Horicon National Wildlife Refuge Fox River National Wildlife Refuge Draft Comprehensive Conservation Plan and Environmental Assessment

              U.S. Fish & Wildlife Service
Draft
Comprehensive
Conservation Plan and
Environmental Assessment
Horicon
National Wildlife Refuge
Fox River
National Wildlife Refuge
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.
The mission of the National Wildlife Refuge System 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 mission of the U.S. Fish & Wildlife Service is working with others to conserve,
protect, and enhance fish and wildlife and their habitats for the continuing benefit of the
American people.
Cover Photograph: U.S. Fish and Wildlife Service
Horicon and Fox River
National Wildlife Refuges
Draft Comprehensive Conservation Plan and Environmental Assessment
Table of Contents
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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Chapter 1: Introduction and Background ................................................................................................... 1
Introduction ................................................................................................................................................. 1
The U.S. Fish and Wildlife Service .............................................................................................................. 1
The National Wildlife Refuge System ......................................................................................................... 1
The Great Lakes Basin Ecosystem ............................................................................................................... 2
Horicon Marsh ............................................................................................................................................. 3
Horicon National Wildlife Refuge ................................................................................................................ 3
Fox River National Wildlife Refuge ............................................................................................................. 3
Refuge Purposes ......................................................................................................................................... 6
Refuge Visions ............................................................................................................................................ 6
Horicon National Wildlife Refuge ........................................................................................................ 6
Fox River National Wildlife Refuge ...................................................................................................... 6
Purpose and Need for Plan .......................................................................................................................... 6
History and Establishment ........................................................................................................................... 7
Horicon National Wildlife Refuge ........................................................................................................ 7
Fox River National Wildlife Refuge ...................................................................................................... 7
Legal Context .............................................................................................................................................. 9
Chapter 2: The Planning Process ............................................................................................................... 10
Internal Agency Scoping ............................................................................................................................ 10
Open Houses ............................................................................................................................................. 10
Focus Group Meeting ................................................................................................................................ 11
Summary of Issues, Concerns and Opportunities ...................................................................................... 11
Horicon National Wildlife Refuge ...................................................................................................... 11
Habitat Management .................................................................................................................. 11
Wildlife Management ................................................................................................................. 12
Visitor Services ............................................................................................................................ 12
State Highway 49 Issues ............................................................................................................. 12
Cultural Resources ...................................................................................................................... 12
Visibility of Horicon NWR as a National Resource ..................................................................... 12
Fox River National Wildlife Refuge .................................................................................................... 13
Wildlife Management ................................................................................................................. 13
Habitat Management .................................................................................................................. 13
Visitor Services ............................................................................................................................ 13
Cultural Resources ...................................................................................................................... 13
Administration and Logistics ....................................................................................................... 13
Preparation, Publishing, Finalization and Implementation of the CCP ...................................................... 14
Chapter 3: Refuge Environment .................................................................................................................. 15
Horicon National Wildlife Refuge .............................................................................................................. 15
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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Introduction ........................................................................................................................................ 15
Climate ............................................................................................................................................... 16
Geology and Glaciation ...................................................................................................................... 18
Soils ................................................................................................................................................... 19
Surface Hydrology .............................................................................................................................. 20
Wilderness Review ............................................................................................................................. 22
Archeological and Cultural Values ..................................................................................................... 22
Social and Economic Context ............................................................................................................. 23
Natural Resources .............................................................................................................................. 28
Habitats ...................................................................................................................................... 28
Wildlife ....................................................................................................................................... 28
Migratory Bird Conservation Initiatives ............................................................................................. 32
Wildlife Species of Management Concern ........................................................................................ 32
Horicon NWR Current Refuge Programs: Where We Are Today .............................................................. 32
Habitat Restoration ............................................................................................................................ 33
Habitat Restoration on the Refuge ............................................................................................. 33
Habitat Management ......................................................................................................................... 34
Managing Water Impoundments and Moist Soil Units ............................................................. 34
Mowing on Grasslands and Wet Meadows ............................................................................... 36
Haying on Grasslands .................................................................................................................. 37
Prescribed Fire on Uplands and Wetlands .................................................................................. 37
Wildfire Preparedness ................................................................................................................. 37
Controlling Invasive Plants .......................................................................................................... 37
Habitat Monitoring ............................................................................................................................. 39
Aerial Infrared – GIS Technology ............................................................................................... 39
Grassland Surveys ...................................................................................................................... 39
Prescribed Burning ...................................................................................................................... 39
Wildlife Monitoring and Research ..................................................................................................... 39
Surveys and Censuses ................................................................................................................. 39
Studies and Investigations .......................................................................................................... 41
Wildlife Management ........................................................................................................................ 42
Disease Monitoring and Control ................................................................................................. 42
Nest Structures ......................................................................................................................... 43
Predator and Exotic Wildlife Control ........................................................................................... 43
Coordination Activities ....................................................................................................................... 44
Interagency Coordination ................................................................................................................... 44
Public Recreation, Environmental Education and Outreach ............................................................... 44
Hunting ....................................................................................................................................... 46
Fishing ....................................................................................................................................... 46
Wildlife Observation ................................................................................................................... 47
Wildlife Photography ................................................................................................................... 47
Wildlife Interpretation ................................................................................................................. 47
Environmental Education ............................................................................................................. 47
Volunteer and Friends Contributions .................................................................................................. 47
Outreach ............................................................................................................................................ 48
Archaeological and Cultural Resources ............................................................................................. 48
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Law Enforcement ............................................................................................................................... 48
Fox River National Wildlife Refuge ........................................................................................................... 48
Introduction ........................................................................................................................................ 48
Climate ............................................................................................................................................... 49
Topography and Soils ......................................................................................................................... 49
Surface Hydrology .............................................................................................................................. 49
Archeological and Cultural Values ..................................................................................................... 49
Social and Economic Context ............................................................................................................. 49
Natural Resources .............................................................................................................................. 53
Habitats ...................................................................................................................................... 53
Wildlife ....................................................................................................................................... 57
Fox River NWR Current Refuge Programs: Where We Are Today ............................................................ 58
Habitat Management ......................................................................................................................... 58
Habitat Restoration ..................................................................................................................... 58
Wetland Restoration ................................................................................................................... 58
Dry Prairie Restoration ................................................................................................................ 58
Oak Savanna Restoration ............................................................................................................ 59
Water Level Management .......................................................................................................... 59
Moist Soil Management ............................................................................................................. 60
Prescribed Fire ............................................................................................................................. 60
Haying ......................................................................................................................................... 61
Controlling Invasive Plants ......................................................................................................... 61
Vegetation Surveys ............................................................................................................................. 61
Vegetation and Habitat Surveys ................................................................................................ 61
Wildlife Management ........................................................................................................................ 61
Wildlife Surveys and Censuses ................................................................................................... 61
Nest Structures ........................................................................................................................... 65
Pest, Predator, and Exotic Animal Control .................................................................................. 66
Coordination Activities ....................................................................................................................... 66
Interagency Coordination ................................................................................................................... 66
Partners, Volunteers and Cooperating Organizations ........................................................................ 66
Public Recreation, Environmental Education and Outreach .............................................................. 66
Deer Hunting ............................................................................................................................... 67
Law Enforcement ......................................................................................................................... 67
Chapter 4: Refuge Management ................................................................................................................. 68
Horicon National Wildlife Refuge .............................................................................................................. 68
Future Management Direction: Tomorrow’s Vision ........................................................................... 68
Refuge Vision .............................................................................................................................. 68
Goals, Objectives and Strategies ....................................................................................................... 68
Fox River National Wildlife Refuge ........................................................................................................... 79
Future Management Direction: Tomorrow’s Vision ........................................................................... 79
A Vision for Fox River National Wildlife Refuge ......................................................................... 79
Goals, Objectives and Strategies ....................................................................................................... 80
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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Chapter 5: Plan Implementation ................................................................................................................. 88
New and Existing Projects ......................................................................................................................... 88
Horicon Refuge Operating Needs Projects ........................................................................................ 88
Fox River Refuge Operating Needs Projects ..................................................................................... 91
Future Staffing Requirements .................................................................................................................... 92
Partnership Opportunities .......................................................................................................................... 92
Step-down Management Plans ................................................................................................................. 92
Archeological and Cultural Values ............................................................................................................. 92
Monitoring and Evaluation ......................................................................................................................... 94
Appendix A: Draft Environmental Assessment .................................................................................. 97
Appendix B: Glossary ........................................................................................................................... 163
Appendix C: Species List ..................................................................................................................... 169
Appendix D: Draft Compatibility Determinations ............................................................................ 187
Appendix E: Compliance Requirements ........................................................................................... 223
Appendix F: Priority Refuge Operational and Maintenance Needs ............................................ 229
Appendix G: Wildlife Species of Management Concern, Horicon NWR .................................... 231
Appendix H: Mailing List ...................................................................................................................... 241
Appendix I: List of Preparers ............................................................................................................. 245
Appendix J: Bibliography and References Cited ............................................................................ 249
Horicon and Fox River
National Wildlife Refuges
Draft Comprehensive Conservation Plan and Environmental Assessment
List of Tables
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Table 1: Watershed Characteristics, Horicon Marsh, Horicon NWR ............................................................ 22
Table 2: Socioeconomic Characteristics Dodge and Fond du Lac Counties, Wisconsin .............................. 24
Table 3: Area of Land by Land-Use Class For Dodge and Fond du Lac Counties (thousands of acres) ........ 26
Table 4: Dodge County Employment and Industry Data ................................................................................ 26
Table 5: Fond du Lac County Employment and Industry Data ....................................................................... 27
Table 6: 1995 Recreation-related Expenditures (1995 $ in thousands) of Visitors to Horicon NWR ........... 27
Table 7: Mississippi Valley Canada Goose Population Estimates (1948-1990) ............................................ 28
Table 8: Furbearer Trapping Totals, 2000-2005, Horicon NWR .................................................................... 44
Table 9: Socioeconomic Characteristics, Marquette County, Wisconsin ..................................................... 52
Table 10: Marquette County Employment and Industry Data ......................................................................... 53
Table 11: Summary of Spring 2004 Waterbird Surveys, Fox River NWR ....................................................... 62
Table 12: Marsh Birds Detected Per Point, Fox River NWR ............................................................................ 62
Table 13: Ten Most Common Bird Species Documented on Fox River NWR, Summer 2003 ......................... 63
Table 14: Bird Counts by Habitat Type, Fox River NWR ................................................................................. 63
Table 15: Frog and Toad Point Count Surveys, Fox River NWR ...................................................................... 63
Table 16: Sandhill Crane Survey Results, 1994-2005, Fox River NWR ........................................................... 64
Table 17: Long Lake Fish Population Survey, 2004, Fox River NWR ............................................................... 64
Table 18: Fox River and Backwaters Fish Population Survey, 2004, Fox River NWR ..................................... 65
Table 19: Muir Creek Fish Population Survey, 2004, Fox River NWR ............................................................. 65
Table 20: Additional Staffing Required to Fully Implement the CCP by 2021, Horicon NWR ........................ 92
Table 21: Step-down Management Plan Schedule, Horicon NWR ................................................................ 94
Table 22: Step-down Management Plan Schedule, Fox River NWR .............................................................. 95
Horicon and Fox River
National Wildlife Refuges
Draft Comprehensive Conservation Plan and Environmental Assessment
List of Figures
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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Figure 1: Location of Horicon NWR, Dodge and Fond Du Lac Counties, Wisconsin ....................................... 4
Figure 2: Location of Fox River NWR, Marquette County, Wisconsin ............................................................ 5
Figure 3: Historic Vegetation of the Horicon Marsh (1850s) ........................................................................... 8
Figure 4: Southeast Wisconsin and Location of Horicon NWR ..................................................................... 16
Figure 5: Conservation Lands in Southeastern Wisconsin, Horicon NWR .................................................... 17
Figure 6: Location of Rock River Watershed, Horicon NWR ......................................................................... 21
Figure 7: Current Landcover of Horicon NWR (2006 Classification) ............................................................. 29
Figure 8: Impoundments, Horicon NWR ........................................................................................................ 35
Figure 9: Existing Visitor Facilities, Horicon NWR ........................................................................................ 45
Figure 10: Current Land Cover, Fox River NWR ............................................................................................... 50
Figure 11: Historic Vegetation of the Fox River NWR ..................................................................................... 51
Figure 12: Future Habitat Conditions of Horicon NWR ................................................................................... 74
Figure 13: Proposed Visitor Facilities, Horicon NWR ...................................................................................... 77
Figure 14: Future Vegetation Cover, Fox River NWR ....................................................................................... 82
Figure 15: Current and Proposed Visitor Facilities, Fox River National Wildlife Refuge ................................ 86
Figure 16: Current Staffing Chart, Horicon NWR ............................................................................................ 93
Chapter 1:Introduction and Background
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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Chapter 1: Introduction and Background
Introduction
Twelve thousand years ago, glaciers created the
shallow peat-filled marshland basin known as the
“Little Everglades of the North,” or Horicon Marsh.
