greasy Branch, Suwannee Creek, Cane Creek, Bear Branch, Surveyors Creek, Barnum Branch,
Turkey Branch, and Big Branch.
Groundwater contributions to the swamp’s water budget are not well known. However, some prairies
may be influenced locally by groundwater contributions (Loftin 1998). Holes in the bed of the swamp
24 Okefenokee National Wildlife Refuge
Figure 7. West to east profile of the sediments under the Okefenokee Swamp and
surrounding it (Hyatt 1984)
Figure 8. Typical soils series within the Okefenokee National Wildlife Refuge with the
associated vegetation types
Section A. Comprehensive Conservation Plan 25
were located during construction of logging railroads (Hopkins 1947). There is a possibility of
sinkholes in the bed of the swamp, which may allow seepage through the Hawthorn formation to or
from the aquifers below. Most available studies, however, indicate that the Hawthorn formation
effectively separates the water table aquifer from the principal artesian aquifer (Rykiel 1977). The
swamp may receive some input from surficial aquifers. Researchers have detected cold water
currents in some locations (Loftin 1998).Rykiel determined that in general 80 percent of the water
output from the swamp left through evapotranspiration and only 20 percent left via river and stream
flow. The principal drainages are the Suwannee River (85 percent of the surface water outflow), the
St. Marys River (11 percent), and Cypress Creek (4 percent). The northern four-fifths of the swamp
drain into the Suwannee River. The St. Marys River drains only the area east and south of Blackjack
Island, south of Mitchell and Broomstraw Islands, and areas surrounding Soldier Camp Island.
Loftin (1998) defined five major hydrologic “basins” within the swamp (Figure 9). Although they are
partially connected and demonstrate similar seasonal trends, the amplitudes of these trends vary
regionally. The northwestern region, including the Suwannee River, experiences the greatest seasonal
and annual fluctuations in water elevations. Over a 3- to 4-week period, water elevations may fluctuate
+0.75 m. This corresponds to seasonal rainfall, not only that which falls over the swamp, but also that
falling on the area northwest of the swamp and carried into the region by numerous streams. The least
water level fluctuations occur in the northeast region of the swamp where during the same interval,
elevations might fluctuate <+0.06 m. This may be because less runoff is received from neighboring
uplands or there is a contribution of ground water in the area. Vegetation composition differs between
these areas, which may also affect regional evaporative demands. Surface outflow is also more limited
from the northeast basin than from the northwest basin.
The water level varies from 117.6 feet in dry years to 123 feet in wet years on the east side and from
110.4 feet to 118.6 feet on the west side. Average water level at Camp Cornelia is 121.4 feet and at
Jones Island is 115.2 feet. Table 3 shows semi-monthly average water levels at Suwannee Canal
and Stephen C. Foster State Park.
The swamp has experienced extreme highs and lows throughout history. Droughts have been
reported in the literature and summarized by Rykiel (1977) during the following years: 1844, 1856-57
(winter), 1860, 1902, 1909-10, 1932, 1943, 1954-55. During some of these droughts, the Suwannee
River and Billys Lake were dry (1860 and 1943). Precipitation during 1954 was 26.07 inches. Since
this time, annual rainfall has not been below 33 inches. The eastern side of the refuge received less
than 40 inches of rain in 1968, 1978, 1981, and 1990. Annual precipitation was over 70 inches during
1948, 1964, 1973, and 1991.
A 5-mile earthen dike and two water control structures were completed in 1960 to reduce the flow of
water out of the swamp during drought periods. This structure was examined through an
environmental assessment (U.S. Fish and Wildlife Service 1998). The assessment recommends that
the sill should be breached and the water control structures removed to re-connect the swamp with
the Suwannee River.
Isolated Wetlands
Seasonally ponded isolated wetlands are scattered over the uplands of the Okefenokee Ecosystem in
association with sandy soils. Dependent on rainfall and adjacent run-off, water levels fluctuate in these
shallow basins causing cycles of drying and wetting. Unless altered, they are not connected to other
wetlands, are not spring-fed, and lack a permanent fish population. Within the refuge, these ponds
begin filling as the fall rains come. By June, most small ponds are again dry. This cycle along the
edges of the ponds is critical for the successful reproduction of amphibian and invertebrate species.
26 Okefenokee National Wildlife Refuge
Figure 9. Hydrological basins within the Okefenokee Swamp (Loftin 1998)
Section A. Comprehensive Conservation Plan 27
Table 2. Soil series descriptions at Okefenokee National Wildlife Refuge
2 COMPOSITION
NAME
1 MAP
SYMBOL
S C OM
3 SITE INDEX
4 WATER
TABLE
DEPTH (ft)
FLOODED PERMEABILITY REMARKS
DASHER
MUCK
728A1 R% 0% 40-99% PP: Varies
CYP: Varies
+? to -0.5 Usually Moderately rapid Identifying characteristic: OM extends > 51
inches.
Assoc. Veg.: Scrub pond & slash pine;
cypress; water tupelo;swamp tupelo; sweet
bay magnolia.
Ground Cover: Saw grass; iris; bull-tongue;
arrowhead; greenbriar; ferns; aquatic plants.
CROATAN 28A1 R% 0% 25-60% Scrb Pines:Varies
Cypress: Varies
+? to -1.0 Seasonally Rapid Identifying characteristic: OM extends to 28
inches.
Location: Depressions; Between Dasher &
upland.
Ground Cover: Saw grass; iris; bull-tongue;
arrowhead; greenbriar; ferns; aquatic plants.
KINSTON/
JOHNSTON
767A1 R% 5-18% 2-8% BHwds: 90-100
Loblolly P: 100
0 to -1.0 Common Moderate to
Rapid
Location : Flood Plains. Rare on Okefenokee
NWR except on Suwannee River drainage.
ALLANTON
MUCK SAND
(ponded)
855A1 R% 3-12% 10-20% Cypress: 75
Wet Hwds: NA
Seasonally Moderate to
Moderately
Rapid
Location: Depressions; Ponds
Identifying Characteristic: Organic stained
layers to 80 in.
Assoc. Veg.:Red maple; swamp & water
tupelo; swamp chestnut oak; water oak; willow
oak; cypress; sweetgum.
Understory: Greenbrial; hurrah bush; titi;
other shrubs.
