Wildlife & Habitat
Wildlife in Illinois
Illinois is home to some 58 mammal species, 383 different resident and migrant birds, 104 types of reptiles and amphibians, 174 species of fish, and some 27,000 types of insects, mussels, and other invertebrates. And, at nearly 400 miles long, Illinois hosts tremendous biological diversity, from the Iowa Pleistocene snail in the northwest, to bird-voiced treefrogs in 1,000-year-old cypress swamps in the south. This vast array of animal species that inhabit Illinois depend, directly or indirectly, on one another—for example, removing any one species may result in disproportionately high numbers of another, as certain species prey on others. Unfortunately, a 2004 study showed that 27% of Illinois flora was non-native. The dominating presence of non-native plants lessens the space available for native plants, thereby diminishing Illinois’s unique, indigenous plant communities. Insects requiring those native plants, and the species that rely on those insects, are also imperiled by the loss of native plant species.

Native habitats are key to our wildlife’s future—unfortunately, habitats in Illinois have changed enormously and many wildlife populations have declined at alarming rates as a result. For example, the size of woodlands in Illinois act as a limiting factor on some native species’ populations, making the protection of larger size woodlands necessary. Moreover, there are cross-benefits to protecting wildlife habitat—flood control, recreation, soil erosion control, and open space.

Moreover, the Illinois economy realizes nearly $1.1 billion every year from expenditures related to watching wildlife and hunters spend nearly $150 million a year pursuing game. More than $550 million is spent each year on recreational fishing, and the annual retail value of commercial fishing is $4 million. This wildlife-oriented recreation plays an important economic role in many depressed and declining small communities.

Habitats of Special Significance
The Great Lakes ecosystem supports a wealth of biological diversity, including many species and communities of global significance. Of the animal/plant species and natural community types identified within the Great Lakes basin, 131 of them are deemed critically imperiled, imperiled, or rare on a global scale. The basin is also home to more than 1/10 of the U.S. population and more than 1/4 of the population of Canada. Nearly 25% of the total Canadian agricultural production and 7% of the U.S. agricultural production occur in the basin. Some of the world’s largest concentrations of industrial capacity are located around the Great Lakes. Some of these human activities adversely impact the basin ecosystem and continue to pose threats to the biological diversity in the basin.

Locks and dams disrupt river habitats by preventing species of fish and mussels from moving along the river, and keeping submersed vegetation from growing—all of which decreases biodiversity. Locks and dams also stop the normal cycle of flooding, a cycle many animals use to access floodplains for nesting and rearing of offspring.

Furthermore, invasive species can disrupt aquatic habitats. For example, silver carp, which were first introduced in the 1970s to help remove algae from catfish farms, have since escaped the farms and migrated up the Mississippi River system. Also known as the flying carp, these fish can grow to 50 or more pounds. The connection between Lake Michigan and the Illinois River acts as a conduit for invasive species—as a result, these fish now threaten to enter the Great Lakes. The carp displace native species of fish by filter feeding and removing the bottom of the food chain for indigenous species.

Current Laws
While there is still much work to be done, there have been several legislative successes in protecting Illinois water so far.
Illinois Wildlife Action Plan:
The Illinois Wildlife Action Plan ensures that our state’s biodiversity and abundance of wildlife is maintained for the long-term by focusing on habitat. The plan covers all forms of wildlife — aquatic, terrestrial, vertebrate, invertebrates, endangered, game, and non-game — and specifically identifies wildlife with declining populations or special needs, and works to conserve those populations rather than waiting for them to become endangered. Plan actions are grouped into seven overlapping campaigns, based on habitat and common issues:

  • Farmland and Prairie – There were once approximately 22 million acres of prairie in Illinois — this has been reduced to about 2,500 acres. Most of the land once occupied by prairie is now farmland, which has resulted in a steep decline of grassland species. This campaign expands and improves grassland, shrub, and wetland habitats in agricultural landscapes.
  • Forest and Woodlands – Poor forest and woodland management and inappropriate timber harvesting have contributed to a changed forest composition and degradation of our remaining forest habitat. This campaign maintains and enhances the composition of our existing forests and increases the distribution of those habitats statewide and in identified priority areas.
  • Green Cities – Urban development has degraded and fragmented our already-limited wildlife habitat. This campaign improves community planning efforts by including open space and wildlife needs into those plans. Additionally, the campaign addresses urban area use in migration routes, and promotes habitat protection and restoration whenever possible.
  • Invasive Species – Invasive species pose one of the greatest threats to Illinois’ natural areas, native communities, and natural resources. Species that are rare or declining are often at greatest risk of invasive species because of their few numbers or inability to adapt to changes in habitat. This campaign identifies actions determined to be most needed for statewide management of invasive species.
    Streams – Agriculture and development have drastically reduced the health of our 26,000 miles of streams and rivers. This campaign identifies focal species and promotes actions that improve habitats and reduces stressors for these species.
  • Wetlands – Wetlands are highly productive environments for plants and animals, but our remaining wetlands have been highly degraded. This campaign protects and improves the functionality of our remaining wetlands, promotes connectivity among wetland complexes with habitat corridors, and reintroduces native species into wetland habitats.
Endangered and Threatened Species in Illinois:
The Illinois Endangered Species Protection Act was passed in 1972, predating the federal Endangered Species Act of 1973. The original version of the Act protected animals but not plants, and only established the category of “Endangered.” Subsequent amendments added a “Threatened” category, included plants, and gave much clearer protections for endangered species and their habitats — indeed, Illinois was among the first states to attempt to protect endangered species’ habitats through legislation. Later amendments provided equal protections for both threatened and endangered animal species, and added provisions for the incidental taking of endangered and threatened species. The Act establishes the Endangered Species Protection Board and the Endangered and Threatened Species program administered by the Department of Natural Resources.