In the beginning, the Horicon Marsh supported a
vast array of wildlife and generations of native peo-ples.
When early European settlers came to this
land the Marsh began to undergo dynamic changes
lasting to the present day. The waters and wet soils
of the Marsh were alternately dammed, ditched,
drained, and farmed. Competing human demands
led to the Marsh being one of the most contested
pieces of real estate in the history of Wisconsin. The
battle was ultimately decided in favor of wildlife
conservation. Today, the Horicon Marsh is a national
treasure and a destination for hundreds of thou-sands
of visitors.
The U.S. Fish and Wildlife
Service
Horicon and Fox River National Wildlife Refuges
are administered by the U.S. Fish and Wildlife Ser-vice
(USFWS or Service). The USFWS is the pri-mary
federal agency responsible for conserving,
protecting, and enhancing the nation’s fish and wild-life
populations and their habitats. It oversees the
enforcement of federal wildlife laws, management
and protection of migratory bird populations, resto-ration
of nationally significant fisheries, administra-tion
of the Endangered Species Act, and the
restoration of wildlife habitat such as wetlands. The
Service also manages the National Wildlife Refuge
System.
The National Wildlife Refuge
System
Refuge lands are part of the National Wildlife
Refuge System, which was founded in 1903 when
President Theodore Roosevelt designated Pelican
Island in Florida as a sanctuary for Brown Pelicans.
Today, the system is a network of about 545 refuges
and wetland management districts covering about
95 million acres of public lands and waters. Most of
these lands (82 percent) are in Alaska, with approxi-mately
16 million acres located in the lower 48 states
and several island territories.
The National Wildlife Refuge System is the
world’s largest collection of lands specifically man-aged
for fish and wildlife. Overall, it provides habitat
for more than 5,000 species of birds, mammals, fish,
amphibians, reptiles, and insects. As a result of
international treaties for migratory bird conserva-tion
and other legislation, such as the Migratory
Bird Conservation Act of 1929, many refuges have
Fox squirrel. USFWS
Chapter 1:Introduction and Background
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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been established to protect migratory waterfowl
and their migratory flyways. Horicon Refuge serves
a dual purpose both as a critical nesting ground and
as an important link in the Mississippi Flyway net-work
of refuges that serve as rest stops and feeding
stations for migrating ducks and geese.
Refuges also play a crucial role in preserving
endangered and threatened species. Among the
most notable is Aransas National Wildlife Refuge in
Texas, which provides winter habitat for the highly
endangered whooping crane. Likewise, the Florida
Panther Refuge protects one of the nation’s most
endangered predators. Refuges also provide unique
recreational and educational opportunities for peo-ple.
When human activities are compatible with
wildlife and habitat conservation, they are places
where people can enjoy wildlife-dependent recre-ation
such as hunting, fishing, wildlife observation,
photography, environmental education, and environ-mental
interpretation. Many refuges have visitor
centers, wildlife trails, automobile tours, and envi-ronmental
education programs. Nationwide,
approximately 30 million people visited national
wildlife refuges in 2004.
The National Wildlife Refuge System Improve-ment
Act of 1997 established several important
mandates aimed at making the management of
national wildlife refuges more cohesive. The prepa-ration
of Comprehensive Conservation Plans
(CCPs) is one of those mandates. The legislation
directs the Secretary of the Interior to ensure that
the mission of the National Wildlife Refuge System
and purposes of the individual refuges are carried
out. It also requires the Secretary to maintain the
biological integrity, diversity, and environmental
health of the National Wildlife Refuge System and
identify the archeological and cultural values of Ref-uge
System lands.
The goals of the National Wildlife Refuge System
are to:
# Fulfill our statutory duty to achieve refuge
purpose(s) and further the System mission.
# Conserve, restore where appropriate, and
enhance all species of fish, wildlife, and plants
that are endangered or threatened with
becoming endangered.
# Perpetuate migratory bird, inter-jurisdictional
fish, and marine mammal populations.
# Conserve a diversity of fish, wildlife, and plants.
# Conserve and restore, where appropriate,
representative ecosystems of the United States,
including ecological processes characteristic of
those ecosystems.
# Foster understanding and instill appreciation of
fish, wildlife, and plants, and their conservation,
by providing the public with safe, high-quality,
and compatible wildlife-dependent public use.
Such use includes hunting, fishing, wildlife
observation and photography, and
environmental education and interpretation.
The Great Lakes Basin
Ecosystem
Horicon National Wildlife Refuge lies within the
Great Lakes Basin Ecosystem, a system shared
between eight states and Canada. This ecosystem is
made up of the world’s largest freshwater body,
which holds 18 percent of the world’s supply of
freshwater, covers 95,000 square miles, has 9,000
miles of shoreline, includes more than 5,000 tribu-taries,
and has a drainage basin of 288,000 square
miles.
The Basin contains critical breeding, feeding, and
resting areas as well as migration corridors for
waterfowl, colonial nesting birds, and many other
species of migratory birds. At the same time, the
Great Lakes Basin Ecosystem faces a variety of bio-logical
concerns, including the impact of exotic spe-cies,
the precarious nature of the aquatic community
structure, and high levels of contaminants. Certain
species within the Great Lakes basin have drawn
special concern. Fish species of special interest
include lake trout, lake sturgeon, lake whitefish,
walleye, Pacific salmon, and landlocked Atlantic
salmon and their forage. Native mussels are a man-agement
concern because they are being seriously
Lesser Yellowlegs. USFWS
Chapter 1:Introduction and Background
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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affected by zebra mussels and are in danger of extir-pation
from the Great Lakes Basin. Thirty-one spe-cies
of migratory birds that the Service considers of
management concern are found in the Great Lakes
ecosystem.
A recent survey of biological diversity in the
Basin identified 130 globally rare or endangered
plant and animal species. The Bald Eagle, Peregrine
Falcon, Kirtland’s Warbler, Piping Plover, Mitchell’s
satyr and Karner blue butterflies, Indiana bat, gray
wolf, lake sturgeon, deepwater sculpin, and pugnose
shiner are some of the threatened, endangered, and
candidate species that inhabit the Great Lakes eco-system.
Horicon Marsh
Horicon Marsh is the largest freshwater cattail
marsh in the United States, consisting of some
32,000 acres. The marsh is 14 miles long and 3 to 5
miles wide and has been classified as a palustrine
system dominated by persistent emergent vegeta-tion
and floating vascular aquatic beds. The south-ern
one-third of the marsh is managed by the
Wisconsin Department of Natural Resources (Wis-consin
DNR) while the northern two-thirds of the
marsh is managed by the U.S. Fish and Wildlife
Service.
In 1991 the marsh was designated a "Wetland of
International Importance" by the Ramsar Conven-tion,
an intergovernmental treaty that obligates 45
signatory nations to consider wetland conservation
in land-use planning, wise use of wetlands, establish
wetland reserves, and encourage wetland research
and data exchange. Designated sites in the United
States include Okefenokee National Wildlife Ref-uge,
Georgia/Florida; Everglades National Park,
Florida; and Chesapeake Bay Estuarine Complex,
Maryland/Virginia, to name a few.
In 1997, Horicon Marsh was accepted as a Glo-bally
Important Bird Area in American Bird Con-servancy’s
United States Important Bird Areas
program. The marsh received this recognition espe-cially
because more than 50 percent of the Missis-sippi
Flyway Canada Geese migrate through the
marsh during the fall and 2 percent of the flyway
population of Mallards migrates through during the
fall, with impressive numbers of other waterfowl. In
the fall of 2004, the Horicon Marsh was recognized
by the State as an Important Bird Area.
Horicon National Wildlife
Refuge
Horicon NWR is located 6 miles east of Waupan
in southeastern Wisconsin (Figure 1). Current Ref-uge
ownership consists of over 15,500 acres of
marsh and 5,600 acres of associated upland habitat.
Marsh habitat is seasonally to permanently flooded
and dominated by cattail, river bulrush, common
reed grass, sedges, and reed canary grass. Uplands
include nearly 2,000 acres of woodlands and 3,600
acres of grasslands.
Resource management at the Refuge involves
using a variety of techniques to preserve and
enhance habitats for wildlife, with programs both in
marsh and upland management. Marsh manage-ment
involves the manipulation of water levels to
achieve a desired succession of wetland plant com-munities
to meet the seasonal needs of wildlife pop-ulations.
Upland management includes establishing
and maintaining grasslands to provide nesting habi-tat
for ducks, Sandhill Cranes, and various song
birds. Management objectives include waterfowl
production and migratory bird use, with Redhead
ducks being emphasized.
Fox River National Wildlife
Refuge
The Fox River NWR, established in 1979, con-sists
of 1,004 acres of land located 10 miles north of
Portage, Wisconsin along State Highway F (Figure
2). The Refuge is administered by staff at Horicon
National Wildlife Refuge, approximately 40 miles to
the east.
The majority of the Refuge is shallow marsh,
sedge meadow, fen, or wet prairie wetlands. Upland
prairie and forest is also present on the Refuge. The
matrix of wetland and upland habitat provides
excellent habitat for both wetland and upland asso-ciated
wildlife, such as ducks, Sandhill Cranes, her-ons,
rails, songbirds, deer, turkey, and Bobwhite
Quail. Approximately 50 cranes use the Refuge dur-ing
the summer and more than 300 use it as a stag-ing
area during fall migration .
Current management on the Refuge is focused on
restoring historic upland habitats including oak
savanna and open grasslands. The natural hydrol-ogy
of the area is also being restored primarily
through the filling of agricultural drainage ditches.
Chapter 1:Introduction and Background
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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Figure 1: Location of Horicon NWR, Dodge and Fond Du Lac Counties, Wisconsin
Chapter 1:Introduction and Background
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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Figure 2: Location of Fox River NWR, Marquette County, Wisconsin
Chapter 1:Introduction and Background
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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Visitor facilities and opportunities are minimal but
include two parking areas, signs, and an annual deer
hunt.
Fox River National Wildlife Refuge is located
across the highway from a County Park named after
John Muir, a famous conservationist in the 19th and
early 20th centuries, who lived near the County
Park and the Refuge during part of his boyhood
years.
Refuge Purposes
Horicon National Wildlife Refuge was estab-lished
in 1941 under the authority of the Federal
Migratory Bird Conservation Act of 1929. The pur-pose
of the Refuge is: “for use as an inviolate sanctu-ary,
or for any other management purpose, for
migratory birds...”
Fox River was established in 1977 under two leg-islative
authorities:
“…for the development, advancement,
management, conservation, and protection of
fish and wildlife resources…” Fish and Wildlife
Act of 1956
“…for use as an inviolate sanctuary, or for any
other management purpose, for migratory
birds.” Migratory Bird Conservation Act,
February 18, 1929, 16 U.S.C. 715d
Refuge Visions
The planning team considered the past vision
statements and emerging issues and drafted the fol-lowing
vision statements as the desired future state
of each Refuge:
Horicon National Wildlife Refuge
Horicon NWR will be beautiful, healthy, and
support abundant and diverse native fish,
wildlife, and plants for the enjoyment and
thoughtful use of current and future
generations. The Refuge’s hydrologic regime
will include a functional Rock River riparian
system, with clean water flowing into and out of
the Refuge. The Refuge will be a place where
people treasure an incredible resource that
upholds the distinction of a Wetland of
International Importance.