SURRENCY
MUCKY SAND
(ponded)
55A1 R% 2-8% 10-20% Sweetgum: 90
Slash P: 90
Loblolly P: 95
Misc Hwds: varies
Cypress: varies
0 to -0.5 Common Moderate Location: Drainage ways & depressions.
Assoc. Veg.: Hardwood forest types; pond
pine; slash pine; Lob. Pine.
Understory: Greenbriar; hurrah bush; titi; other
wetland shrubs.
28 Okenokee National Wildlife Refuge
2 COMPOSITION
NAME
1 MAP
SYMBOL
S C OM
3 SITE INDEX
4 WATER
TABLE
DEPTH (ft)
FLOODED PERMEABILITY REMARKS
MASCOTTE
MUCKY FINE
SAND
840A1 R% 0-5% 2-7% Longleaf P.:
Slash P.: NA
Loblolly P.: NA
+1.0 to -
1.0
Moderately Slow Characteristics: Very deep, very poorly
drained. Marine deposits.
Location: Level, flatwood areas, depressions
and low stream terraces.
Assoc Veg: Longleaf, slash, & loblolly pines.
Understory: Palmetto, gallberry, fetterbush,
myrtle, grasses.
LEON SAND
(ponded)
39A1 R% 1-6% 10-20% Slash pine: 75
Loblolly pine: 70
+2 to -3.5 Common Moderate to
Rapid
Location: Outside ring of many islands in Oke
Swamp.
Assoc. Veg.: Probably slash & loblolly pine.
Understory: Heavy rough; gallberry; hurrah
bush; poor mans soap.
RUTLEGE
SAND
(ponded)
755A1 R% 2-10% 3-9% Cypress: 75
Other Hwds: NA
0 to -1.0 Common Rapid Location: Shallow depressions and
drainageways. In Oke, located in shallow
areas between islands or drainages between
upland areas.
Assoc Veg.: Hardwoods forest; pond, slash,
loblolly pines.
Understory: Gallberry; huckleberry; myrtle;
grasses; sedges.
MASCOTTE
FINE SAND
740A1 R% 0-5% 2-7% Longleaf P: 70
Slash P: 85
Loblolly P: 80
0 to -1.0 Moderately Slow Location: Broad low-lying areas. Examples are
east end of Seldom Seen Point and high part
of Comp 9-3.
Characteristics: Loamy; Depth of 24 - 40
inches.
Assoc. Veg.on Higher areas: Longleaf & slash
pine.
Understory: Gallberry; palmetto; myrtle; hurrah
bush; grasses.
Assoc. Veg. on Depressional areas: Slash P;
Cypress; Wetland hardwoods.
Understory: Grasses; ferns; moss; pitcher
plants, greenbriar; sedges.
Section A. Comprehensive Conservation Plan 29
2 COMPOSITION
NAME
1 MAP
SYMBOL
S C OM
3 SITE INDEX
4 WATER
TABLE
DEPTH (ft)
FLOODED PERMEABILITY REMARKS
PELHAM
LOAMY SAND
(ponded)
52A1 R% 1-8% 1-2% Wet Hwds: 86
Slash P.: 86
Loblolly P: 86
-0.5 to -1.5 Subject to
Flooding
Seasonally
Ponded
Moderate Characteristic: Deep, poorly drained.
Location: Low flats, depressions.
Drainageways, ponds.
Assoc. Veg.: Slash, loblolly, pond P.;
sweetgum; blackgum, swamp tupelo, water
oak, cypress.
Understory: Gallberry, myrtle, other water
tollerant veg.
SAPELO FINE
SAND
(moderately
wet)
65A1 R% 2-5% 1-3% Longleaf P.: 65
Slash P.: 85
Loblolly P.: 85
-0.5 to -1.5 Moderate Characteristic: Deep, poorly drained, sandy
throughout.
Location: Low pine flatwood areas adjacent to
depress-ions and drainageways.
Assoc. Veg.: Longleaf, slash, loblolly pines.
Understory:
PELHAM
LOAMY SAND
752A1 R% 5-10% 1-2% Sweetgum: 80
Blackgum: 80
Water oak: 80
Longleaf P.: 80
Slash P.: 90
Loblolly P.: 90
-0.5 to -1.5 Subject to
Flooding.
Moderate Characteristics: Deep, poorly drained. Subsoil
is loamy, extends to depths greater than 5 ft.
Well suited to forest management.
Location: Low flats, depressions and
drainageways. Examples are found in the
Suwannee River drainage.
Assoc. Veg.: Longleaf, slash, loblolly pines;
sweetgum; blackgum ; water oak; cypress.
Understory: Gallberry, myrtle, palmetto,
swamp holly, wire grass and other water
tollerant grasses.
SAPELO FINE
SAND
765A1 R% 2-5% 1-3% Longleaf p.: 65
Slash P.: 77
Loblolly P.: 77
-0.5 to -1.5 Moderate Characteristics: Deep, poorly drained, sand
throughout.
Location: Flatwood areas adjacent to
depressions and drainageways. Examples are
flatwood parts of peninsulas extending into the
swamp (C 11-4, C 12, parts of C 8, Strange
Island).
Assoc. Veg.: Longleaf, slash, loblolly P.;
blackgum; water oak.
Understory: Gallberry, palmetto, dwarf
huckleberry.
30 Okenokee National Wildlife Refuge
2 COMPOSITION
NAME
1 MAP
SYMBOL
S C OM
3 SITE INDEX
4 WATER
TABLE
DEPTH (ft)
FLOODED PERMEABILITY REMARKS
LEON SAND 739A1 R% 1-5% O.5-4% Longleaf P.: 70
Slash P.: 80
Loblolly P.: 75
0 to -1 ft. Moderate
to
Moderately rapid
Characteristics: Deep, poorly drained soil.
Sandy with organic stained layers below 15
inches.
Location: Smooth uplands. Mid-level parts of
most islands in swamp.
Assoc. Veg.: Longleaf and other pines; water
oak.
Understory: Myrtle, palmetto, gallberry.
PLUMMER 751A1 R% 1-10% 1-3% Longleaf P.: 70
Slash P.: 88
Loblolly P.: 91
0 to -1.0 Subject
to
Flooding
Moderately
Rapid
Characteristics: Deep, poorly drained soil.
Subloil loamy down to 5 ft.
Location: Low flats, depressions and
drainageways.
Assoc. Veg.: Longleaf, slash and loblolly pine;
swamp tupelo; cypress.
Understory: Gallberry; waxmyrtle; bayberry;
wiregrass; pitcher plants; bracken fern.
