Excerpts from Iowa's Comprehensive Wildlife Conservation Strategy (CWCS) applicable to Private Landowners.

QUICK LINKS TO SECTIONS OF THIS DOCUMENT:
The State of Iowa's Natural Communities

• Topography and Climate
• Geology
• Publicly-owned Conservation Lands

Wildlife Conservation

• Wildlife Restoration
• Land Acquisition
• Habitat on Private Lands Lands

Iowa's Natural Communities Today

A Vision for Iowa's Wildlife in 2030

Iowa's Species of Greatest Conservation Need

• Key to Symbols
• Breeding birds
• Migratory birds
• Mammals
• Reptiles and Amphibians
• Fish

THE STATE OF IOWA'S NATURAL COMMUNITIES
Topography. Iowa is a state of 56,239 square miles bordered by the Mississippi River on the east, and the Missouri and Big Sioux Rivers on the west. Iowa has a relatively low relief - elevations run from a high of 1,670 feet above mean sea level in Osceola County in northwestern Iowa to 480 feet above mean sea level in Lee County in the southeastern corner of the state.

Climate. Iowa's climate is classified as humid continental and is characterized by warm summers and cold winters. A small portion of northern and northeastern Iowa are in the cool - summer subtype (Hillaker 1993). The average temperature in the summer ranges from 71 degrees F in the north to 73 degrees in the south part of the state. December to February winter temperatures average 22 degrees with an average winter difference of 6.5 degrees between north and south. Temperature minimums of -25 degrees F are not uncommon in northern Iowa.

Statewide winter snowfall averages 32 inches. Northern Iowa (north of U.S. Highway 30) receives frequent snow often associated with strong winds, blowing and drifting. Southern Iowa may experience substantial snowfall as well as more frequent ice storms. This results in a snow cover that is often covered by a surface crust of ice or hard snow. Harsh conditions seldom last for more than a few weeks in most of the state, even less in the south half.

The average annual precipitation is 32 inches. The northwest part of the state is the driest with an annual precipitation of 28 inches while the southeast is the wettest with an annual precipitation of 36 inches. Iowa often experiences seasonal extremes and frequent local, rapid weather changes due to the convergence of cold, dry Arctic air, moist maritime air from the Gulf of Mexico, and dry Pacific air masses. Like most states, periods of severe drought and periods of excessive precipitation can have a dramatic impact on terrestrial and aquatic vegetation as well as their associated fish and wildlife species.

These climatic factors combine to influence the length of the growing season across the state. Late frosts in the spring and early freezes in the fall result in a reduced growing season of 135 days in northeastern and northwestern Iowa. The longest growing season is in southeastern Iowa, with an average of 175 days. The state average growing season is 158 days long.

Geology. Iowa's natural communities are as much a result of its recent geologic past as they are a result of climatic conditions (Prior 1991). Prior (1991) divides the state into seven geologic regions based on the underlying bedrock as well as the location of glacial and loess deposits. (Map 2-1). The boundaries of these landform regions coincide well with the boundaries of other habitat based classification systems. The underlined names for regions are those listed in Prior (1991). The names in parentheses are habitat-based names for the landforms that describe the native vegetation that was present at the time of settlement. Descriptions are taken from Prior (1991) and Iowa GAP.

The Loess Hills (Tallgrass Prairie) is a unique landform that formed at the end of the last Ice Age about 18,000 years ago. The formation is only one to fifteen miles wide but is about 200 miles long extending from near Sioux City, Iowa to St. Joseph, Missouri. Although deposits of windblown soils (loess) are found in many parts of the world, nowhere else but in China do they reach as high as in Iowa where some of the hills are more than 200 feet above the adjacent Missouri River valley. The Loess Hills landform has other features that are easily noticed. Bedrock is exposed naturally in only a few places and the soil has unique physical properties. If the topsoil on the slope of a hill is removed, the exposed loess will erode quickly and deep gullies will form. Even when covered with topsoil, loess can slump, often in a unified way across a slope creating “cat-step” ledges along the sides of hills. However, when a loess hill is cut vertically the exposed wall will stand for decades.

The Des Moines Lobe (Prairie Potholes) has a landscape that is gently rolling with abundant moraines, shallow wetland basins or potholes, and a few relatively deep natural lakes. This landform still retains the imprints of recent glacial occupation. Loess is entirely absent. The most prominent landform patterns left by the Wisconsin glacier on the Des Moines Lobe are the end moraines. The Des Moines Lobe is part of the Prairie Pothole Region that extends north and west into western Minnesota, eastern North and South Dakota, and the Canadian Prairie Provinces. Most of the potholes have been drained with ditching and underground tile lines to make way for agriculture. Agriculture was also responsible for greatly increasing the rate at which streams and drainage patterns developed in this geologically young landform.