Fox River National Wildlife Refuge
Fox River NWR will consist of diverse,
productive habitats and wildlife that provides
conditions found historically (pre-European
settlement) in the Upper Fox River watershed.
Specifically, the Refuge consists of a mosaic of
oak savanna, dry and wet prairie, fens, sedge
meadow, and shallow marsh habitats managed
to perpetuate a variety of native plant and
wildlife species, namely those of priority to the
Service.
Refuge staff, located at Horicon NWR, are a
multi-disciplined team dedicated to providing
quality habitat and wildlife management, as
well as quality wildlife-dependent public use
opportunities compatible with Refuge purposes.
Local communities and visitors value the
Refuge for the personal, financial, and societal
benefits it provides. A strong conservation ethic
is promoted in the surrounding communities
where both John Muir and Aldo Leopold were
inspired by nature’s beauty, complexity, and
value.
Purpose and Need for Plan
This CCP articulates the management direction
for Horicon and Fox River National Wildlife Ref-uges
for the next 15 years. Through the develop-ment
of goals, objectives, and strategies, this CCP
describes how the refuges also contribute to the
overall mission of the National Wildlife Refuge Sys-tem.
Several legislative mandates within the
National Wildlife Refuge System Improvement Act
of 1997 have guided the development of this plan.
These mandates include:
# Wildlife has first priority in the management of
refuges.
# Wildlife-dependent recreation activities, namely
hunting, fishing, wildlife observation, wildlife
photography, environmental education and
interpretation are priority public uses of
refuges. We will facilitate these activities when
they do not interfere with our ability to fulfill
the refuges’ purpose or the mission of the
Refuge System.
# Other uses of the Refuge will only be allowed
when determined appropriate and compatible
with Refuge purposes and mission of the
Refuge System.
Chapter 1:Introduction and Background
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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The plan will guide the management of Horicon
NWR and Fox River NWR by:
# Providing a clear statement of direction for the
future management of each Refuge.
# Making a strong connection between Refuge
activities and conservation activities that occur
in the surrounding area.
# Providing Refuge neighbors, users, and the
general public with an understanding of the
Service’s land acquisition and management
actions on and around the Refuge.
# Ensuring the Refuge actions and programs are
consistent with the mandates of the National
Wildlife Refuge System.
# Ensuring that Refuge management considers
federal, state, and county plans.
# Ensuring that Refuge management considers
the preservation of historic properties.
# Establishing long-term continuity in Refuge
management.
# Providing a basis for the development of budget
requests on the Refuge’s operational,
maintenance, and capital improvement needs.
History and Establishment
Horicon National Wildlife Refuge
Nearly twelve thousand years ago, glaciers cre-ated
the shallow peat-filled marshland basin known
today as the Horicon Marsh (Figure 3). Since that
time, nomadic hunters and gatherers succeeded by
numerous Indian cultures, including the Paleo hunt-ers,
the Hopewellian People, and the Woodland Indi-ans
have lived near this marsh. In fact,
archaeological records confirm nearly every prehis-toric
Indian culture known to the Upper Midwest
lived near Horicon Marsh at one time or another.
When early European settlers came to this land
they settled among the Indian villages and estab-lished
their first modern settlement – the town of
Horicon. In 1846, a dam was built on the Rock River
to power a sawmill and to develop steamboat navi-gation.
The dam created Lake Horicon, which at the
time was considered to be the largest human-engi-neered
lake in the world. At this time water levels in
the marsh were raised by 9 feet, but after 23 years
of disputes, the dam was removed and the marsh
was returned to a haven for wildlife.
The era that followed was one of hunting clubs
and market hunting days, which lasted to the early
1900s. At this time, other interests appeared to
influence and dominate the marsh, most notably,
moist-soil agriculture. Root crop cultivation soon
became the incentive to drain the lands around the
marsh, and within a short time, the entire marsh.
Despite these efforts, attempts to farm the peat soil
failed and left behind natural resource devastation
that could have hardly been foreseen.
In 1921, several conservation-minded individuals
began a fight to restore the marsh, and 6 years later
the state legislature passed the Horicon Marsh
Wildlife Refuge Bill. This action provided for the
construction of a dam to restore marshland water
levels and permit the acquisition of lands in and
around the marsh which led to the establishment of
Horicon National Wildlife Refuge in 1941.
Fox River National Wildlife Refuge
Fox River National Wildlife Refuge was autho-rized
by the USFWS Director in 1978 under the
Service’s Unique Wildlife Ecosystem Program for
the purposes of protecting an area known as the Fox
River Sandhill Crane Marsh from further drainage
for agricultural purposes. The marsh was known as
an important breeding and staging area for the
Sandhill Crane. The following paragraphs recount
the events leading up to establishment of the Ref-uge.
During the summer of 1978, Federal authorities
documented activities on a marsh adjacent to
County Road F that appeared to be in violation of
Section 404 of the Federal Water Pollution Control
Act. A court case (Civil No. 78-c-367) subsequently
followed and determined that a substantial portion
School visit to Horicon NWR.
Chapter 1:Introduction and Background
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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Figure 3: Historic Vegetation of the Horicon Marsh (1850s)
Chapter 1:Introduction and Background
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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of the ditching and filling activities within the marsh
boundaries were within the limits of Section 404
jurisdiction. The U.S. Attorney agreed to prosecute
the case. A preliminary injunction was filed on July
28, 1978, in U.S. District Court, Eastern District of
Wisconsin, that restrained the landowner from fur-ther
ditching and filling activities.
Subsequently, the court issued a Consent Decree
whereby the Service agreed to purchase the subject
631-acre property after a specified amount of resto-ration.
The Fox River National Wildlife Refuge was
formally established during the spring of 1979 when
the Service acquired the property to fulfill the Con-sent
Decree.
Planning documents completed at the time of
Refuge establishment recommended a Refuge
boundary encompassing 1,043 acres, the minimum
size needed to meet Service goals and objectives.
Legal Context
In addition to the executive order establishing
the Refuge, and the National Wildlife Refuge Sys-tem
Improvement Act of 1997, several federal laws,
executive orders, and regulations govern adminis-tration
of Horicon NWR and Fox River NWR.
Appendix E contains a partial list of the legal man-dates
that guided the preparation of this plan and
those that pertain to Refuge management.
Entrance sign at Fox River NWR. USFWS
Chapter 2:The Planning Process
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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Chapter 2: The Planning Process
The Draft CCP for Horicon NWR and Fox River
NWR has been written with input and assistance
from citizens, non-governmental organizations
(NGOs), and staff from state and local agencies. The
participation of these stakeholders is vital and all of
their ideas have been valuable in determining the
future direction of the refuges. Refuge and Service
planning staff are grateful to all of those who have
contributed time, expertise and ideas throughout
the comprehensive conservation planning process.
We appreciated the enthusiasm and commitment
expressed by many for the lands and living
resources administered by the Horicon NWR.
Internal Agency Scoping
The CCP planning process began in January
2005 with a kickoff meeting between Refuge staff
and regional planners from the Service’s office in
the Twin Cities. The participants in this “internal
scoping” exercise reviewed vision statements and
goals, existing baseline resource data, planning doc-uments
and other refuge information for Horicon
NWR and Fox River NWR. In addition, the group
identified a preliminary list of issues, concerns and
opportunities facing the refuges that would need to
be addressed in the CCP.
A list of required CCP elements such as maps,
photos, and GIS data layers was also developed at
this meeting and during subsequent e-mail and tele-phone
communications. Concurrently, the group
studied federal and state mandates plus applicable
local ordinances, regulations, and plans for their rel-evance
to this planning effort. Finally, the group
agreed to a process and sequence for obtaining pub-lic
input and a tentative schedule for completion of
the CCP. A Public Involvement Plan was drafted
and distributed to participants immediately after
the meeting.
Internal scoping continued with a meeting at the
Regional Office in Fort Snelling, Minnesota in
March 2005. Staffers from Region 3, including
supervisors, planners, and biologists covering wild-life/
habitat and migratory birds joined the Horicon
NWR Refuge Manager for a discussion on the
issues, public response and a number of consider-ations
related to the CCP.
Open Houses
Public input was encouraged and obtained using
several methods, including open houses, written
comments during a public scoping period, issue-based
focus groups, and personal contacts.
Initial public scoping for the CCP for Horicon
NWR and Fox River NWR began in March 2005
with a series of open house events held in Montello
(Fox River), Waupun and Mayville, Wisconsin. Turn-out
was light with approximately 25 people in total
attending.
Prairie habitat, Horicon NWR. USFWS
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Those interested in making written comments
had until April 15, 2005 to submit them. Comments
could be sent by U.S. mail, e-mail, or via the Horicon
planning website on the Internet. Approximately 20
comment forms and other written comments were
submitted to the Refuge during the scoping process.
Focus Group Meeting
On June 1-2 (Horicon) and June 7 (Fox River),
2005, all-day public focus group workshops were
held to obtain more detailed input on the issues and
opportunities identified in preliminary scoping and
to begin development of alternatives. Twenty-eight
people, representing Wisconsin DNR, Refuge staff,
conservation organizations, neighboring communi-ties,
Refuge users, and other stakeholders attended
these discussions.
Summary of Issues, Concerns
and Opportunities
A large list of issues, concerns, and opportunities
was generated during internal Refuge scoping, pub-lic
open house sessions and workshops. The goals,
objectives, and strategies in Chapter 4 are intended
to address this list. The major issues addressed in
the CCP are described as follows:
Horicon National Wildlife Refuge
Habitat Management
Upland habitat restoration and management
The Refuge could restore areas to historic vege-tation
or create habitats that are lacking in the area.
Possibilities include managing the Refuge’s east
side as hardwoods mixed forest and the west side as
grassland (historic vegetation). Or we could convert
all uplands to native grassland on the entire Refuge
since grasslands are lacking in area.
Invasive plant species
Habitat structure on the Refuge is threatened by
invasive, non-native plant species such as reed
canary grass and leafy spurge. Invasive plant spe-cies
are often those introduced from Europe or Asia
and they have no native biological controls in the
United States. They are often early successional
species adapted to disturbance, they move in
quickly, and are difficult to control with traditional
methods such as prescribed fire.
Land Acquisition (authorized boundary and
adjustments)
Several participants suggested that the Refuge
and partners actively pursue land protection within
the 1995 expansion boundary. Conservation mea-sures
within the expansion area will help to protect
the Horicon Marsh.
Off-Refuge involvement and external threats (i.e.
watershed protection)
A large portion of the Interagency Workshop was
spent discussing sedimentation and environmental
contaminant issues related to the Marsh. All partici-pants
agreed that soil conservation measures in the
upper watershed would go far in reducing these
problems. However, increasing wetland conserva-tion
and encouraging new agricultural practices will
be a huge task that will require innovative
approaches to public and private partnerships.
A proposal for a wind energy facility adjacent to
the Refuge, which could include up to 133 wind tur-bines
to generate electricity, was also discussed dur-ing
internal scoping. The primary concern was the
potential impact to migratory birds and resident
bats from striking the towers and turbines that
would reach up to 389 feet above ground level.
Water Management:
The management of water levels is the key to
maintaining a viable Marsh. However, the State por-tion
of the marsh, Lake Sinnissippi, and other down-stream
waterbodies control how much water the
Refuge can hold and release. The CCP should
decide how the pools of Horicon NWR should be
managed and could include filling ditches, improv-ing
dikes, and adding or removing water control
structures.
Refuge road, Horicon NWR
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Wildlife Management
Migratory Birds
Data suggests that predation loss is high for
waterfowl and other ground-nesting birds. The
small ratio of uplands to wetland area may be a fac-tor.
The CCP should decide if the Refuge should be
managed for birds in migration and accept a high
nesting loss or if predator control is a viable option.
Carp Control
Carp are causing a lot of damage to the wetland
habitat of the Horicon Marsh. Carp control mea-sures
include trapping/removal and periodic appli-cation
of the pesticide Rotenone. However, despite
control measures, carp populations remain too high.
Threatened and endangered species
People enjoy seeing Bald Eagles, which are the
most conspicuous and spectacular listed species that
occurs at Horicon NWR. It is highly probable that
Whooping Cranes, recently re-introduced to Wis-consin,
will expand their use of the Refuge. Indeed,
one Whooping Crane has already been using the
Refuge for four years in a row, while a second crane
used the Refuge in 2004 for at least a few days.