LYNN HAVEN
SAND
808A1 R% 1-6% 1-4% Longleaf P.: 70
Pond P.: 70
Slash P.: 85
Loblolly P. 80
0.0 tp 0.5
wet
periods
>-3.5
dry periods
None Moderate
to
Moderately
Rapid
Characteristics: Very deep, very poorly
drained sandy soil. Location: Low level
flatwoods and depressions. Chesser Island
near homestead.
Assoc. Veg.: Longleaf and slash pines.
Underatory: Palmetto, gallberry, fetterbush,
huckberry, grasses.
MANDARAN
SAND
19A1 R% 0-3% 0.5-3% Longleaf P.: 60
Slash P.: 70
Live Oak: NA
Moderate Characteristics: Somewhat poorly drained soil,
thick sandy deposit on marine terraces.
Location: Found on Trail Ridge and ridge of
many islands. Topped by Ridgeland sand on
highest islands.
Assoc. Veg. Longleaf and slash P.; scrub
oak.
Understory: Gallberry, palmetto, greenbriar,
grasses.
Section A. Comprehensive Conservation Plan 31
2 COMPOSITION
NAME
1 MAP
SYMBOL
S C OM
3 SITE INDEX
4 WATER
TABLE
DEPTH (ft)
FLOODED PERMEABILITY REMARKS
RIDGELAND
SAND
48A1 R% 0-10% 1-4% Longleaf P.: 70
Slash P.: 80
Loblolly P.: 80
1.5 to 2.5 Moderate
to
Moderately Rapid
Characteristics: Somewhat poorly drained soil,
very deep and sandy throughout.
Location: Ridgeline of highest islands.
Assoc. Veg.:
Understory:
CENTENNARY
SAND
81A1 R% 1-8% 0.5-1% Longleaf P.: 70
Slash P.: 85
Loblolly P.: 85
3.5 to 5.0 None Moderately Rapid Characteristics: Well drained on broad ridges
and flats.
Location: Homestead Area on Chesser Island.
Assoc. Veg: Slash and Loblolly Pine
Understory:
1The soil series designation (855A1) is printed on each map where the type exists. These series are also color coded.
2Composition: S= Sand
C= Clay
OM= Organic Material
R= Percent of clay and organic material is given. R designates the remainder is sand.
3Site Index: The site index is the height in feet a particular species will grow on a soil type in 50 years.
4Water Table Depth: Seasonal high water table.
+ Indicates above the surface.
- Indicates below the surface.
32 Okefenokee National Wildlife Refuge
Table 3. Semi-monthly average water levels (msl) at Suwannee Canal Recreation Area (SCRA)
and Stephen C. Foster State Park (SCFSP) between 1990 and 2003
Date SCRA SCFSP
Jan 1
15
119.89
120.02
114.54
114.72
Feb 1
15
120.25
120.25
115.06
115.20
Mar 1
15
120.26
120.37
115.33
115.38
Apr 1
15
120.36
120.24
115.18
114.81
May 1
15
120.08
119.81
114.44
114.03
Jun 1
15
119.57
119.62
113.86
114.02
Jul 1
15
119.57
119.62
114.10
114.16
Aug 1
15
119.82
119.94
114.31
114.42
Sep 1
15
119.91
119.85
114.34
114.42
Oct 1
15
119.94
120.11
114.28
114.56
Nov 1
15
120.11
119.96
114.45
114.39
Dec 1
15
119.86
119.86
114.33
114.39
The Suwannee River
The Suwannee River is the primary surface water outflow from the Okefenokee Swamp. Eighty-five
percent of the surface water outflow exits the swamp via this river (Rykiel 1977). From the swamp, it
travels approximately 235 miles to the Gulf of Mexico (Save Our Suwannee, Inc., brochure). Twenty-nine
miles are located in Georgia, while the remaining two-hundred and six miles are in Florida. The
Alapaha, Withlacoochee, and Santa Fe Rivers are the principal tributaries. Contributions to the river
below the sill before reaching Fargo, 12 miles downstream, include Bay Creek, Alligator Creek,
Sweetwater Creek and Jones Creek. Except for Jones Creek, the remaining creeks draw water from
the Okefenokee Swamp. Cypress Creek also draws water from the southwest corner of the swamp
and joins the river below Fargo. Loftin (1998) estimates that 10-30 percent of the water that passes
the Fargo water gauge is comprised of water passing through and around the sill. Bay, Alligator,
Sweetwater, and Jones Creeks contribute the remainder.
The Upper Suwannee River, from the swamp to White Springs, is characterized by steep banks, swift
flow, shoals, and tannic acid stained waters (Save Our Suwannee, Inc., brochure). There is evidence
along the banks that the flow in this region has cut through the Hawthorn clay and runs along the
limestone aquifer. The river channel at the Suwannee River Sill structures is at 105 feet AMSL.
Section A. Comprehensive Conservation Plan 33
Twelve miles downstream, at the Fargo gaging station, the elevation is at 91.9 feet AMSL (a 13.1-foot
drop in elevation or 1.09 feet/mile). Benton gaging station is 27 miles below Fargo at an approximate
elevation of 74.1 feet AMSL (a 17.8-foot drop in elevation or 0.66 feet/mile). Twenty-five miles further
downstream at White Springs gaging station the elevation is 48.54 feet AMSL (a 25.56-foot drop in
elevation or 1.02 feet/mile). The surrounding land use in the upper portion of the Suwannee River is
primarily timber production and sparsely populated.
Humans have influenced the Suwannee River drainage through the years, beginning with extensive
logging and turpentining by the earliest settlers. Later, mining of phosphate along the Suwannee
River banks, increasing development that eliminates flood-controlling wetlands, and discharging
effluent from towns, individual residences, and businesses have affected the river and its watershed.
WATER QUALITY
The slow-moving waters of the Okefenokee Swamp are tea-colored due to the tannic acid released
from decaying vegetation. Levels of pH have been recorded through various studies and most
recently during visits to water recorders throughout the swamp. Between 1994-1996, pH levels have
ranged between 3.36 and 4.63 within the swamp. Researchers have found pH values between 3.1
and 4.86 (Bosserman 1984). Certain plants influence the acidic levels within the swamp and cause
local variation in acidity. Winger (1997) found a mean pH level of 3.91 in the surface water within the
Narrows. With such low pH levels, Rykiel (1977) expressed the importance of rainfall and
atmospheric deposition over the Okefenokee Swamp in the mineral cycling and nutrient availability
within the system.