The Southern Iowa Drift Plain (Tallgrass Prairie) is the largest of Iowa’s landforms. Like the Des Moines Lobe, it is composed almost entirely of glacial drift, but the Pre-Illinoisan glaciers that deposited material in this part of Iowa were much older. As a result, deep glacial drift, ranging from a few to several hundred meters, is the only evidence of their occupation. Instead of poorly drained and relatively level landscapes, streams have had time to erode the land surface and form well-defined drainage systems. Hilltops have similar elevations that reveal the approximate level of the land surface constructed by the last ice sheet. As erosion slowly dissected this landscape, a layer of loess ranging from 2 to 10 meters was deposited over the glacial till. Throughout the Southern Iowa Drift Plain the terrain varies considerably, but the pattern of relief resulting from its history of erosion is the dominant feature of the region. Many of the larger rivers had glaciers standing in their headwaters at the time the Des Moines Lobe was ice-covered. These valleys obtained much of their present width, depth, and alluvial fill from flooding as the Wisconsin ice sheet melted away from northcentral Iowa. In many places the rivers have cut through the glacial drift into the underlying sedimentary bedrock. The rough wooded terrain adjoining these valleys supports many scenic and recreational areas and important wildlife habitat.

The Iowan Surface (Eastern Tallgrass Prairie) landform extends over a large region of northeastern Iowa and is characterized by long, gently rolling slopes, low relief, and open views of the horizon. Pre-settlement vegetation in this region was primarily prairie with heavily wooded floodplains along the larger watercourses. Drainage networks are well developed, but stream gradients are low with some scattered areas of poor drainage and natural wetlands. The area was once part of the Pre-Illinoisan Southern Iowa Drift Plain but experienced large-scale and more destructive erosion events, the latest occurring during the coldest part of the Wisconsin glaciation 16,500 to 21,000 years ago. Frost action, down slope movement of water-soaked soil materials, and strong winds were the dominant geologic processes in this region. Layers of loess are thin and scattered. Glacial boulders are numerous and many are very large. Elongated ridges and isolated oblong hills called pahas occur in the southern part of the Iowa Surface region. These features are covered with a mantle of silt and sand believed to have accumulated in response to strong northwesterly winds that occurred during the period of glacial cold. Soils mapped on the larger pahas indicate they developed under forest vegetation rather than prairie. Karst topography occurs in the northern part of the landform where cavities in the underlying limestone bedrock collapsed and formed sinkholes. Fens are also present but more scattered than in the Des Moines Lobe.

The Northwest Iowa Plain (Eastern Tallgrass Prairie) contains many of the terrain features and geologic materials present in other landforms and is similar in appearance to the Iowa Surface with a uniform low relief. This landform was and still is a relatively treeless, gently rolling landscape. Despite these similarities, the landscape differs from other regions because of a combination of factors. The western uplands of this region are underlain with highly eroded, Pre- Illinoisan glacial tills. The eastern part of these tills is covered with later glacial deposits from an early Wisconsin glacial advance. The entire region was then subjected to vigorous erosion activity that accompanied the later advance of the Wisconsin ice sheet. As a result, features of a freshly glaciated landscape were lost as a well-established branching network of streams formed over the entire region. The deeper thickness of the loess mantle, the overall elevation of the land surface, and the present precipitation and vegetation distinguish the Northwest Iowa Plains from the state’s other landforms. Windblown loess is abundant and nearly continuous across the region ranging in thickness from 4 to 16 feet. Altitudes throughout the Northwest Iowa Plains are uniformly higher than any other portion of the state and topographically are continuous with the High Plains of the Dakotas. Average annual precipitation is lower than other parts of the state. Thus, the region is higher, drier and less timbered than any other in the state. Although bedrock exposures are rare in the Northwest Iowa Plains, the oldest bedrock in Iowa (Precambrian-age Sioux Quartzite) occurs here along the Big Sioux River.