Visitor Services
Deer hunting
Horicon NWR supports a number of hunts for
white-tailed deer including archery, firearm, and
special opportunities for hunters with disabilities. If
the deer herd is above desirable population levels, it
may cause increased habitat damage, deer/auto col-lisions
and neighboring crop damage. In addition,
chronic wasting disease is a new concern within the
State. Increased hunting may be a necessary con-trol
measure for all of the above reasons.
Waterfowl hunting
Horicon NWR has been entirely closed to water-fowl
hunting since 1966. In 1953, the perimeter of
the Refuge was opened for goose hunting, with
goose blinds set up on a 7-mile narrow strip. This
was originally supposed to be an experiment, but it
lasted until 1966. It was basically the precursor to
the intensive hunting zone that occurs today on pri-vate
land around the whole Refuge. Some hunters
who use the State portion of the marsh have
expressed an interest in hunting on the federal Ref-uge.
However, many hunters also value the fact that
the sanctuary status of the federal Refuge also
holds migrating birds in the area for longer periods
of time.
Upland game hunting
Additional upland game hunting opportunities
were identified including longer seasons on squir-rels,
rabbits, and pheasants and a possible spring
Wild Turkey hunt.
Fishing
Opportunity and demand for angling on Horicon
NWR is limited due to shallow water, turbidity, and
higher-quality fishing opportunities in the local
area. The Refuge is closed to motorboat access dur-ing
the open water season. However, some ice fish-ing
may be feasible, especially if limited to specific
sites, with no permanent shanties and no motorized
access.
Wildlife observation
Horicon NWR receives 450,000 visitors a year
with heavy visitation in the fall during waterfowl
migration. Most of these visits are concentrated on
the auto tour route, walking trails, and the floating
boardwalk. The CCP would be the proper place to
discuss new facilities or accommodation for visitors.
State Highway 49 Issues
State Highway 49, a high-volume traffic roadway,
bisects the northern edge of the Horicon Marsh.
Many participants pointed out that wildlife road kill
on Hwy 49 is excessive. In addition, contaminants
from Hwy 49 include the potential for a toxic spill,
road salts, grain spills and trash deposited along
road.
Cultural Resources
As a federal conservation agency, the Service has
a responsibility for the protection of the many
known and undiscovered cultural resources located
on Refuge lands.
Visibility of Horicon NWR as a National Resource
Horicon Marsh is recognized locally, nationally
and internationally as a valuable natural resource,
especially in light of its long, colorful history and
designation as a wetland of international impor-tance.
However, some participants believed that
more could be done to raise the stature of the Ref-uge,
and perhaps funding levels, internally within
the National Wildlife Refuge System.
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13
Fox River National Wildlife Refuge
Wildlife Management
The Refuge was established for nesting Sandhill
Cranes during a time when the species was declin-ing
throughout the Midwest. Crane numbers have
increased significantly during the last 20 years. The
reintroduction of Whooping Cranes to Wisconsin
has created the likelihood that a nesting pair may
establish on the Refuge. In fact, an individual
Whooping Crane used the area in 2004.
Habitat Management
Historic habitat restoration
General Land Office surveys from 1832 suggest
much of the landscape around the Refuge was his-torically
dry prairie and oak savanna. The Refuge
has been working to restore the uplands to these
habitats.
Refuge inholdings and cooperative work with
neighbors
The Refuge contains some small parcels of pri-vate
lands within the authorized boundaries. A gen-eral
desire was expressed to encourage cooperative
work with landowners since we share habitats and
wildlife.
Additional land conservation
Scoping participants wondered if there was a
need for land protection outside existing approved
boundaries. It was suggested that adjacent habitat
could be restored or managed to complement Ref-uge
goals.
Visitor Services
Deer Hunting
Currently the only public use allowed on the Ref-uge
is deer hunting. Options discussed include more
intensive antlerless harvests and total or periodic
closures knowing that the chronic wasting disease
concern may prevent the Refuge from decreasing
the hunting pressure.
Additional hunting for small game and Wild
Turkey
A few participants wanted to see more hunting
opportunities on the Refuge. Law enforcement con-cerns
and the relatively small size of uplands on the
Refuge may preclude some hunts. The Refuge may
be able to support a limited spring hunt for Wild
Turkeys on the 250-300 acres of uplands available.
Squirrel hunting on these acres is also a possibility.
Fishing access
Boat access for fishing is available along the Fox
River. Many people have expressed interest in fish-ing
on Long Lake. The 1-mile hike from the parking
lot to the potential fishing spot is expected to limit
the number of anglers. Boating access may need to
be seasonally restricted to reduce disturbance of
migratory birds, especially nesting Sandhill Cranes.
Potential Ice Age Trail crossing
The National Park Service has suggested that
the Service establish a segment of the Wisconsin Ice
Age State and National Trail through the Refuge.
Trail location, maintenance, and restrictions on off-road
vehicles are addressed in the CCP.
On-site environmental education and
interpretation
Participants suggested that the Refuge could do
more with the local community and schools. Devel-oping
a cadre of teachers and volunteers who could
lead field trips was mentioned as one strategy.
Cultural Resources
As a federal conservation agency, the Service has
a responsibility for the protection of the many
known and undiscovered cultural resources located
on Refuge lands.
Administration and Logistics
Refuge staffing and law enforcement
The Refuge has been administered by the Hori-con
NWR, located a 1-hour drive east of the Fox
River NWR. This arrangement will probably con-tinue
due to funding constraints and the fact that
the Refuge will be relatively low-maintenance after
ongoing habitat restoration.
Visitors to Horicon NWR. USFWS
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Preparation, Publishing,
Finalization and
Implementation of the CCP
The Draft CCP and Environmental Assessment
(EA) for Horicon NWR and Fox River NWR were
prepared by a team that includes staff from the
Horicon NWR and USFWS Regional Office, and
with the assistance of a private contractor. The
CCP/EA will be published in two phases and in
accordance with the National Environmental Policy
Act (NEPA). The Draft EA (Appendix A) presents a
range of alternatives for future management and
identifies the preferred alternative, which is also the
Draft CCP. A public review period of at least 30
days, which will include a public meeting, will follow
release of the draft plan.
Verbal and written comments received by the
Service will be incorporated where appropriate and
perhaps result in modifications to the preferred
alternative or in the selection of one of the other
alternatives. The alternative that is ultimately
selected will become the basis of the ensuing Final
CCP. This document then, becomes the basis for
guiding management over the coming 15-year
period. It will guide the development of more
detailed step-down management plans for specific
resource areas will also underpin the annual budget-ing
process for refuge operations and maintenance.
Most importantly, it lays out the general approach to
managing habitat, wildlife, and people at the Hori-con
NWR and Fox River NWR that will direct day-to-
day decision-making and actions.
Chapter 3:Refuge Environment
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
15
Chapter 3: Refuge Environment
Horicon National Wildlife
Refuge
Introduction
Twelve thousand years ago, a colossal Ice Age
glacier scraped and gouged out a trough that over
the millennia has become a shallow, peat-filled
marshland basin. It is known as Horicon Marsh, or
the “Little Everglades of the North.” Since the
Pleistocene Epoch – a frozen era that ended just a
moment ago in the vast reaches of our planet’s
geologic past – momentous changes have swept
over the land. The climate warmed considerably,
extinction claimed scores of North American
megafauna such as mammoths and mastodons, and
a newly arrived, potent force of nature and agent of
ecological change – Homo sapiens – strode
confidently across the continent.
Horicon NWR was established for the protection
and conservation of migratory waterfowl. It is
located on the west branch of the Rock River in
southeastern Wisconsin, 43 miles west of Lake
Michigan and 65 miles northwest of Milwaukee
(Figure 4).
The Refuge comprises the northern two-thirds
(21,400 acres) of the 32,000-acre Horicon Marsh;
the Horicon Marsh State Wildlife Area, managed
by the Wisconsin Department of Natural Resources
for hunting, fishing, and other public use activities,
occupies the southern third of the marsh
(approximately 11,000 acres). See Figure 5.
Horicon Marsh rests in the shallow peat-filled
lake bed carved out by the Green Bay Lobe of the
Wisconsin Glacier those thousands of years ago.
The basin is 14 miles long and from 3 to 5 miles
wide. The marsh is bounded on the east by the
Niagara escarpment, a ridge climbing rather
abruptly to an elevation of 1,100 feet, approximately
250 feet above the marsh. The landscape west of the
Refuge rises very gently and is dotted with many
small prairie potholes and several shallow lakes.
Features of the area’s Ice Age heritage abound
in the surrounding landscape. Ice Age glaciation –
in particular what is known as the Wisconsin
Glaciation, from 80,000 to about 12,000 years ago –
which reached as far south as Rock County south of
the Refuge, left behind tell-tale evidence such as
eskers, drumlins, moraines, and kettles (NPS, no
date).
Horicon Marsh is the largest freshwater cattail
marsh in the United States, and up to one million
Canada Geese visit the Refuge each fall, with a
peak of 300,000 birds. The Refuge and marsh also
provide habitat for many species of wetland birds
including ducks, cranes, pelicans, herons and
shorebirds.
Areial photograph shows Horicon NWR. USFWS
Chapter 3:Refuge Environment
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The ecological importance of Horicon Marsh is
recognized not just nationally but internationally.
In 1990, Horicon Marsh was designated a “Wetland
of International Importance” by the Ramsar
Convention, an intergovernmental treaty that
obligates 45 signatory nations to consider wetland
conservation through land use planning, wise use of
wetlands, establishment of wetland reserves, and
wetland research and data exchange. In 1997, the
Horicon Marsh was named a Globally Important
Bird Area in American Bird Conservancy’s United
States Important Bird Areas program. The marsh
received this recognition for several reasons, but
especially because: 1) more than half of the
Mississippi Flyway Canada Geese migrate through
the marsh during the fall, and 2) two percent of the
biogeographic population of mallards migrates
through during the fall, with impressive numbers of
other waterfowl.
Climate
As would be expected from its location in the
northern Midwest, deep in the heart of the
continent and far from the moderating sea coasts,
Horicon NWR’s climate is typically continental,
with cold winters and warm summers. The Refuge
has an average annual temperature of 46 degrees
Fahrenheit. July is the warmest month with an
average temperature of 73 degrees Fahrenheit. The
coldest month is January with an average
temperature of 21 degrees Fahrenheit.
Figure 4: Southeast Wisconsin and Location of Horicon NWR
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Figure 5: Conservation Lands in Southeastern Wisconsin, Horicon NWR
Chapter 3:Refuge Environment
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Annual precipitation is about 28 inches, with
approximately 20 inches of this occurring between
April and September, and falling as rain. Snowfall
averages 34 inches annually. Freezing usually
begins around October 1 and lasts until May 12,
making the length of the growing season an
average of 142 days. Wind speeds average about
10.6 miles per hour throughout the year. March,
April, and November have the highest wind speeds
with an average of 12 miles per hour. Winds are
normally from the south in the summer and the
west in the winter (USFWS, 1995).
Geology and Glaciation
The Niagara Escarpment is a layer of bedrock
that consists of limestone cliffs and talus slopes. It
abuts the eastern edge of Horicon Marsh and
extends further south; north of Horicon Marsh, it
reaches into the town of Oakfield and continues all
along the eastern shore of Lake Winnebago to
Green Bay and Door County. Overall, the Niagara
Escarpment extends for a distance of 230 miles in
Wisconsin.
The escarpment continues beneath Lake
Michigan, Lake Huron, Lake Erie, and the State of
Michigan, and reappears as a surface feature at
Niagara Falls in New York. In other words, the
same layer of rock that forms the gentle hills to the
east of the marsh extends 500 miles to the east and
is the same rock layer over which the Niagara River
plunges at Niagara Falls. It has been said that
residents of eastern Wisconsin live, work, and play
on the backside of Niagara Falls.
The escarpment or “Ledge” is up to 250 feet
high, but the maximum thickness of this rock layer
varies from 450 to 800 feet. The Ledge’s rock –
dolomitic limestone – is more than 400 million years
old. In comparison, the Appalachian Mountains are
about 480 million years old and the Rockies about
70 million. However, the Ledge can be considered
even younger because it was reformed at its current
location by the last glacier, which receded from this
area about 12,000 years ago.