Examining pH levels recorded at the Fargo, Georgia, gaging station on the Suwannee River, Holder
(personal communication) found a decreasing trend in pH from 4.32 (1968) to 3.93 (1994). Mills (1994)
found the average pH of the Suwannee River just below the sill to be 3.94 with a range of 3.8 to 4.53.
Dissolved oxygen is also a factor in slow-moving water and areas of high decomposition of plant
material. Low oxygen levels are a problem to aquatic life in the Upper Suwannee River during low
water periods (Soulak personal communication) as they are assumed to be within shallow marsh
areas of the swamp.
Mercury contamination has been a Suwannee River watershed problem for at least the last 20 years
(Kasbohm 1996). A limited consumption advisory has been placed on the Suwannee River, as well
as the Okefenokee Swamp. Past investigations within the Okefenokee Swamp found a mean
mercury concentration of 0.359+0.21 mg/L (wet weight) in four species of fish. There were no
significant differences within species, among species or between years, but sample size was small
(Masson and Bowers 1995). Mercury is a natural occurring element of peat systems; however,
Winger (1997) found elevated levels in the water, sediment, and biotic communities within the
swamp. Mercury concentrations in rainfall were sufficiently high to account for these elevated levels.
Like mercury, lead is more soluble and bioavailable to aquatic biota under low pH conditions. Lead
has been studied within the fisheries and sediments of the Okefenokee Swamp. The mean wet
weight lead concentrations in 35 fish fillets was 0.505+0.51 mg/L with no differences within species,
among species, or between years (Masson and Bowers 1995). Mean lead level within the sediment
of the Narrows was reported to be 180.25 ug/g (Winger 1997).
Both mercury and lead are able to bioaccummulate through the Okefenokee system possibly
affecting reproduction, hormone levels, and behavior of the fauna.
34 Okefenokee National Wildlife Refuge
AIR QUALITY
The Clean Air Act’s Prevention of Significant Deterioration (PSD) program was established, in part,
“to preserve, protect and enhance the air quality in national parks, national monuments, national
seashores, and other areas of special national or regional natural, recreational, scenic or historic
value,” including wilderness areas. Under this PSD program, certain areas of the country were set
aside to receive the most stringent degree of air quality protection. These so-called “Class I” areas
include:
• International parks;
• National wilderness areas and national memorial parks in excess of 5,000 acres; and
• National parks in excess of 6,000 acres.
The Okefenokee Wilderness is one of the 21 Class I areas administered by the Fish and Wildlife
Service. It is a member of the Southeast States Air Resource Managers regional planning
partnership. The Service has the responsibility to protect the air quality and air quality related values
(AQRVs) of the area from manmade air pollution. AQRVs include vegetation, wildlife, soils, water
quality, visibility, odor, and cultural and archaeological resources. As industry and development
move into the area, the airshed and wilderness are threatened. As in most of the eastern United
States, visibility in the wilderness area is affected by pollution-caused regional haze. Rainfall,
carrying pollutants and contaminants, is the primary source of water to the swamp. It is often acidic
and may carry elevated levels of mercury that is then deposited on the refuge. As a result, some
species of fish and wildlife have elevated concentrations of mercury in their tissues. Management of
prescribed fires and wildfires in the area also affects the quality of the air. The Service monitors air
quality in the refuge in partnership with three national programs. Atmospheric pollutants in rain are
analyzed as part of the National Atmospheric Deposition Program (NADP - the “acid rain” program).
Mercury in rain is analyzed as part of the nationwide Mercury Deposition Network (MDN). And, fine
particles responsible for visibility impairment are measured as part of the Interagency Monitoring of
Protected Visual Environments (IMPROVE) program. Table 4 lists the parameters monitored at the
refuge over the past 12 years.
National Atmospheric Deposition Program
The amount of substances dispersed in the atmosphere and deposited by precipitation, aerosols, and
gasses is of great concern and is expected to continue to increase throughout North America. In
order to know the extent to which these substances are affecting agricultural, forest, and wetland
ecosystems now and in the future, it is essential that careful and standardized sampling take place
over the North American continent. It is also necessary to know how these substances are
transported from sources throughout the continent. The NADP helps scientists to monitor how
human activities and the forces of nature affect the health of the atmosphere.
National Trends Network (NTN)
The NTN was developed to gain a better understanding of the geographical distribution of acid
precipitation over time. Okefenokee Refuge is one of more than 220 sites that measure national
trends data. Weekly precipitation samples are analyzed for pH, conductivity, calcium, magnesium,
potassium, sodium, ammonium, nitrate, chloride, sulfate, and orthophosphate.
Mercury Deposition Network (MDN)
The MDN collects data from 40 sites each week. These data enable researchers to determine
seasonal and annual changes in mercury in precipitation falling on lakes, wetlands, streams, forested
watersheds, and other sensitive ecosystems.
Section A. Comprehensive Conservation Plan 35
Table 4. Air monitoring history at Okefenokee National Wildlife Refuge
Okefenokee National Wildlife Refuge - Site No. 01
Latitude: 30 44 25 N Longitude: 82 7 43 W
Elevation: 47 m Operating Agency: USFWS
Parameter Start End Years
35MM Camera Slide 04/20/1992 11/13/1992 0.6
Scattering coefficient 02/12/1993 06/01/1997 4.3
Dry/Wet Bucket 06/03/1997 Present 6.6
Dry/wet bucket plus mercury 07/29/1997 Present 6.5
IMPROVE Sampler Module A 09/28/1991 05/01/2000 8.6
IMPROVE Sampler Module A - ver 2 05/01/2000 Present 3.7
IMPROVE Sampler Module B 09/28/1991 05/01/2000 8.6
IMPROVE Sampler Module B - ver 2 05/01/2000 Present 3.7
IMPROVE Sampler Module C 09/28/1991 05/01/2000 8.6
IMPROVE Sampler Module C - ver 2 05/01/2000 Present 3.7
IMPROVE Sampler Module D 09/28/1991 05/01/2000 8.6
IMPROVE Sampler Module D - ver 2 05/01/2000 Present 3.7
Relative Humidity 02/12/1993 06/01/1997 4.3
Sulfur Dioxide 04/01/1993 02/15/1997 3.9
Ambient Temperature (aspirated) 02/12/1993 06/01/1997 4.3
Interagency Monitoring of Protected Visual Environments (IMPROVE)
One of 145 IMPROVE sites is located on Okefenokee Refuge. IMPROVE is a cooperative visibility
monitoring effort between the U.S. Environmental Protection Agency, federal land management
agencies, and state agencies. Its primary purpose is the protection of visibility in Class I areas and
the characterization of regional haze.