The Paleozoic Plateau (Prairie to Hardwood Transition) is the most distinctive of Iowa’s landforms because of its abundant rock outcroppings, karst topography, a near absence of glacial deposits, many deep narrow valleys, cool-water streams, and heavily wooded uplands. Numerous gorges and ravines cause abrupt local changes in the direction of slopes and exposures. These sites provide abundant cool, moist and wooded habitats rich in diverse communities of plants and animals. Seeps and springs are common features along valley sides where strata of varying permeability are exposed and signify subterranean drainage systems. Ice caves and cold-air (algific) slopes are unique to this area. Unusual microclimates associated with these features support a particularly rare and sensitive biological habitat in Iowa. The steep rocky slopes are unsuited for agriculture and remain heavily forested. Remnant prairies occur on south and west facing slopes. Ecologists believe these prairies were more extensive before the suppression of naturally occurring fires following European settlement.

Alluvial Plains, often called floodplains, are constructed by water flowing off of the landscape and carrying with it boulders, cobbles, gravel, sand, silt, and clay. This process of erosion creates a dendritic-shaped landform of nearly level corridors with varying widths depending on the size and reach of the river. These corridors are largest along the Missouri and Mississippi Rivers but can be found along streams throughout the other landforms. The floodplain is a dynamic landform that is frequently disturbed, sometimes drastically, by flood and drought events. Stream channels may be cut off leaving backwater sloughs or oxbow lakes. Large-scale vertical changes may also occur within the floodplain due to the deposition of alluvium that forms terraces and benches. These structures are level but are elevated above existing floodplains by a distinct slope. Smaller tributaries that enter the floodplain of a larger river often form alluvial fans that may cover older floodplain materials. During low flow periods, wind becomes an important factor in the transport of materials. Exposed sand or soil having little or no vegetation to hold it place can be blown onto floodplain and terraces as well as onto higher elevations along valley margins. Sand dune topography occurs downwind of valley floors.

The glacial history and topography of each landform affect the type and distribution of current wildlife habitats and agricultural land use.



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WILDLIFE CONSERVATION
Wildlife Restoration. Not all wildlife trends of the past half-century have been negative. The creation of the Iowa State Conservation Commission (now IDNR) in 1935, the gradual development of wildlife science and management as professions after World War II, and the formation of IDNR's Wildlife Diversity Program in 1981 have returned a portion of Iowa’s native wildlife to the state. White-tailed deer, wild turkeys and giant Canada geese are now more abundant than at any time since the late 1800’s. Other restoration programs have returned ruffed grouse to southern Iowa, river otters to the state's streams, peregrine falcons, ospreys and trumpeter swans nest again in Iowa. Bald eagles, bobcats and Sandhill cranes have reappeared as a result of successful conservation programs elsewhere. Details of these and other wildlife restoration programs are explained in Trends in Iowa Wildlife Populations and Harvest - 2004.







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Land acquisition. IDNR has also pursued land acquisition programs to permanently protect and enhance wildlife habitat. Since 1972 Iowa waterfowlers have been required to purchase an Iowa Migratory Game Bird Stamp. Since 1979 all hunters have been required to purchase a Habitat Stamp along with their hunting license. Proceeds from these stamps are dedicated to habitat protection and management. Funds from the Habitat Stamp are shared equally with Iowa's 99 County Conservation Boards.

IDNR has aggressively sought funds for habitat protection through the North American Waterfowl Management Plan, the North American Wetlands Conservation Act, State Wildlife Grants, the Environmental Protection Agency, Iowa County Conservation Boards and others. IDNR also partners with a number of NGOs to extend the reach of state and Federal funds. Ducks Unlimited, Pheasants Forever, National Wild Turkey Federation, Iowa Natural Heritage Foundation and The Nature Conservancy have been major cooperators with IDNR's habitat protection programs. Numerous other NGO's and individual private contributor have helped as well.

Since 1980 IDNR has acquired 100,000 acres of land to enhance or restore habitat for wildlife. Research sponsored by IDNR has found that these restored lands are colonized quickly by birds that utilize the appropriate habitats as they develop. Little is known about responses from less-mobile wildlife like amphibians and reptiles.

In spite of the aggressive efforts to protect wildlife habitat, Iowa remains one of the states with the highest proportion of privately held land (Map 2-2). Public conservation lands accounted for just over 600,000 acres in 2004, or just 1.7% of the land area of the state (Iowa GAP).

The IDNR owns nearly half of the public conservation lands (322,00 acres), including state parks, state forests and wildlife management areas. Federal ownership accounts for 138,000 acres in four flood control reservoirs, 5 national wildlife refuges and 57,000 acres of WRP easements. IDNR has land management agreements on portions of the reservoirs but little control over water levels. County Conservation Boards own 134,000 acres.