The durability of the Ledge is due to the erosion-resistant
sedimentary rocks that form it: limestones
and dolomites laid down in the Silurian Period from
443 to 417 million years ago. Dolomite, the main
ingredient, was formed by calcium and magnesium
carbonate [CaMg(CO3)2] deposited from
decomposing shells and skeletons of primitive sea
life that lived in a subtropical coral reef. At the
time, this ancient inland sea’s basin covered all of
what is now lower Michigan, Lake Michigan and
eastern Wisconsin.
A soft, impermeable layer called Maquoketa
shale lies beneath the Ledge. It was formed during
the Ordovician Period (about 480 million years ago)
when thick deposits of mud were laid down from
erosion in the Appalachian Mountains rising to the
east as North America collided with Africa to form
the supercontinent of Pangea. Today, this shale
erodes quickly where it is exposed, allowing the
dolomite to continually break off and form a new
cliff face, the same process can be measured at
Niagara Falls in miles per century. It is in part
because of this relatively soft shale layer that
Horicon Marsh was later formed by glacial action.
It is also partly because of this impermeable
shale bed that many crystal-clear springs form at
the base of the Ledge. Fed by precipitation, water
flows down slope at and beneath the surface of the
Ledge through the dolomite, which is highly
fractured into perpendicular horizontal and vertical
joints. Springs form at the base of the Ledge where
Breakneck Ledge, Horicon NWR
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glaciers deposited drift consisting in part of
impermeable clays. Water eventually drains into
Horicon Marsh or Lake Winnebago.
Besides ancient marine life and the resulting
upwarping, glacial ice also molded the Ledge. In
some places successive glaciers obliterated it,
making it a difficult landscape feature to trace in
southern Wisconsin. In other places, glaciers
created huge fissures and crevasses. The Ledge
would certainly be higher and sharper without the
impacts of glacial scouring and bulldozing (USFWS,
no date-a).
Vast continental glaciers altered Wisconsin’s
landscape many times during a series of glacial
periods over at least the last one million years
through four different Ice Ages. Named for the
location of their most southerly advance, those Ice
Ages are called the Nebraskan, Kansan, Illinoisan,
and Wisconsin. The Horicon Marsh that we see
today was most affected by the Wisconsin
Glaciation, the most recent of the Ice Age advances.
The Wisconsin Glaciation lasted from 80,000
years ago to about 12,000 years ago, leaving behind
a terminal moraine 900 miles in length throughout
the state. The enormous glaciers, more than a mile
thick in places, did not simply come and go, leaving
no trace of their existence. Rather, they advanced
and retreated gradually and on majestic scale, and
in so doing shaped the landscape of today’s
Wisconsin and the other Great Lakes states. The
five Great Lakes themselves, also a product of the
extensive glaciation, are visible from the moon.
While not visible from the moon, other glacial
features such as bogs, fens, lakes, marshes,
erratics, moraines, kames, eskers, drumlins,
potholes, and kettles, are quite evident to earth-bound
observers and serve as constant reminders of
Horicon Marsh’s icy past.
The Green Bay lobe of the Wisconsin Glaciation
gripped eastern Wisconsin and scoured out Green
Bay, the Fox River, Lake Winnebago, Horicon
Marsh, and the Rock River basin reaching as far
south as Janesville and Madison. As the glacier
lobes receded, flowing meltwater pooled, forming
large lakes where silt and clay collected. In the Fox
River valley, Green Bay, and Lake Winnebago are
small remnant depressions of one such huge lake,
Glacial Lake Oshkosh (Attig et al., 2005).
The glacier receded in stages, creating
recessional moraines that mark a temporary, icy
delay in their retreat. The City of Horicon on the
south end of the Marsh is built on such a recessional
moraine. For awhile, it acted as an earthen dam,
holding back melting ice waters into Glacial Lake
Horicon, 51 square miles in size, and five times
larger than Lake Mendota. The headwaters of the
Rock River formed near this lake. Rising glacial
melt waters eventually wore a path over and down
through the moraine. Over time, water flow broke
through the dam, and water levels on the lake
lowered, draining the lake. The lowering of the
glacial lake level stopped abruptly, when the Rock
River reached the hard Galena-Dolomite rock
strata (layer) in its bed at Hustisford Rapids, 7
miles downstream from Horicon Marsh. This solid
rock strata has acted as a natural dam, maintaining
a fairly constant level of water, north to the Fond
du Lac County line. As crushed gravel, sand, fine
silts and clays were deposited in the Glacial Lake
Horicon basin, it evolved into the marsh it is at
present.
Today, Horicon Marsh is considered an extinct
glacial lake. The manmade dam on the Rock River
in the City of Horicon is located conveniently within
the recessional moraine that once held back the
meltwaters for Glacial Lake Horicon. The
headquarters for the Horicon Marsh State Wildlife
Area is built on a large drumlin (an elongated hill or
ridge of glacial drift or till), with many more
drumlins in a fan-shaped pattern to the south of the
City of Horicon in Dodge and Jefferson counties.
Other moraines occur on the northeast and
northwest corners of Horicon NWR. Glacial
erratics – boulders carried away from their place of
origin and deposited elsewhere as the glacier
melted – dot the landscape and are especially
noticeable after prescribed fires (USFWS, no date-b).
Soils
The major factors in soil formation are parent
material, climate, relief, topography, vegetation,
and time. Soils in the Horicon NWR area are the
result of atmospheric, chemical, and organic forces
modifying the surface of the glacial deposits. The
glacial deposits consist of unsorted sand, gravel,
boulders, clay, fragments of local limestone and
sandstone bedrock, and igneous and metamorphic
rock from outside the region. Soils include those of
a glacial deposit origin and vary between poorly
drained peat and muck types, transition silty loam
soils interspersed with sandy loam and clay, to
excellent agricultural soils being intensively
farmed. Topsoil depths range from 10 to 14 inches.
Chapter 3:Refuge Environment
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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Soil types around the Refuge include Houghton
muck and peat soils, which cover about 90 percent
of the Refuge and other soils that cover upland
areas and margins surrounding the marsh. Soil
groups associated with the margins of the marsh
include the following:
# Stoney land wet and maumee sandy loams –
found around drainage ways and on foot slopes
of moraines on the east side of the Refuge. They
are very poorly drained sandy soils with
rounded glacial stones one to two feet in
diameter. Depth of groundwater is zero to three
feet.
# Pella – Virgil silt loams – transition soils located
between the marsh and the uplands. They are
gently sloping somewhat poorly drained silty
loam soils underlain by sandy loam glacial till at
depths of 3 to 4 feet. These soils have seasonally
high groundwater table and may be inundated
for short periods of time.
# LeRoy – Theresa silt loams – consisting of
deep, gently sloping to steep, well-drained soils
located in the upland areas. These soils are
typical of the farmlands surrounding the
Refuge. Groundwater on these soils is at a
depth of 6 feet or greater.
# Beecher – Morley silt loams – prominent on the
uplands along the central eastern border and
the northern tip of the Refuge. These soils are
poorly to well-drained, level to steep silt loams
underlain by calcareous silty clay loam till.
Depth to groundwater is 1 to 3 feet.
Surface Hydrology
Horicon Marsh is located in the headwater
region of the Upper Rock River Watershed
(Figure 6). The marsh occupies a long north-south
trending valley excavated by glacial action, with
steeply rising terrain of the Niagara escarpment to
the east and gently rolling glacial deposits to the
north and west. The Rock River rises less than 30
miles north of the marsh and discharges into the
Mississippi River at Rock Island, Illinois. The
Upper Rock River Watershed drains a total of 266.5
square miles (Wisconsin Wetlands Inventory, 1978-
1979).
The principle source of runoff to the Refuge is
the west branch of the Rock River, which drains a
total of 110 square miles above the Refuge before it
enters the Refuge 2 miles east of the City of
Waupun. The portion of the river within the Refuge
was historically channelized by a main ditch
running along a north-south line that discharges to
a main outlet near the City of Horicon. However, it
has reverted back to a meandering river in all
reaches on the Refuge except the last half-mile.
Other sources of runoff to the Refuge include Plum
Creek and Mill Creek, which enter the marsh from
the west. These two streams and others entering
from the west and northwest drain through gently
rolling agricultural lands and have relatively gentle
gradients ranging from 5 to 10 feet per mile.
Uplands to the east of the Refuge are relatively
steep agricultural lands. The above-mentioned
sources of runoff combine to yield a total drainage
area of approximately 208 square miles above the
main dike outlet (Table 1).
All watersheds in the Upper Rock River Basin
are considered candidates for nonpoint source
pollution control. The Wisconsin Water Quality
Management Program – Areawide Water Quality
Management Plan for the Upper Rock River Basin,
1989 (Plan) outlines 11 management activities that
should be undertaken to reduce water quality
impacts from nonpoint sources. They are:
# Nonpoint source water resource monitoring
needs;
# Reduce cropland erosion in areas likely to be
affecting water quality;
# Reduce bank erosion on adversely impacted
lakes and streams;
# Reduce the water quality impacts of livestock
concentration areas including barnyards,
feedlots, rest areas, and grazed woodlots,
pastures, and streambanks;
# Minimize the water quality impacts of
construction site erosion and runoff;
# Develop and carry out a program to control
erosion along roadsides;
# Minimize the impact of urban stormwater
discharges on lake and stream water quality;
# Reduce the impact of hydrologic modifications
such as stream straightening and dams;
# Give priority for nonpoint source monitoring
and evaluation to priority watersheds and
watersheds being considered for priority
watershed selection;
# Seek additional means of financing nonpoint
source pollution abatement work; and
# Counties in the basin should identify failing
septic systems and require their replacement.
Chapter 3:Refuge Environment
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Figure 6: Location of Rock River Watershed, Horicon NWR
Chapter 3:Refuge Environment
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In the watershed upstream of Horicon Marsh,
erosion and sedimentation associated with
agricultural land uses are an issue for the Refuge
because these sediments are transported
downstream by the Rock River and deposited in the
low-gradient, low-kinetic energy marsh.
Wilderness Review
As part of the CCP process, lands within the leg-islative
boundaries of both Refuges were reviewed
for wilderness suitability. No lands were found suit-able
for designation as Wilderness as defined by the
Wilderness Act of 1964. With the possible exception
of the Main Pool impoundment on Horicon NWR,
the Refuges do not contain 5,000 contiguous road-less
acres, nor do they have any units of sufficient
size to make their preservation practicable as Wil-derness.
Lands acquired for both refuges have been
substantially affected by humans, particularly
through agriculture and transportation infrastruc-ture.
Archeological and Cultural Values
Land in the area of Horicon NWR and Fox River
NWR was important to prehistoric peoples and to
Euro-American settlers. Horicon Marsh has been
an exceptionally rich resource for subsistence cul-tures
since the glaciers left, and this long and heavy
use by prehistoric people is recorded in the numer-ous
archeological sites on and around the marsh.
For Euro-Americans, the marsh and its outlet were
important resources for commercial and light indus-trial
development, and later for commercial and rec-reational
hunting.
The cultures of the prehistoric and early historic
periods at Horicon and Fox River refuges are basi-cally
the same although the Horicon Marsh area
appears to have supported a larger amount of
human use.
An archeological site near the Refuge in Fond du
Lac County shows evidence of people during the
late PaleoIndian period. The PaleoIndian period
extends from 10000 B.C. to about 8000 B.C. and rep-resents
the culture of the earliest known peoples in
Wisconsin. The evidence for these people is usually
associated with mega-fauna (i.e., bison) kill and
butchering sites. Any sites containing evidence of
people from this period would be considered very
important.
Several archeological sites on and near the Ref-uges
contain evidence of people from the next cul-tural
period, known as the Archaic, covering the
period 8000 to 1000 B.C. These people appear to
have been hunters and gatherers, making a seasonal
round of subsistence resource locations. Late in the
period (or early in the next cultural period) these
people began burying their dead in natural mounds
and commenced using pottery. Very little is known
about this long and early culture, so intact sites con-taining
Archaic period material could be very
important. During the altithermal, a hot and dry
period extending from 4700 to 3000 B.C., people
appear to have clustered around the few remaining
(and shrunken) bodies of water such as Horicon
Marsh. But overall, populations grew substantially
as the people exploited increasingly varried habi-tats.