The IMPROVE sampler collects four simultaneous samples every three days. Trends related to
hydrogen, major and trace elements from sodium to lead, nitrates, chloride, organic and elemental
carbon, and PM10 size particles are examined.
36 Okefenokee National Wildlife Refuge
BIOLOGICAL ENVIRONMENT
FLORA
Extensive logging at the turn of the century altered the forested vegetation communities. It created
large areas suitable for shrub growth. These areas burned frequently during the early 20th century,
possibly due to the accumulation of logging debris (Loftin 1998). However, fires over the past 150
years have not been severe enough to change large areas of forests or shrub to prairies or lakes.
Wildfires between 1952 and 1977 resulted in shrub, shrub-prairie, scrub/shrub, and wet forests
becoming established in the burned areas. General observations by those familiar with the swamp
have described the encroachment of shrubs into the prairies, reducing the amount of open areas and
giving the image of the swamp filling in. Loftin (1998) found that the landscape structure of the
swamp has not changed today from what was present 150 years ago. However, there have been
shorter intervals when changes in species and structure have occurred and influenced the system.
Proportions of wet forest, shrub, and upland forest associations are approaching pre-logged
conditions, although there have been changes in the species composition within these communities.
Species composition may affect evapotranspiration and flow rates, wildlife use, and fire occurrence
and behavior. Logging and fire have a role in shaping the vegetation composition, distribution, and
structure within the swamp. Most fires have probably only reduced the litter component of the habitat,
or caused short-term changes in system structure. However, fire suppression may have caused
greater changes within the wetlands and uplands as more woody plant species became established.
Wetland Vegetation Classification
Several vegetation classifications have been used to describe Okefenokee’s swamp interior.
Wetland forest types are described in the Society of American Foresters (SAF) publication, Forest
Cover Types of North America (Eyre 1980). Hamilton (1982) described the entire range of wetland
vegetative types from mature cypress to marsh and open water. Loftin (1998) developed a 21-class
system. Loftin’s vegetation map created from 1990 satellite images is presented in Figure 10. This
classification has been used to create a 6-class habitat map (Figure 11) for basic management
purposes and a fuel model map (Figure 12) for managing fires.
Appendix III presents Loftin’s 6- and 21-classification and compares it to Hamiliton’s classes and SAF
types.
Following are descriptions of Loftin’s wetland classifications shown on the six-class vegetation cover
type map. Included are five wetland descriptions. Loftin’s sixth classification is upland forest.
Broadleaved Hardwoods - These are mature, evergreen and deciduous, broadleaved forests. Crown
density is usually great enough to limit understory vegetation, leaving the understory relatively open.
This type covers a large portion of the northwest side of the swamp. Much of this area once was
mature cypress before logging occurred in the early 20th century. Blackgum is found as sprout
growth in areas where logging removed both cypress and blackgum, and as mature blackgum forests
where only cypress was removed. Dominant species also include loblolly bay (Gordonia lasianthus),
red bay (Persea borbonia), sweet bay, largeleaf gallberry, and dahoon holly (Ilex cassine). Small
patches of shrub are commonly mixed with the bay. Scattered cypress and pine may compose less
than 20 percent of the canopy. Sphagnum moss (Sphagnum spp.) is common as ground cover
(Hamilton 1982). Because of the lack of understory vegetation, fire does not readily enter these
stands except during extreme dry periods. Little is understood about the value of broadleaved forest
Section A. Comprehensive Conservation Plan 37
Figure 10. Vegetation cover types of the Okefenokee National Wildlife Refuge (Loftin 1998)
38 Okefenokee National Wildlife Refuge
Figure 11. Six-class vegetation cover type for Okefenokee National Wildlife Refuge
Section A. Comprehensive Conservation Plan 39
Figure 12. Fuel model map for the Okefenokee National Wildlife Refuge
40 Okefenokee National Wildlife Refuge
in the Okefenokee Swamp. Current research indicates that this habitat, especially blackgum, is
valuable habitat for bear. Use of this habitat by neotropical migratory birds has not been investigated.
The stands may also harbor rare or endangered plants.
Cypress/Hardwoods (Mature) - Pond cypress occurs in the swamp as scattered individuals, small
patches interspersed with other vegetation, and as large stands. Small “virgin” stands of cypress still
exist in the north central part of the swamp and southeast part where volumes did not make
harvesting economical. The subcanopy is often dominated by broad-leaved evergreen species and
the understory by scrub/shrub species. Sphagnum moss also commonly occurs in this habitat
(Hamilton 1982). Schlesinger (1978) found this habitat to have low nutrient availability and large peat
accumulations. Other swamp species were kept in check by recurrent understory fires. Fire
frequency and intensity also determines stand densities. Most of the cypress biomass is in the tree
boles rather than in the foliage. Where the canopy is closed, this vegetative type may exhibit some of
the same habitat characteristics found in the broadleaved hardwoods type.
Mixed wetland Pine - The mixed wetland pine complex contains a canopy of at least 30 percent pine
mixed with two or more other vegetation types. Cypress, bay, scrub/shrub and prairie may be
present in various proportions (Hamilton 1982). Although slash pine grows throughout the swamp,
the most dense stands grow where the bog is shallow, such as along the swamp’s edge or above
sand ridges on the swamp’s bottom. Fire often kills the pine component where the understory allows
severe fire behavior. In other areas, where fire intensity is low, ferns develop below the pine stands
and fire will maintain a wetland savanna. Associated species are blackgum, loblolly bay, sweet bay,
pond cypress, and ferns.