Habitat on private lands. Wildlife habitats on private lands have also received attention from IDNR programs. Farm Game Habitat crews roamed the state in the 1950's and 1960's helping landowners establish habitat on their property. In 1971 the number of IDNR wildlife management biologists was doubled and they were housed in USDA farm service center offices to promote contacts with private landowners. In the 1980's farmstead shelterbelts and switchgrass cost-sharing programs were introduced to promote these practices on private land. For the past 20 years IDNR biologists have actively promoted USDA farm bill practices (e.g. CRP, WRP) that provide landowners funds to assist with developing wildlife t. The Wildlife Bureau's Private lands Program was formed in 2002 to take better advantage of wildlife-friendly USDA farm programs and other Federal grants like the LIP.

The success of private lands assistance programs has been mixed. Wildlife habitat has been affected on 65,000 acres. In the past, however, private land habitats have disappeared when land ownership or landowner objectives change or as government subsidies for habitat protection have ended. Some of the new programs (WRP, LIP) require permanent easements and habitat improvements will remain. Others are short term and will likely revert to more financially rewarding uses when government programs end.













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IOWA'S NATURAL COMMUNITIES TODAY
The result of a century and a half of change as a result of human intervention on Iowa’s landscape has been a shift in the composition of Iowa’s plant communities and the wildlife that inhabits them. Few undisturbed natural plant or wildlife communities exist today. Less than 0.1% of Iowa's native prairies (30,000 acres), 5% of its wetlands (422,000 acres), and 43% of its forests (2,800,000 acres) remain.

Of these, forestlands are the only habitats that are increasing on private lands without state or Federal intervention. The shift from raising livestock on the farm to confinement operations has reduced the need for pasture in the past decade and a half. Today Iowa has nearly 1 million acres of pastureland reverting to early successional forest, most in the Southern Iowa Drift Plain, the Paleozoic Plateau and the Loess Hills.

The majority of the state is covered with row crop, primarily corn and soybeans. Most of the remainder of the state is in grassland, often conservation reserve, road ditches or pasture, with lesser acreages of timber and other habitat types.

A VISION FOR IOWA’S WILDLIFE IN THE YEAR 2030
Few Iowans are aware that their state was once a land of unparalleled wildlife abundance and diversity. Early settlers discovered, however, that underneath Iowa’s prairies lay the finest farmland in the world. In less than a century the prairies were plowed and with them went flocks of prairie chicken, herds of bison and elk and the cougars, grey wolves, black bear and bobcat that preyed on them. Wetlands were drained and flocks of waterfowl numbering in the millions that nested here were diminished to a tiny fraction of their former numbers. Most of the forests were cleared, the white-tailed deer and wild turkey disappeared and once-uncountable flocks of passenger pigeons became extinct. Plowing freed the prairie soil to run into once-clear waters and game fish like brook trout, longear sunfish and grass pickerel disappeared. Once a wilderness, Iowa had become home to a multitude of small family farms. Only small animals like the bobwhite quail, rabbits, squirrels and the soon-to-be-introduced ringnecked pheasant thrived.

The 20th century brought its own changes driven by the constant improvement in farming technology. Ever-larger and more powerful farm equipment; the introduction of herbicides, pesticides, plant hybrids and genetically modified crops; and Federal farm programs that have rewarded all-out production eventually made much of the state unsuitable for even farm-adapted wildlife. Numbers of bobwhite quail and jackrabbits have plummeted, pheasants are in a half-century decline and songbirds of our forests and grasslands are declining rapidly. Nearly a third of Iowa’s lakes, rivers and streams are considered imperiled waters.

Wildlife conservation programs have returned adaptable wildlife like deer and wild turkey to our forests, Canada geese and Trumpeter swans to our wetlands, bald eagles and peregrine falcons to our skies, and river otters to our streams. Land conservation efforts have restored thousands of acres of grasslands, wetlands and forest. Farm programs have placed hundreds of thousands of acres of temporary conservation practices on private land.

But after a half-century of conservation, one-third of all of Iowa’s fish and wildlife are considered in need of immediate conservation to stop their numbers from eventually dwindling into threatened or endangered status. A host of less-visible and specialized wildlife – songbirds, lizards and snakes, frogs and salamanders, fish, freshwater mussels and highly-fragile butterflies among others - is seriously threatened by the disappearance and degradation of their habitats. Iowa has less than 2 percent of its landscape in permanently protected wildlife habitat and managed under conservation practices. The remainder is privately held and subject to the whims of landowners as they respond to economic and social pressures. The pace of conservation efforts has not been able to keep up with the wholesale habitat destruction of the past century that still continues today. Without assistance to reverse these trends, more species will face a grim future – eventual disappearance from our state.