The Woodland period extended from 1000 B.C. to
A.D. 1600. Most archeological sites on and around
the Refuges contain Woodland period components.
Table 1: Watershed Characteristics, Horicon Marsh, Horicon NWR
Tributary Name Gage Number Drainage Area
(Square Miles)
Slope
(Miles)
100-Year
Discharge
(CFS)
Plum Creek - 15.2 10.1 1000
Mill Creek - 21.7 7.4 1400
South Branch Rock River 5-4235 62.8 5.7 3950
West Branch Rock River
T14NR15E
5-4230 41.4 7.5 2630
West Branch Rock River
T12NR15E (Main Dike Outlet)1
- 208 5.0 860.7
1. Discharge is difficult to estimate at the main dike due to the amount of storage at Horicon Marsh. The approximate 100-
year stage is 1929 and is a statistical inference based on 25 years of Refuge stage records.
Chapter 3:Refuge Environment
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
23
The people of this culture are mostly identified by
their burial mounds and by their use of pottery.
Late in the period they began using the bow and
arrow; prior to that time “arrowheads” were spear-points.
Although hunting and gathering continued
with its seasonal round of resource areas, they also
had larger permanent seasonal villages and grew
corn, beans, and squash in gardens.
The Mississippian culture centered in the St.
Louis, Missouri, vicinity, covered the period A.D.
1000 to 1600. Wisconsin was in the northern periph-ery
and just two sites near Horicon Refuge are
reported to contain evidence of this late prehistoric
culture.
European arrival in the Carribean and on the
Atlantic coast introduced Western culture and
resulted in severe disruption of the prehistoric cul-tures
in Wisconsin long before the first European
entered Wisconsin. European-introduced diseases
spread ahead of Caucasian population advances and
decimated the native populations with reports of up
to 90% mortality. Horses and guns made some
tribes powerful and led to westward movements of
eastern tribes. The fur trade with Europeans fur-ther
disrupted native cultures. These and many
other events led to consolidation and disintegration
and relocation of Indian tribes so that identifying
historical tribal antecedents in the archeological
record is almost impossible.
The historic period tribes encountered by Euro-peans
in Wisconsin generally and in the Horicon
Refuge area specifically included the Winnebago
(some of which are known as the Ho-Chunk) as well
as the Potowatomi and Menominee. Other tribes
within Wisconsin that may have visited the Refuge
area include the Ottawa, Huron, Fox, Sauk, Miami,
Mascouten, and Ojibwa. Historic tribal archeologi-cal
sites are located on and near Horicon Refuge.
For the historic period, human activities in each
Refuge area were different.
The first Western culture settlement appears to
have been in the town of Horicon vicinity. Joel
Doolittle built the first cabin in 1845. The first dam
at Horicon Marsh was probably built in 1845,
replaced a year later by a higher dam that raised
the marsh water level by nine feet, and led to fur-ther
settlement and a sawmill, grist mill, blacksmith
shop, stores, and the Horicon Hotel; the owners
removed the dam in 1869. Other towns originating
during this period included Burnett, Waupun, and
Mayville. From the time of the first dam Euro-
Americans manipulated Horicon Marsh water levels
for floating logs downstream to St. Louis and other
places in the 1850s; and farmers drained, ditched,
and plowed the marsh commencing in the 1870s.
Recreational hunting became important in the late
19th and early 20th century as hunting clubs
acquired land and built low head dams and hunting
lodges. In 1930 another dam was built and water
levels elevated for waterfowl habitat, then lowered
for farming. Thus for the past 150 years the Hori-con
Marsh has been subjected to a variety manipu-lations
to support commercial, recreational, and
agricultural activities.
The Fox River was part of one of the most impor-tant
transportation routes, from the Great Lakes to
the Mississippi River and to the Gulf of Mexico, dur-ing
the 17th and 18th centuries. The first steam
boat came up the Fox River in 1851. Nevertheless
the Refuge area was agricultural until acquired by
the FWS. Immediately east of the Refuge is Foun-tain
Lake Farm, the John Muir Farmstead, that is
listed on the National Register of Historic Places.
The two Refuges have 16 completed cultural
resources (archeological) studies. Based on these
studies and information from the Wisconsin Historic
Preservation Database and other sources, known
and reported cultural resources on the two Refuges
can be summarized.
Social and Economic Context
Most of Horicon NWR is located in Dodge
County, Wisconsin, with a small portion in the north
located in Fond du Lac County, Wisconsin. Table 2
presents social and economic indicators of these two
counties in comparison with the State of Wisconsin
as a whole.
Otter tracks, Horicon NWR
Chapter 3:Refuge Environment
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
24
Both Dodge and Fond du Lac counties are
characterized by a mixture of rural and urban
areas, that is, small towns and villages surrounded
by predominantly agricultural countryside. The
population densities of both counties roughly mirror
that of Wisconsin as a whole (98 and 135 vs. 99
persons per square mile, respectively), while the
State of Wisconsin has slightly less population
density than the USA as a whole (99 vs. 80).
However, the USA’s figure is somewhat distorted
by large, thinly populated Alaska.
In 1990, 39 percent of Dodge County was
classified by the Census Bureau as rural, and 61
percent urban (USFWS, 1995). In the same year,
Fond du Lac County was 35 percent rural and 65
percent urban.
The populations of both counties are growing
relatively slowly at the present time, that is,
growing more slowly than the state as well as the
nation. Dodge County’s population grew by 2.5
percent from 2000 to 2004, and by 12.2 percent in
the 1990s, while Fond du Lac County’s population
grew by 1.4 percent from 2000-2004 and 8 percent
from 1990-2000.
Both counties have lower percentages of
minorities than the state as a whole and the country
at large, which is very typical of the more rural,
northern states. Likewise, there are lower
percentages of foreign born and persons who speak
languages other than English at home.
Educational attainment is lower in both Dodge
and Fond du Lac counties than in Wisconsin
overall, with much lower percentages of college
graduates in the two counties than in the state.
However, this is very representative of rural areas
around the country and is a reflection of the labor
market and kinds of jobs available in rural vs. urban
areas. In spite of having fewer college graduates in
Table 2: Socioeconomic Characteristics Dodge and Fond du Lac Counties, Wisconsin
Characteristic Dodge County Fond du Lac
County
Wisconsin
Population, 2004 estimate 88,057 98,663 5,509,026
Population, % change, 2000-2004 2.5% 1.4% 2.7%
Population, 2000 85,897 97,296 5,363,675
Population, % change, 1990-2000 12.2% 8.0% 9.6%
Land Area, 2000 (square miles) 882 723 54,310
Persons per square mile (population density),
2000
97.4 134.6 98.8
White persons, %, 2000 95.3% 96.2 88.9%
Non-Hispanic white persons, %, 2000 93.8% 95.1% 87.3%
Black or African American persons, %, 2000 2.5% 0.9% 5.7%
American Indian persons, %, 2000 0.4% 0.4% 0.9%
Asian persons, %, 2000 0.3% 0.9% 1.7%
Persons of Latino or Hispanic origin, %, 2000 2.5% 2.0% 3.6%
Language other than English spoken at home,
%, 2000
4.6% 4.8% 7.3%
Foreign born persons, %, 2000 1.6% 2.0% 3.6%
High school graduates, % of persons age 25+,
2000
82.3% 84.2% 85.1%
Bachelor’s degree or higher, % of persons
25+, 2000
13.2% 16.9% 22.4%
Persons with a disability, age 5+, 2000 11,344 12,799 790,917
Median household income, 1999 $45,190 $45,578 $43,791
Per capita money income, 1999 $19,574 $20,022 $21,271
Persons below poverty, %, 1999 5.3% 5.8% 8.7%
Sources: USCB, 2005a; USCB, 2005b; USCB, 2005c
Chapter 3:Refuge Environment
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their midst, the median household incomes of both
counties exceed the state’s median household
income, which is unusual for areas without large
towns or cities.
It is of note that both counties have more than
10,000 residents with at least one disability, which
underscores the importance of Horicon NWR
having accessible facilities.
Several geographic features are important to the
local economy. Mineral resources are extracted and
sold, the high quality soil contributes to the success
of agriculture, and the climate affords opportunities
for many economic activities and causes limitations
for others. The surrounding landscape consists of
gently rolling hills, flat agricultural land, drained
and cropped wetlands, and patches of deciduous
forest. Upland sites are dominated by agriculture,
especially dairy farming, and contain nine
communities with populations from approximately
200 to more than 8,000 people. Little of the native
forest cover remains in the two-county area. The
main forest species are oak, elm, maple, and other
hardwoods. There is limited economic potential
from the remaining woodlots since they tend to be
small and widely scattered. Many contain
residential development and some are located on
public lands (USFWS, 1995).
Table 3 shows the area of land by land-use class
for Dodge and Fond du Lac Counties.
Table 4 on page 26 and Table 5 on page 27
provide employment and industry data for Dodge
and Fond du Lac counties.
The relatively small portion of the overall
workforce in the two counties directly involved in
farming and agriculture belies the importance of
farming in the landscape economy of the two
counties. In Dodge County for example, agriculture
includes hundreds of family-owned farms, related
businesses and industries that provide equipment,
services and other products farmers need to
process, market and deliver food and fiber to
consumers. The production, sales and processing of
farm products generates employment, economic
activity, income and tax revenue in the county
(UWE, 2004a).
The University of Wisconsin estimates that
agriculture provides 9,508 jobs in Dodge County –
almost 20 percent of Dodge County’s workforce of
48,463 people. These jobs are quite diverse,
including farm owners, on-farm employees,
veterinarians, crop and livestock consultants, feed
and fuel suppliers, food processors, farm machinery
manufacturers and dealers, barn builders and
agricultural lenders. Every job in agriculture
generates an additional 0.9 job in Dodge County
due to the multiplier effect. In addition, agriculture
generates over $1.4 billion in economic activity,
accounting for about 28 percent of Dodge County’s
total economic activity. Moreover, every dollar of
sales of agricultural products generates an
additional $0.39 of economic activity in other parts
of the Dodge County economy (UWE, 2004a).
Several mining operations are located in the
general vicinity of Horicon NWR. Products include
limestone, stone, sand, and gravel. Markets for
these products tend to be limited by the distance to
which it is economically feasible to transport the
desired materials. The majority of the materials
mined are used for local road construction and
maintenance projects, other construction activities,
and concrete manufacturing. Employment in this
industry has remained small, but has grown in
recent years (USFWS, 1995).
As the tables indicate, manufacturing is the
largest source of employment in the Horicon NWR
area. Products include machinery, metal products,
commercial printing, canned vegetables, automobile
products, dairy products, and chemicals, to name a
few. More than 75 percent of the manufacturing
jobs in Dodge County are in three industries.
Employment in these three industries has
increased faster than the county average, indicating
employment has become more concentrated and
less diverse.
Woodsedge, Horicon NWR
Chapter 3:Refuge Environment
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Horicon NWR was one of the sample refuges
investigated in a national study of the economic
benefits to local communities of national wildlife
refuge visitation (Laughland and Caudill, 1997).
This study found that that in 1995, resident and
non-resident visitors to Horicon NWR spent about
$1.9 million in the Refuge (Table 6). When this
spending had cycled through the economy, the
Refuge had generated $1.53 million in final demand,
$616,000 in employee compensation, and 44 jobs.