Scrub/Shrub - The scrub/shrub type includes many species of evergreen and deciduous shrubs as
well as dense even-aged stands of small trees (scrub). In addition, several species of greenbriar
(Smilax sp.) often cover everything. This evergreen vine is often so dense it masks the deciduous
shrubs, making the mass appear to be evergreen. No differentiation is shown between most of the
scrub/shrub types because they appear similar on infra-red photography. Evergreen shrubs include:
hurrah bush, dahoon holly, largeleaf gallberry, and gallberry. Deciduous shrubs include: titi, common
buttonbush (Cephalanthus occidentalis), poor man’s soap (Clethra alnifolia), Virginia sweetspire (Itea
virginica), fetterbush (Leucothoe racemosa), and highbush blueberry (Vaccinium fuscatum). Scrub
species (small trees) include: young cypress, blackgum, and bay trees (Hamilton 1982). Small
patches of scattered pine, cypress, or hardwood trees may be present in the scrub/shrub. It is
interesting to speculate in the case of this scattered overstory, which way succession may be
progressing. In the absence of fire, the scrub or young tree component of the understory may grow,
joining the scattered overstory crown, shading out the remainder of the understory, eventually
developing a bog forest; or the dense understory of shrubs may prevent regeneration of the overstory
component. Fire may kill the scattered overstory, allowing the understory to dominate. It is important
to note that the scrub component of the understory may be stunted, slowly growing trees that will
permanently remain part of the understory or they may be vigorous young trees that will eventually
become overstory. The scrub/shrub vegetative type also contains small patches of prairie.
Prairie - Shallow marshes of the Okefenokee Swamp are locally called "prairies." Although this term
is incorrect in a phytogeographical sense, this long-standing term is found in earlier literature on the
swamp (Wright and Wright 1932; Hopkins 1947; Cypert 1961) and is used on U.S. Geological Survey
topographical maps. Many of these prairies contain small islands of trees, shrubs, or herbaceous
vegetation, commonly referred to as "tree houses" or "batteries." These islands cover less than 50
percent of this mapping unit. Two types of prairie are recognized: aquatic macrophyte prairie and
herbaceous prairie.
Section A. Comprehensive Conservation Plan 41
The aquatic macrophyte prairie contains the following species: Water lily (Nymphaea odorata),
spatterdock (Nuphar lutea), and floating heart (Nymphoides aquatica). Several herbaceous
emergents, pickerel weed (Pontederia cordata), golden club (Orontium aquaticum), wampee
(Peltandria virginica), pipewort (Eriocaulon compressum), and yellow-eyed grass (Xyris smalliana)
are also common. Masses of bladderwort (Utricularia spp.) and green algae are abundant
submergents. Sphagnum moss occurs in shallow areas.
The herbaceous prairie is dominated by emergents such as sedges. Other taxa often found in
herbaceous prairies include: Chain fern (Woodwardia virginica); pitcher plants (Sarricenia spp.);
swamp loosestrife (Decodon verticillatus); paint root (Lacnanthes tinctoria); wampee; golden club;
water lily; pipewort; and yellow-eyed grass. Less than 10 percent of the area is open water.
Open Water - Most or all of the lakes in the swamp occur where natural depressions in the
topography exist or where the peat has been burned out by fires in the past. There is some
speculation that some of the lakes may have been formed by subsidence of the bed of the swamp
(e.g., sink holes) but this has not been substantiated. Prairie species and eventually scrub/shrub
species gradually invade many of Okefenokee's lakes. Other open water areas are the watercourses
through the swamp. These watercourses are kept open by the flowing action of the water and by
mechanical means.
Upland Classification
Upland vegetation communities at Okefenokee Refuge have been described by Phernetton (2001)
and relate to the Society of American Foresters (SAF) standard forest cover types. Understory
species are mentioned but a more in depth discussion on understory/groundcover species follows the
type descriptions.
Upland Hardwoods - This forest cover type consists of a mixture of scrub oaks listed in the
description of SAF Type 72. The type is common throughout the Southeastern Coastal Plain,
especially in the sand hills, or dry, sandy ridges (Eyre 1980). On the refuge, this type is found on dry,
infertile, well-drained soils on almost imperceptible rises known locally as oak hammocks
(hummocks). Some of these stands were once longleaf pine stands with scrub oak in the understory.
In other cases, the soil type supports very little combustible fine fuels, allowing only low intensity fires
to pass. With the exclusion of high-intensity fire, these stands pass through successional stages to
scrub oak. These species have adapted to drought conditions, are shade tolerant, and once
established are self perpetuating if fire is excluded. Generally the oak leaf litter layer developed is
relatively fire resistant and other ground vegetation species are patchy. Where large enough to
constitute a stand, these areas are shown on refuge habitat maps as upland hardwoods. Smaller
patches of oaks usually are included in longleaf pine stands.
Longleaf Pine - Upland forest stands identified as pure longleaf pine on habitat management maps
have a basal area comprised of at least 70 percent longleaf pine Some stands on the northwest side
of the refuge have been maintained in pure condition by periodic fire ignited by cattlemen as late as
the 1940s. Some of the refuge’s pure longleaf stands are dry and infertile and will not support other
pine species (i.e., Camp Cornelia area). In the Okefenokee area, slash pine, loblolly pine, and pond
pine (Pinus serotina) are often located around the stands next to drains and ponds. Where frequent
fire has occurred, longleaf pine stands may extend to the edge of the swamp with the other pines
restricted to the very edge of the stand. Longleaf pine stands on the refuge most closely match SAF
Type 70. Principal hardwoods associated include several scrub oak species, black gum, persimmon
(Diospyros virginiana), and sweetgum (Liquidambar styraciflua). Several of the longleaf pine
community understory types are located in these stands. Ground cover density and species vary
considerably depending upon fire history and soil conditions (Eyre 1980). Understory species in this
42 Okefenokee National Wildlife Refuge
type have been drastically altered by changes in the fire regime. Some areas support dense
southern rough communities; others, where fire has occurred frequently, support variations of low
shrub/wire grass communities.
Longleaf/Mixed Pine - Pine stands are identified as longleaf/mixed pine if the longleaf basal area is
between 35 and 70 percent. This type is designated on refuge habitat management maps as
longleaf/mixed pine (LP/MP). Slash, loblolly, or pond pine may comprise the mixed pine component.
In LP/MP stands, longleaf restoration goals may be accomplished by favoring existing longleaf pine
during selective thinning operations. Where associated with slash pine, the stand fits the description
of SAF Type 83. This type occurs on a variety of sites since the range of all of the pine species is
from dry sandy ridges to poorly drained flatwoods. Longleaf/mixed pine stands occur most often
where fire is excluded and a slash pine seed source is present. With or without fire, this type is
temporary. Burning destroys regeneration of other pine species, allowing longleaf pine to dominate
the stand. Exclusion of fire will allow other pine species and eventually hardwoods to dominate the
stand. Understory associates vary, depending on fire frequency, soil and topographic features.
