Iowa is located in the heart of the Midwest, defined by the Missouri River on its western border and the Mississippi River on the east. This position, flanked by two major river systems, contributes significantly to the state’s biological diversity. The landscape is primarily fertile plains, but also features pockets of deciduous forests along river valleys and remnants of historic tallgrass prairie. These varied ecosystems support a wide array of wildlife.
Iowa’s Key Terrestrial Mammals
The White-tailed Deer (Odocoileus virginianus) is the most numerous large land mammal in Iowa, thriving in the state’s mix of agricultural fields and fragmented woodlands. These adaptable herbivores use dense cover for shelter and abundant crops for forage, allowing their population to flourish statewide. Their numbers rebounded significantly in the 20th century following conservation efforts.
The Coyote (Canis latrans) is a widespread terrestrial mammal, found in every county and across all habitat types, from rural farmland to urban edges. These opportunistic predators have a diet that shifts seasonally to include small rodents, rabbits, deer fawns, insects, and fruits. Their adaptability has enabled them to flourish despite human development and intensive agriculture.
Raccoons (Procyon lotor) are common nocturnal residents, recognized by their black mask and ringed tail, and are typically found near water sources and forested areas. They are omnivores that exploit diverse food sources, including acorns, crayfish, insects, and human refuse, often nesting in tree hollows or abandoned structures. Squirrels are also frequently observed, including the larger Fox Squirrel (Sciurus niger) and the Eastern Gray Squirrel (Sciurus carolinensis) in forests and urban parks.
The American Badger (Taxidea taxus) is a carnivore associated primarily with the open country and grasslands of western Iowa, though it can be found statewide. Badgers are fossorial, meaning they are specialized for digging, and they create extensive burrows to hunt ground squirrels, pocket gophers, and other subterranean rodents. Their presence indicates remnant prairie and grassland habitats that provide the necessary soil conditions.
The State’s Rich Avian Population
Iowa’s position along the Mississippi Flyway, a major north-south migration corridor, makes it a temporary home for hundreds of migratory bird species each spring and fall. The state also hosts numerous permanent residents, contributing to a rich avian community. The American Goldfinch (Spinus tristis), Iowa’s official state bird, is a small, bright yellow finch easily spotted in fields and backyard gardens.
The Ring-necked Pheasant (Phasianus colchicus) is the most popular upland game bird, introduced and now established in grasslands and row-crop fields across much of Iowa. This species prefers undisturbed cover for nesting and winter survival, making conservation practices that preserve grassy field edges important. The Wild Turkey (Meleagris gallopavo) has also seen a successful reintroduction, now populating the state’s woodlands and river corridors.
Raptors are well-represented, with the Red-tailed Hawk (Buteo jamaicensis) commonly seen soaring over open fields or perched on utility poles while hunting small rodents. Waterfowl, including various species of ducks and geese, rely on the numerous wetlands and the expansive Mississippi and Missouri Rivers during migration. The state’s waterways provide essential resting and refueling stops.
Herpetofauna and Aquatic Inhabitants
Iowa’s herpetofauna, encompassing reptiles and amphibians, finds refuge in the state’s diverse aquatic and moist environments. Common reptiles include the Painted Turtle (Chrysemys picta), frequently seen basking on logs in ponds and slow-moving waters. The Common Garter Snake (Thamnophis sirtalis) is the most widespread snake species, often found in gardens, fields, and near water, feeding on earthworms and amphibians.
The state has two venomous snake species: the Timber Rattlesnake (Crotalus horridus) and the Copperhead (Agkistrodon contortrix). The Timber Rattlesnake is confined to rocky, forested bluffs in the eastern and southern parts of the state. The Copperhead’s range is restricted to the southernmost counties. Amphibians, such as the Tiger Salamander (Ambystoma tigrinum) and various species of frogs, require aquatic habitats for breeding, utilizing natural wetlands and man-made farm ponds.
The aquatic environments of Iowa’s rivers, lakes, and reservoirs support a robust fish population. The Channel Catfish (Ictalurus punctatus) is a common species in the major rivers, known for its ability to tolerate a range of water conditions. Anglers frequently target Largemouth Bass (Micropterus salmoides) and Smallmouth Bass (Micropterus dolomieu), found in lakes and cooler streams, respectively.