Table 3: Area of Land by Land-Use Class For Dodge and Fond du Lac Counties (thousands of
acres)1
County Forest Cropland Pasture Wetland2 Total
Dodge 27.8 438.6 25.2 111.2 581.3
Fond du Lac 35.1 342.9 37.9 69.6 489.5
1. USFWS, 1995; Timber Resources of Wisconsin’s Southeast Survey Unit, USDA, 1983
2. USFWS, 1995; Wisconsin Wetland Inventory
Table 4: Dodge County Employment and Industry Data
Occupation Number Percentage
Employed civilian population 16 years and over 43,197 100.0
Occupation
Management, professional, and related occupations 10,911 25.3
Service occupations 5,979 13.8
Sales and office occupations 9,298 21.5
Farming, fishing, and forestry occupations 660 1.5
Construction, extraction, and maintenance occupations 4,158 9.6
Production, transportation, and material moving occupations 12,191 28.2
Industry
Agriculture, forestry, fishing and hunting, and mining 2,148 5.0
Construction 2,840 6.6
Manufacturing 14,359 33.2
Wholesale trade 1,142 2.6
Retail trade 4,668 10.8
Transportation and warehousing, and utilities 1,584 3.7
Information 792 1.8
Finance, insurance, real estate, and rental and leasing 1,523 3.5
Professional, scientific, management, administrative, and waste
management services
1,691 3.9
Educational, health and social services 6,929 16.0
Arts, entertainment, recreation, accommodation and food services 2,235 5.2
Other services (except public administration) 1,555 3.6
Public administration 1,731 4.0
Class of Worker
Private wage and salary workers 35,568 82.3
Government workers 4,339 10.0
Self-employed workers in own not incorporated business 3,099 7.2
Unpaid family workers 191 0.4
Source: USCB, 2000a
Chapter 3:Refuge Environment
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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The study concluded that Horicon NWR had a
net economic value of $1,840,200. Every dollar of
budget expenditure at the Refuge generated
economic effects of $10.12. While the Refuge is a
small part of the regional economy, Horicon NWR
and the marsh it protects help define the region’s
character and maintain its quality of life, and thus
are important for the promotion of a diverse
regional economy (Laughland and Caudill, 1997).
Table 5: Fond du Lac County Employment and Industry Data
Employed civilian population 16 years and over 51,374 100.0
Occupation
Management, professional, and related occupations 13,526 26.3
Service occupations 7,750 15.1
Sales and office occupations 11,625 22.6
Farming, fishing, and forestry occupations 638 1.2
Construction, extraction, and maintenance occupations 4,837 9.4
Production, transportation, and material moving occupations 12,998 25.3
Industry
Agriculture, forestry, fishing and hunting, and mining 2,148 4.2
Construction 3,325 6.5
Manufacturing 13,935 27.1
Wholesale trade 1,365 2.7
Retail trade 5,863 11.4
Transportation and warehousing, and utilities 2,539 4.9
Information 773 1.5
Finance, insurance, real estate, and rental and leasing 2,120 4.1
Professional, scientific, management, administrative, and waste
management services
2,495 4.9
Educational, health and social services 8,930 17.4
Arts, entertainment, recreation, accommodation and food services 3,250 6.3
Other services (except public administration) 2,307 4.5
Public administration 2,324 4.5
Class of Worker
Private wage and salary workers 42,762 83.2
Government workers 5,483 10.7
Self-employed workers in own not incorporated business 2,949 5.7
Unpaid family workers 180 0.4
Source: USCB, 2000b
Table 6: 1995 Recreation-related Expenditures (1995 $ in thousands) of Visitors to Horicon NWR
Activity Resident Non-resident Total
Non-consumptive $70.8 $1,772.9 $1,843.7
Hunting $11.9 $37.3 $49.2
Fishing $1.5 --- $1.5
Total $84.2 $1,810.2 $1,894.4
Source: Laughland and Caudill, 1997
Chapter 3:Refuge Environment
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
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Natural Resources
Habitats
Horicon NWR includes over 15,500 acres of
marsh and 5,600 acres of associated upland habitat
(Figure 7). Marsh habitat is seasonally to
permanently flooded and dominated by cattail, river
bulrush, common reed grass, sedges, and reed
canary grass. Uplands include near 3,600 acres of
grasslands and 2,000 acres of woodlands (USFWS,
1995).
Of the nearly 16,000 acres of wetlands on the
Refuge, approximately 3,000 acres are seasonally
flooded (Type I) basins, 12,000 acres are deep (Type
IV) freshwater marshes, and 1,000 acres are sub-impoundments.
Roughly half of the Refuge consists
of dense stands of cattails, either in solid stand or
mixed with other species. Other species include
soft-stemmed bulrush, hard-stemmed bulrush,
slender bulrush, river bulrush, burreed, various
sedges, smartweeds, chufas, pigweeds, millets, and
sagittaria. There are approximately 2,000 acres of
moist soil plants found in and around the edges of
the water areas during drawdown condition. These
include chufas, smartweeds, pigweeds, etc. About
half of the aquatic areas consist of fairly deep lakes,
ditches, and other water areas in which stands of
submersed aquatics are found. These include
various pondweeds, coontail, elodea, duckweeds,
and milfoil (USFWS, 1995).
Grasslands consist of approximately 57 percent
introduced grasslands, 24 percent forbs, 17 percent
are native grasslands, and 3 percent are wet
meadows. Woodlands are willow-dominated (55
percent), mixed hardwoods (22 percent), aspen-dominated
(12 percent), willow-cattail (8 percent),
and oak savanna (3 percent). From these figures, it
is evident that almost two-thirds (63 percent) of the
Refuge’s woodlands are lowland or bottomland and
a little more than one-third (37 percent) are upland
woodlands.
Resource management at the Refuge involves
using a variety of techniques to preserve and
enhance habitats for wildlife, with programs both in
marsh and upland management. Marsh
management involves the manipulation of water
levels to achieve a desired succession of wetland
plant communities to meet the seasonal needs of
wildlife populations. Upland management includes
establishing and maintaining grasslands to provide
nesting habitat for ducks, Sandhill Cranes, and
various song birds. Management objectives include
waterfowl production and migratory bird use, with
Redhead ducks being emphasized.
Wildlife
Waterfowl
Horicon Marsh is a major migratory stop-over
point for waterfowl (ducks, geese, and swans) of the
Mississippi Flyway, with use-days reaching six to
12 million annually. Waterfowl production averages
about 3,000 ducklings per year.
The marsh annually attracts Mississippi Valley
Population (MVP) Canada Geese during their
travels between Hudson Bay and southern Illinois/
western Kentucky (Table 7). The geese are on the
marsh from late February to mid-April and from
mid-September until freeze-up, with peak numbers
in mid-October. The marsh is an important staging
area which fuels their journey north and furnishes
energy for reproduction.
Up to 1 million Canada Geese migrate through
the Refuge each fall. On a peak fall day, there could
be as many as 300,000 geese in the area. Most of
the Canada Geese that stop at Horicon Marsh fly to
their winter range in the area where the Ohio River
Table 7: Mississippi Valley Canada Goose
Population Estimates (1948-1990)
Year Horicon Marsh Mississippi Valley
Population
1948 2,000 170,000
1958 51,000 214,000
1974 214,000 304,000
1984 121,000 477,000
1987 236,000 725,000
1990 199,000 1,300,000 Canada Goose, Horicon NWR
Chapter 3:Refuge Environment
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
29
Figure 7: Current Landcover of Horicon NWR (2006 Classification)
Chapter 3:Refuge Environment
Horicon and Fox River National Wildlife Refuges / Draft Comprehensive Conservation Plan
30
joins the Mississippi River, about 450 miles away.
The rest of the Mississippi Valley population of
Canada Geese that migrate through Michigan,
Ohio, and Indiana join these birds on the wintering
grounds located in southern Illinois, western
Kentucky, Tennessee, and Missouri. From about
the middle of March until the end of April the birds
pass through Horicon Marsh once more to rest and
fatten up for the flight to the nesting grounds near
Hudson Bay in Canada (USFWS, no date-d).
The geese eat about a half-pound of food per day
per bird when they are at Horicon NWR. They are
grazers – they like soft shoots, leaves, and buds
from meadow plants, grasses, wild rice, and
cultivated crops. Goslings eat many insects as a
supply of protein for rapid body growth. They also
eat grain and other seed crops where they can find
them. When geese are present for long periods of
time in extremely large numbers they can cause a
severe problem for some land owners. Geese will
feed on the very same crops farmers in east-central
Wisconsin grow – corn, alfalfa, and winter wheat.
Assistance to farmers is provided by the U.S.
Department of Agriculture and the State of
Wisconsin through a program that charges a surtax
on hunting licenses. The surtax is used to partially
pay land owners for damage caused by geese. This
program is administered by county governments.
Mallards are the principle species of ducks using
the area, but Green-winged and Blue-winged Teal,
American Wigeon, Redheads, Northern Pintails,
Gadwalls, Wood Ducks, scaup, and Ruddy Ducks
are also abundant, with peak duck numbers
traditionally reaching 60,000. The marsh is
especially important to Redhead Ducks, which have
experienced a population decline nationwide. The
marsh is the largest nesting area for Redhead
Ducks east of the Mississippi River, with estimated
2,000-3,000 birds using the marsh for this purpose.
Historically, a majority of the continent’s
Canvasback population used the region during
nesting or migration (Kahl, 1985).
Marsh Birds
For centuries, marsh birds in particular have
descended upon food-rich wetland stopover sites
during their annual migration between Central and
South America and their northern U.S., Canadian
and Arctic breeding grounds. Horicon Marsh has
provided an important link in their journey.
Common marsh and water birds on the Refuge
include the Pied-billed Grebe, American Bittern,
Great Blue Herons, Black-crowned Night Herons,
Great Egrets, Common Gallinule, Sora and Virginia
Rails, and Sandhill Cranes. Tremendous numbers
of shorebirds use low water pools with counts of a
single species typically numbering over 5,000
(USFWS, 1995).
Other Birds
Horicon NWR has documented 267 species of
birds on the Refuge (see Appendix C for a complete
list), including resident, migratory, and accidental
species (USFWS, no date-e). Of the 267 species
recorded on the Refuge, 223 are expected to be
present while 44 birds are listed as “accidental,”
meaning they are not normally expected to be
present. Many birds are present for less than all
four seasons, and they may be abundant, common,
uncommon, or rare.
Although most famous as a fall stopover for
hundreds of thousands of interior Canada Geese,
the vitality and versatility of the marsh is much
better represented by the diversity of birds that use
the Refuge and the marsh. An equal number of
birds use the marsh in the spring as in fall, and
some species are partial to grassland or upland
habitats.
Mammals
The marsh supports an array of resident
mammals including white-tailed deer, woodchucks,
red fox, squirrels, raccoons, muskrat, skunk, mink,
otter, opossum, and coyote. Mammals tend to be
most abundant in and around the wetland habitat
due to the abundant food and cover available.
Muskrats play an important role in striking a
balance between the stands of cattail and the open
water zones.
Upland mammals of Horicon NWR, and their
abundance (abundant, common, or uncommon),
include the following:
# Opossum – common
# Eastern Cottontail Rabbit – common
# Meadow Vole – abundant
# Field mice – abundant
# 13-Lined Ground Squirrel – common
# Eastern Chipmunk – common
# Eastern Gray Squirrel – common
# Fox Squirrel – uncommon
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# Woodchuck – common
# Little Brown Bat – common
# Big Brown Bat – common
# Striped Skunk – common
# Red Fox – common
# Coyote – common
# White-tailed Deer – common
# Raccoon – abundant
Lowland mammals at Horicon NWR include the
following:
# Muskrat – abundant
# Beaver – uncommon
# River Otter – uncommon
# Mink – common
Fish
At one time Horicon Marsh supported a
population of game fish that included northern pike,
crappie, bluegill, and bass. However, due to habitat
degradation associated with turbidity and filling in
of the marsh, game fish populations have
dramatically declined.
Carp populations have become a serious problem
in the marsh due to their high number, aquatic
plant diet, and habit of markedly increasing water
turbidity during feeding. Carp are extremely
prolific, spawning semi-annually, with females
producing as many as 60,000 eggs per pound of fish.
They retard the growth of aquatic vegetation by
consuming it and by roiling the water so that
increased turbidity reduces photosynthetic
efficiency which is essential for wetland food chains.
Current management strategies at controlling carp
include physical removal, water level manipulation,
chemical eradication, and stocking of predators,
especially northern pike (USFWS, 1995).
Amphibians and Reptiles
Amphibians and reptiles are two natural and
distinct classes of vertebrates common to the area.
Several species of turtles and snakes are found in
the area. Salamanders, newts, toads, and frogs
depend on quality wetland habitat for their survival.