Mixed Pine/Longleaf Pine - Stands are designated as Mixed Pine/Longleaf Pine (MP/LP) where
longleaf pine is less than 35 percent of the basal area but at least two stems per acre of any size exist.
In MP/LP stands, some form of regeneration must be utilized to accomplish longleaf pine restoration
goals. This type exists where the longleaf stand was clear-cut during the 1920s, leaving only a few
small or unmerchantable stems. Slash, loblolly, or pond pines, formerly restricted to the swamps edge
or drains by frequent fire, were able to invade the cut over longleaf pine stands. Typically, these stands
will have a mixture of 50- to 80-year-old slash, loblolly, or pond pine with scattered longleaf pine
averaging 130 years old. Understory species associated with this type are variations of southern rough,
low shrub, and grass species, depending on past and current fire activity.
Mixed Pine - Because the primary upland management goal for the refuge is to restore longleaf pine
communities wherever possible, slash pine, loblolly pine, and pond pine, whether in pure or mixed
stands are all classified collectively as “mixed pine” and identified on management maps as MP.
Predominately slash pine stands are described in SAF Type 84. Loblolly stands are described in
SAF Type 81. Pond pine stands are described in SAF Type 98. Where possible, longleaf pine will be
restored on these sites. Associated species are sweetbay, swamp tupelo (Nyssa sylvatica), pond
cypress, pond pine, loblolly bay, live oak (Quercus virginiana), red maple (Acer rubrum), water oak
(Quercus nigra), and laurel oak (Quercus hemisphaerica). On higher (but still poorly drained) sites, it
is associated with loblolly pine, longleaf pine, and several oaks. Ground cover on very wet sites may
be limited to sphagnum moss. Pure slash pine plantations often exist on disturbed high sites, while
others exist on poorly drained sites. Understory communities will vary depending on the site, the
amount of disturbance, and condition (Eyre 1980).
Wetland Hardwoods - These hardwoods grow on mineral soil wetland flats where fire seldom occurs.
A great many species, which grow on moist to wet sites, are associated with this hardwood type.
These include sweetbay, redbay, swamp tupelo, red maple, loblolly bay, sweetgum, water and laurel
oak, Lombardy poplar (Populus nigra), American holly (Ilex opaca), southern magnolia (Magnolia
grandiflora), pond cypress, and several pine species. The sites are described in SAF Type 104 (Eyre
1980). On Okefenokee Refuge, these are climax stands that succeed slash pine growing on wetter
sites. Many understory species may be associated with this type.
Section A. Comprehensive Conservation Plan 43
Ground Cover Vegetation Types
Upland understory vegetation responds to reintroduction of fire more rapidly than overstory species.
While understory species present may be influenced by overstory species and density, they are more
dependent upon elevation, soil conditions, fire frequency, intensity and season, and other
catastrophic events.
Ground cover types are classified in two ways: Classifications representing fuel types important for
fire management; and understory communities important for habitat management. Understory fuels
are described in the refuge’s Habitat and Wildlife Management Plan.
Wiregrass Ridges - Some of the highest parts of the refuge around Camp Cornelia and some islands
contain fairly well-drained sandy areas, which support wiregrass communities even without the
occurrence of frequent fire. Soils in these areas are probably Ridgeland sand. Longleaf pine and
scrub oaks are dominant on these areas because soils are too dry for competing species. Other
species found in these areas are paw paw (Asimina angustifolia), prickly pear cactus (Opuntia
humifusa), saw palmetto (Serenoa repens), and several species of dwarf blueberry.
Palmetto Terraces - These are somewhat poorly drained areas but slightly higher than the flatwoods.
Soil types may be Mandarin or Leon sands. In the absence of fire, these areas will contain saw
palmetto along with a mixture of gallberry, greenbriar, and grasses. Growing season fire in these
areas will stimulate wiregrass, piney woods dropseed (Sporobulus sp.), other warm season grasses,
shiny blueberry (Vaccinium myrsinites), and huckleberry species (Gaylussacia spp.), and other low
shrub species. Continued occurrence of growing season fire will cause gallberry, palmetto, and other
high shrub species to diminish and allow several longleaf pine associated understory communities to
dominate these areas.
Gallberry/Palmetto Flatwoods - These understory types are located on the traditional flatwoods areas
that make up about half of the refuge uplands. Soil types on these flatwoods may be Sapelo fine
sand or Pelham fine sand and higher Mascotte fine sand. In the absence of fire, gallberry will
dominate with a heavy palmetto component. Wax myrtle (Morella cerifera), hurrah bush, greenbriar,
dahoon holly, huckleberry, blueberry, wiregrass, piney wood dropseed, and other grasses are also
present. Frequent growing season fire will decrease the vigor of hardwood shrubs, allowing warm
season grasses, low shrubs, and other species to dominate.
Lower Gallberry Flatwoods - These understory types are in areas of wet or ponded soil types located
in depressions or adjacent to drainage ways. Gallberry and other hardwood shrubs dominate.
Scattered clumps of palmetto exist. These areas will burn during dormant or growing seasons.
Under a frequent growing season fire regime, wiregrass, piney woods dropseed, and other warm
season grasses and low shrubs will exist in place of the hardwood shrub thicket.
Upland/Wetland Transition Zones - These understory types are located in the mucky sand soil types
and generally form a thick band around the edge of most uplands. This tangle of thick hardwood
shrubs may blend into scrub/shrub areas at the edge of the swamp. Some of these areas may have
been burned regularly before the natural fire regime was disturbed; others may have burned only
during dry cycles. Where high-intensity fire has frequently occurred in the past, small open bands of
grasses and ferns exist within these zones. It is unknown whether these are areas formerly kept
open by fire that have not yet been invaded by hardwood shrubs, or if some other condition has kept
them open. Some historical accounts indicate the presence of wetland longleaf pine savannas
existing within these transition areas. An important unanswered question is whether a long series of
44 Okefenokee National Wildlife Refuge
growing season fires would create or restore open areas of longleaf pine with an understory of fire-dependent
grasses and shrubs. Longleaf pine stumps are occasionally found in these hardwood
shrub thickets. It would be impossible for longleaf pine to become established under present
conditions.