As apex predators are returning to the states, it’s important to update legislation with the goal of protecting these species. In 2014, the cougar, black bear, and grey wolf were added under the regulation of Illinois Department of Natural Resources which gives the department more options regarding their protection.

In addition, all Illinois agencies and local governments are required to consult with DNR whether actions carried out by them are likely to jeopardize the continued existence of Illinois listed endangered and threatened species or are likely to result in the destruction or adverse modification of the designated essential habitat of such species.

In 2017, HB0685 was introduced that prevents counties and municipalities from classifying milkweed, the sole host plant of the threatened Monarch butterfly, as a noxious weed. This bill was proposed by Sierra Club volunteers who noticed the issue in their neighborhoods.

Our Vision for Habitat Conservation in Illinois
Indigenous Illinois species must be protected and, concurrently, protections against invasive species should be tightened.
Genetic biodiversity (variation in genes within a species) and ecological biodiversity (diversity of ecosystems, natural communities, and habitats) are extremely important for providing a greater variety of crops, medicinal resources, and pharmaceutical drugs. Diverse systems also provide ecological services such as cleaning water, absorbing chemicals, providing oxygen, soil formation and protection, and nutrient storage and recycling. Healthy ecosystems and genetic diversity can better withstand and recover from a variety of disasters like fires and floods, and prevents diseases and helps species—including humans—adjust to changes in their environment. Strategies should be enacted that prevent and remove invasive species, including reviewing and updating the exotic/noxious weeds list, and adding new plants as needed.
The Illinois Wildlife Action Plan should be the focal point for establishing species protection goals and should be used as a road map for prioritizing those goals.
Illinois should provide appropriate funding to support programs and staff that protect native Illinois species, such as natural heritage biologists, dedicated staff biologists, and land stewardship and restoration programs. The various campaigns should continue to expand and conserve: woodland habitats, the connecting corridors that link existing, larger pieces of habitat to create pathways for the movement of plants and animals; and, backyard habitats so vital to migratory species such as monarchs and songbirds.
Our aquatic natural resources including wildlife and habitat should be protected.
Healthy ecosystems tend to have many natural checks and balances where every species plays a role in maintaining the system. Loss of diversity generally increases the chance of a system-wide collapse when the system is subjected to even small stressors. Therefore, Illinois law should address habitat loss and species protection by protecting wetlands and discouraging floodplain development. Nutrients from agriculture and toxic chemicals from industry have drained into the watersheds of Illinois, resulting in the loss of some species. To prevent this from continuing, public waters of the state should be expanded to include streams and the state should designate “Outstanding Resource Waters” to protect the best of the best. The Conservation Reserve Enhancement Program should be restored.
Dam removal should be incentivized in smaller streams and the construction of new dams should be blocked except where necessary for the control of aquatic Invasive species.
Illinois has nearly 1400 dams on its rivers and streams, many of which have outlived their usefulness. They threaten the ecology of aquatic ecosystem by degrading water quality and hindering fish passage, while also posing significant safety risks to river recreationists. To mitigate these threats, funding programs for dam removal should be restored, and the construction of new dams should be discouraged.
  • The endangered species consultation requirement should be expanded and the IESA should be fully enforced to protect aquatic endangered species.
Further Reading
Vist the Illinois Wildlife Action Plan website to learn more about the species and places they protect, as well as how you can help!

Partners for Parks and Wildlife

Partners for Parks and Wildlife (PPW) is a grassroots coalition that is dedicated to secure and increase funding for open space and park acquisition, natural area preservation, wildlife habitat protection and recreational opportunities in Illinois.

Learn More About Climate Change

The U.S. EPA’s website on climate change was once a great resource for basic scientific information on the topic and we look forward to the day that it is again. Until then, the City of Chicago is making sure its citizens have access to research and information.


One of the simplest ways to donate to the IEC is by contributing through EarthShare in your workplace charity campaign .