Amphibians recorded at Horicon NWR include
the following:
# Western Chorus Frog – uncommon
# Leopard Frog – common
# American Toad – abundant
# Spring Peeper
# Eastern Gray Treefrog
# Bullfrog
# Green Frog
# Wood Frog
# Tiger Salamander
Reptiles recorded at Horicon NWR include the
following:
# Painted Turtle – common
# Snapping Turtle – common
# Red-Bellied Snake – common
# Garter Snake – common
# Milk Snake – rare
Threatened and Endangered Species
At present, the only Federally-listed threatened
or endangered wildlife species that uses the marsh
is the Bald Eagle. Bald Eagles were placed on the
Federal Endangered Species list in 1973, and are
protected by both state and federal laws. Since
Wisconsin’s eagle population was higher and more
stable than that of most other states, the federal
government listed the state’s eagles as "threatened"
in 1978. In 1991, 414 active Bald Eagle territories
were located, exceeding the recovery goal of 360.
The formerly listed Peregrine Falcon has also
been observed at Horicon NWR (listed as “rare” in
spring, fall, and winter), but in a conservation
success story, it was de-listed in 1999 due to
continent-wide improvements in the status of
peregrine populations, from 324 breeding pairs in
1975 to 2,000-3,000 breeding pairs by the late 1990s
(USFWS, no date-f).
Snapping turtle, Horicon NWR
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State-listed endangered species at Horicon NWR
include the Osprey, Forster’s Tern, and Barn Owl.
Migratory Bird Conservation Initiatives
Several migratory bird conservation plans have
been published over the last decade that can be
used to help guide management decisions for the
refuges. Bird conservation planning efforts have
evolved from a largely local, site-based orientation
to a more regional, even inter-continental,
landscape-oriented perspective. Several trans-national
migratory bird conservation initiatives
have emerged to help guide the planning and
implementation process. The regional plans
relevant to Horicon NWR and Fox River NWR are:
# The Upper Mississippi River/Great Lakes Joint
Venture Implementation Plan of the North
American Waterfowl Management Plan;
# The Partners in Flight Boreal Hardwood
Transition [land] Bird Conservation Plan;
# The Upper Mississippi Valley/Great Lakes
Regional Shorebird Conservation Plan; and
# The Upper Mississippi Valley/Great Lakes
Regional Waterbird Conservation Plan.
All four conservation plans will be integrated
under the umbrella of the North American Bird
Conservation Initiative (NABCI) in the Prairie
Potholes, Eastern Tallgrass and Prairie Hardwood
Transition Bird Conservation Regions (BCR 11, 22
and 23). Each of the bird conservation initiatives
has a process for designating priority species,
modeled to a large extent on the Partners in Flight
method of computing scores based on independent
assessments of global relative abundance, breeding
and wintering distribution, vulnerability to threats,
area importance, and population trend. These
scores are often used by agencies in developing lists
of priority bird species. The Service based its 2001
list of Non-game Birds of Conservation Concern
primarily on the Partners in Flight, shorebird, and
waterbird status assessment scores.
Wildlife Species of Management
Concern
Appendix G summarizes information on the
status and current habitat use of important wildlife
species found on lands administered by Horicon
NWR. Individual species, or species groups, were
chosen because they are listed as Regional
Resource Conservation Priorities or State-listed
threatened or endangered species. Other species
are listed due to their importance for economic or
recreational reasons, because the Refuge or its
partners monitor or survey them, or for their status
as a nuisance or invasive species.
Horicon NWR Current Refuge
Programs: Where We Are
Today
Consistent with its authorizing legislation, Hori-con
NWR conducts a broad array of wildlife man-agement
activities on the Refuge. Horicon NWR’s
Master Plan, completed in 1978, developed a list of
planned activities consistent with the purpose of the
Refuge:
# Waterfowl Production – Diver and dabbler
ducks
# Waterfowl Maintenance – Diver and dabbler
ducks, geese
# Environmental Preservation
# Special Recognition Species – marsh birds,
shorebirds, and raptors
# Threatened Species Maintenance – Bald Eagle,
Osprey, Cormorant
# Wildlife/Wildlands Observation
# Wildlife Trails (non-motorized)
# Tour Routes (motorized)
# Interpretive Center
# Interpretive Exhibits/Demonstrations
# Environmental Education
Great Egret, Horicon NWR
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# Hunting – Migratory waterfowl, coot, big game,
upland game
# Fishing
In the quarter-century since publication of the
Master Plan, Refuge management has made signifi-cant
progress in implementing these planned activi-ties
and products. Refuge planning and
management, however, are a continual work in pro-cess
that evolves over time depending on feedback
and monitoring as well as changing values, needs,
and priorities in wildlife management at the Refuge,
regional, and national scale. Hence the value of a
new plan – this CCP – which updates and modifies
Horicon NWR’s management emphasis.
This section summarizes current management
programs, operations, and facilities at Horicon
NWR. It also describes the participation and coop-eration
of Refuge staff and management activities
with our partnering agencies and stakeholders in
the wider community on efforts to balance compet-ing
demands for natural resources, wildlife, and pro-tection
from environmental hazards like flooding.
Habitat Restoration
Many of the current management efforts on the
Refuge focus on restoring valuable wildlife habitats
that have declined regionally since the advent of
intensive habitat modification and destruction
wrought by Euro-American settlement, agricultural
development and drainage projects. Horicon NWR
staff carries out wetland and upland habitat restora-tion
projects on the Refuge.
Habitat Restoration on the Refuge
Habitat restoration efforts at Horicon NWR
focus on both upland and wetland habitats. Within
the last year, upland habitat restoration has focused
on improving the quality and quantity of oak
savanna habitats. Brush and other tree species have
choked out oak savanna habitat. Several methods
are used to remove the brush and other trees to
allow for the resurgence of oaks. Refuge staff issue
firewood-cutting permits to remove larger trees
that have encroached on the historic oak savannah
openings. Staff and contractors will also remove
larger trees. Staff will use specialized equipment to
mow brushy areas to reclaim the grass component
of the oak savannah habitat. Staff will also be exper-imenting
with particularly hot prescribed burns as a
means of restoring and maintaining oak savanna.
Efforts are also under way to restore native prai-rie
grasslands on the Refuge. Restoration typically
involves treatment of degraded grasslands, those
that have become dominated by non-native, inva-sive,
or woody species like willows. Fields with non-native
or invasive species are sprayed with the her-bicides
Round-Up and 2-4D. The area is then
burned to provide good seed-to-ground contact. The
seed mix includes 21 forb species and five grass spe-cies,
all Wisconsin Genotype. The seedings are usu-ally
initiated in late fall or early winter, dependant
on a light snow cover. A seed blower attached to the
hitch of a vehicle is used to plant the seed. Fields
invaded by small woody vegetation are mowed using
a Fecon mower. Most upland fields on the Refuge
have been invaded and dominated with reed canary
grass, sweet clover or wild parsnip.
Although native to North America, reed canary
grass has hybridized with introduced European
strains to create a highly aggressive and invasive
strain that is spreading at the expense of other
native species. Reed canary grass is flood-tolerant,
resistant to burning, a prolific seed producer,
spreads rapidly through rhizomes, and quickly
forms virtual monocultures in wet meadows by
shading out native grasses and forbs. Control
requires aggressive measures. Horicon NWR is
experimenting with using grazing as a tool to reduce
Black-eyed Susan, Horicon NWR
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the amount of reed canary grass. This is a form of
adaptive management, and in the spirit of adaptive
management, we are always experimenting with dif-ferent
methods to enhance native grasslands.
Managed impoundments give opportunities to
restore wetland habitat to more desirable condi-tions.
Currently, a project is under way removing
the functionality of ditches in the Main Pool of the
Refuge. By creating long ditch plugs in several
areas of the ditch, staff are trying to reestablish
sheet flow of water and prevent ground and surface
water flow from being transported down the
ditches.
Habitat Management
As our knowledge and understanding of wildlife
ecology evolves over time, and as circumstances and
values “on the ground” change, the direction of wild-life
management tends to change as well. Two exam-ples
of changing philosophies and approaches are
evident at Horicon NWR and many other national
wildlife refuges, with regard to the “edge effect”
and the value of diverse warm season seed mix for
wildlife. The conventional wisdom among wildlife
managers in the late 1970s and early 1980s was that
it was valuable to maximize edges between different
vegetation communities. The justification was that
since wildlife species that depend on one or the
other, or both, of two adjoining habitats could occur
near the edge between the two habitats, these edges
tend to have higher species diversity than locations
set deep within any one habitat type. Thus, increas-ing
the length of edges was deemed desirable.
Twenty-five years later, however, as more infor-mation
became available from long-term studies,
biologists now believe that the advance of civiliza-tion
has whittled away large contiguous blocks of
habitat, and the species that depend on them are in
jeopardy. Biological diversity is best served by
reducing fragmentation and increasing the areas of
habitat blocks, as well as by increasing the connec-tivity
between blocks of similar habitat, so that
organisms may move along these corridors and
maintain genetic fitness and variability, and thus
population viability.
Similarly, for decades wildlife biologists (particu-larly
waterfowl managers) encouraged the planting
of dense nesting cover for waterfowl nesting. This
method of seeding planted a very thick stand of
warm season grass, usually only one or two species
with little forb diversity. However, by the late 1990s,
wildlife biologists generally and the U.S. Fish and
Wildlife Service specifically were adopting more
holistic approaches to wildlife management. They
realized that these planting were too thick for nest-ing
and that waterfowl preferred a diverse struc-ture
of forbs and grasses for nesting.
In recent years, the management philosophy at
Horicon NWR, paralleling that of other refuges
around the country, has become more oriented
toward fostering or simulating natural processes
(like wildland fire) to achieve desired landscapes
and to restore scarce habitats that were prevalent
prior to Euro-American settlement in the region.
Given the highly manipulated environments in
which Horicon NWR and most other refuges occur,
this often means actively intervening in natural
plant community succession and hydrologic pro-cesses
rather than passively allowing nature to “run
its course.” In order for the Refuge to effectively
pursue its purpose and meet the expectations of the
American public, Refuge staff actively manage the
various habitats through a variety of techniques and
procedures discussed in the following paragraphs.
Managing Water Impoundments and Moist Soil
Units
Horicon NWR’s water management program is
very complex and involves 17 impoundments
(Figure 8). Pools are frozen for about 4 months of
the year, from December to April. During periods of
“ice-out,” May to November, water management not
only must balance competing considerations of wild-life
and habitats on the Refuge itself, but it must
deal with the requests of off-Refuge neighbors
downstream as well as other township, county,
state, watershed, and flood control agencies. Regu-lating
water levels – whether at maximum pool lev-els
or in drawdown (emptying pools almost entirely
of water) – is a vital management tool for waterfowl,
shorebirds, and wading birds. Over the years, water
management has been further complicated by
increased land clearing and development on private
lands upstream of the Refuge, which increase nutri-ent
and sediment transport onto the Refuge. Within
the last 2 years, the Refuge has experienced severe
flooding, which results in rapid pool level increase,
or “bounce,” of 2 to 3 feet. Bounces during the
breeding season negatively affect nesting efforts of
many species. For instance, the flood that began in
May of 2004 essentially wiped out a production year
for many species. Managers must be cognizant of
conditions throughout the watershed, exercise good
judgment, and at times be willing to deviate tempo-
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Figure 8: Impoundments, Horicon NWR
Black-eyed Susan, Horicon NWR
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rarily from Refuge objectives when downstream cit-ies
and towns are experiencing extreme flooding
events.
Horicon NWR’s Marsh and Water Management
Plan (1993) guides management of the Refuge’s
marshes, open water, water levels and discharges.
The plan states that production and maintenance of
waterfowl are the primary objectives at Horicon
NWR, and that to fully achieve these objectives, a
diversity of habitats must be provided to meet the
life history requirements of waterfowl for nesting,
brood rearing, and migration. The presence or
absence of water, its depth, and the seasonal timing
of water depth fluctuations are all manipulated to
produce various stages of marsh habitats on which
different water-dependent birds rely.
An annual marsh and water management plan is
written every winter. This plan summarizes opera-tions
during the previous year, describes major
water management problems, and documents con-struction
and rehabilitation projects. It also identi-fies
proposed pool elevations for the upcoming years
along with stated objectives for each management
unit. Ma