Endangered Plant Species
In addition to diminishing plant communities in the Okefenokee area, several native plant species are
of concern. Although there is only one known native plant species (hairy rattleweed) on the federal
endangered plant list, several plants on the Georgia list of plants of concern are located in the
Okefenokee area. These species include:
Hairy Rattleweed Baptisia arachnifera Endangered
Silver Buckthorn Sideroxylon alachuense Rare
Greenfly Orchid Epidendrum conopseum Unusual
Fly Catcher/Golden Trumpet Sarracenia flava Unusual
Hooded Pitcher Plant Sarracenia minor Unusual
Parrot Pitcher Plant Sarracenia psittacina Threatened
The following plants are located in the Okefenokee area but have not been confirmed on the refuge:
Purple Honeycomb Head Balduina atropurpurea Rare
Velvet Sedge Carex dasycarpa Rare
Dwarf Witch Alder Fothergilla gardenii Threatened
Hartwrightia Hartwrightia floridana Threatened
Pond Spice Litsea aestivalis Threatened
A comprehensive list of plants common to the refuge is located in Appendix IV.
FAUNA
Okefenokee Refuge is home to 48 species of mammals, 200 birds, 33 fish, 101 species of reptiles
and amphibians, and an undetermined number of invertebrates. The executive order establishing the
refuge stated its purpose as “a refuge and breeding ground for migratory birds and other wildlife.”
Although large numbers of waterfowl were reported to use Okefenokee Swamp at that time, they
were not specifically mentioned in the purpose of the refuge. It was recognized that this area was
important for a large variety of wildlife.
Even prior to the swamp becoming a refuge, it drew the attention of herpetologists. It quickly became
world renown for its amphibian and reptile populations. Besides the expanse of wetland habitats
inhabited by the American alligator (Alligator mississippiensis) and many species of frogs and turtles,
the refuge uplands contain many ephemeral ponds. Management of these ponds is important for the
flatwoods salamander (Ambystoma cingulatum), the striped newt (Notophthalamus perstriatus), the
gopher frog (Rana areolata aescpus), and other species.
Okefenokee Refuge is important for large populations of wading birds that find food and shelter.
Their movements from off-refuge sites and between the open prairies depend on food availability and
the depth of water. In the past, three to four nesting colonies were found each year. These birds,
along with the sandhill crane (Grus candensis), are considered to be indicators of the health of the
wetland system.
Section A. Comprehensive Conservation Plan 45
Because of its size, the refuge is valuable for species such as the black bear that have large home
ranges. A healthy population of the Florida black bear (Ursus americanus floridianus) exists today,
moving on and off the refuge depending on the resources available. The Florida panther (Felis
concolor coryi) once roamed the area as well; however, there have been no recent confirmed
sightings.
As the base for the food chain, healthy populations of invertebrates and fish are critical in the support
of the other fauna. Ensuring that the levels of environmental contaminants are monitored and
evaluated for potential risks within this group of fauna is a key factor to avoid degradation of the
Okefenokee Ecosystem.
Federally listed threatened or endangered species that make their home in the refuge include the red-cockaded
woodpecker, indigo snake, the wood stork, and the flatwoods salamander. The bald eagle
(Haliaeetus leucocephalus) passes through the area and has nested nearby, but has not been known
to nest on the refuge. The ivory-billed woodpecker (Campephilus principalis) was part of the
Okefenokee Ecosystem in the past but has not been seen since 1948.
The following are several other species that are of special concern on the refuge include: the gopher
tortoise; Sherman’s fox squirrel (Sciurus niger niger); round-tailed muskrat (Neofiber alleni exoristus);
Bachman’s sparrow (Aimophila aestivalis); Florida sandhill crane (Grus Canadensis pratensis);
neotropical migratory birds; black-banded sunfish (Enneacanthus chaetodon); mud sunfish
(Acantharchus pomotis); and banded topminnow (Fundulus cingulatus).
Appendix V contains a list of wildlife species native to the refuge. Appendix VI shows associations
between native wildlife species and the vegetation types.
Birds
The refuge was established for the conservation of migratory birds. There are many priority species,
both migratory and resident, for which the refuge provides habitat. Wading birds are the most
noticeable inhabitants of the wetland habitats and may actually serve as indicators of the health of the
Okefenokee Ecosystem. This includes the resident population of Florida sandhill cranes, which are
possibly unique because of their isolation. Wood ducks (Aix sponsa) also use the refuge throughout
the year. Other waterfowl species migrate through the refuge. Osprey (Pandion haliaetus), swallow-tailed
kites (Elanoides forficatus), and neotropical migratory birds also make use of the wetlands. In
addition, upland management efforts have focused primarily on the red-cockaded woodpecker, which
relies on mature longleaf pine uplands within the refuge. Many migratory and other resident bird
species are associated with these open pine forests on the refuge.
Wading Birds - Okefenokee Refuge supports large numbers of wading birds. Great egrets (Ardea
alba); great blue herons (Ardea herodias); white ibis (Eudomicus albus); and little blue herons
(Egretta caerulea) are common in the open prairies. In the early 1900s, hunting was a factor
influencing wading bird populations in the swamp. Wright and Harper (1913) and Hebard (1941)
noted that large colonies were present on Floyds Island, Chase, and Mixons Prairies. Today, Grand,
Chase, and Chesser Prairies appear to be used the most by wading birds. Surveys of waterbirds
have included monthly counts in selected prairies via an airboat. An annual aerial survey during the
breeding season has been used to check historic colony sites for activity.
Many of the wading birds currently utilizing the wetlands are foraging within the refuge and nesting
elsewhere. From 1992 through 2001, surveys indicate there has been an increase in use by white
ibis during the summer months. Drought conditions throughout the region during this time may have
46 Okefenokee National Wildlife Refuge
forced them to the large wetlands such as the Okefenokee Swamp that still had some water left.
However, many of the historic nest sites have been abandoned. Reasons for the loss of breeding
colonies remains unclear, but it may also be related to changing water levels and food resources.
The Fish and Wildlife Service, U.S. Geological Survey, and many state agencies have begun
collaborating to create a system of periodic inventories of colonial waterbirds in the United States.
Future refuge surveys may contribute to these efforts along with an understanding of regional
movements of these birds. Spatial distribution of wading birds reflects the location of appropriate
water levels for foraging. As water levels recede during prolonged periods of drought, ibis, egrets,
and herons shift their distribution to suitable feeding sites. With consistent survey methods, the
relative numbers of these common long-legged waders using the refuge, in association with their
location, may provide important information indicating the aquatic habitat