Iowa is farming country
Barring an environmental or economic collapse of global proportions, Iowa will remain one of the world’s great agricultural regions. The highest and best use of most of this landscape is in agricultural production. Nothing in this Plan suggests returning Iowa to its pre-settlement state on any but a small part of the land. The challenge for Iowans is to find a way to protect our remaining wildlife heritage and preserve a legacy for our heirs by creating viable and sociallyacceptable wildlife environments within a landscape dominated by agriculture.

A Vision for the Future
To establish a focus for future wildlife conservation activities, the Advisory Committee to the Iowa Wildlife Action Plan – a group of fish and wildlife professionals, educators, researchers, private conservation organizations, concerned citizens and representatives of the agricultural community - developed a vision for the status of Iowa's wildlife in 25 years. The vision statement has 6 elements that include benefits to fish and wildlife, the citizens who enjoy and support them, and the private landowners who must embrace them if the vision is to be realized. With each vision element the Advisory Committee developed specific conservation actions that need to be implemented to reach the Plan’s goals in a 25-year framework.

These vision elements and conservation actions are not specifically designed to be implemented by IDNR. They are designed to provide a broad framework of actions that can be undertaken by conservationists at all levels of government, by private conservation organizations and by private citizens. Extensive coordination will be necessary between these stakeholders to make the vision a reality.

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IOWA'S SPECIES OF GREATEST CONSERVATION NEED
Species of greatest conservation need are those animals, both aquatic and terrestrial, that are at risk or are declining in Iowa. They include threatened and endangered species, as well as many other species whose populations are of concern in our State.

Key to the symbols:

Iowa Abundance:

• A = abundant
• C = common
• CL = common locally
• U=uncommon
• UL = uncommon locally
• R = rare
• SC = special concern
• Th = threatened
• En = endangered
• X = extirpated
• E = extinct

Iowa Trend:

• D = decreasing
• I = increasing
• S = stable
• K = unknown

Iowa Status:

• B =breeding
• N = non-breeding

State and National Status:

• NX,SX - Presumed Extirpated—Species or community is believed to be extirpated from the nation or state/province. Not located despite intensive searches of historical sites and other appropriate habitat, and virtually no likelihood that it will be rediscovered.



• NH,SH - Possibly Extirpated (Historical)—Species or community occurred historically in the nation or state/province, and there is some possibility that it may be rediscovered. Its presence may not have been verified in the past 20-40 years. A species or community could become NH or SH without such a 20-40 year delay if the only known occurrences in a nation or state/province were destroyed or if it had been extensively and unsuccessfully looked for. The NH or SH rank is reserved for species or communities for which some effort has been made to relocate occurrences, rather than simply using this status for all elements not known from verified extant occurrences.



• N1,S1 - Critically Imperiled—Critically imperiled in the nation or state/province because of extreme rarity (often 5 or fewer occurrences) or because of some factor(s) such as very steep declines making it especially vulnerable to extirpation from the state/province.



• N2,S2 - Imperiled—Imperiled in the nation or state/province because of rarity due to very restricted range, very few populations (often 20 or fewer), steep declines, or other factors making it very vulnerable to extirpation from the nation or state/province.



• N3,S3 - Vulnerable—Vulnerable in the nation or state/province due to a restricted range, relatively few populations (often 80 or fewer), recent and widespread declines, or other factors making it vulnerable to extirpation.



• N4,S4 - Apparently Secure—Uncommon but not rare; some cause for long-term concern due to declines or other factors.



• N5,S5 - Secure—Common, widespread, and abundant in the nation or state/province.



• NNR,SNR - Unranked—Nation or state/province conservation status not yet assessed.



• NU,SU - Unrankable—Currently unrankable due to lack of information or due to substantially conflicting information about status or trends.



• NNA,SNA - Not Applicable —A conservation status rank is not applicable because the species is not a suitable target for conservation activities.



• N#N#,S#S# - Range Rank —A numeric range rank (e.g., S2S3) is used to indicate any range of uncertainty about the status of the species or community. Ranges cannot skip more than one rank (e.g., SU is used rather than S1S4).



• Not Provided - Species is known to occur in this nation or state/province. Contact the relevant natural heritage program for assigned conservation status.

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Breeding birds of greatest conservation need

Migratory birds of greatest conservation need

Mammals of greatest conservation need

Reptiles and amphibians of greatest conservation need

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Fish of greatest conservation need

Percent of Iowa species in each taxonomic class listed as a SGCN

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