Archive - February 2022

What is a mammal? It's an animal with four limbs (legs/arms). It has hair or fur. It is warm-blooded. That means its body temperature is kept at the same level instead of being controlled by the environment. Most female mammals bear young that develop in a special organ, the uterus. Two species of mammals lay eggs, but they do not live in Illinois. After birth, mammal young are fed with milk produced by the female's mammary glands. Mammals have a large and complex brain.

There are 63 species of wild mammals in Illinois.

Order Didelphimorphia (American Marsupials)

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia (Mammals) - Mammals are warm-blooded. Most mammals have young born after developing inside the mother's body in a special organ called a uterus. After birth, the young are fed with milk produced in the female’s mammary glands. A mammal has a large and complex brain.
Order: Didelphimorphia (Opossums) - The opossum bears young that are not fully developed. After birth these tiny opossums crawl into a pouch on the female’s body to complete their development.
Family: Didelphidae (American Opossums and Opossums) - The young are born immature and develop within the mother's pouch on her belly. Each didelphid has 50 teeth. The toe on the inside of each back foot is opposable (able to grasp objects and aid in climbing) and has no claw. The tail is prehensile and has scales.
Virginia opossum (Didelphis virginiana)

Order Cingulata (Armadillos)

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order Cingulata: (Armadillos) - Armadillos have bony plates in the skin that covers the top, sides, head and tail of the body. They are land-based and primarily eat insects.
Family: Dasypodidae (Armadillos) - Armadillos have a bony armor under a leathery skin that covers the upper body. Most species have the armor in shields over the hip and shoulder regions with bands of armor separated by flexible skin on the back and sides. There is an armor covering on the head, too, and on the tail. The teeth are simple in structure. There are no incisors or canines. The diet is mainly composed of insects and other small invertebrates.
nine-banded armadillo (Dasypus novemcinctus)

Order Eulipotyphla (Insectivores)

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Eulipotyphla (Shrews and Moles) - Shrews and moles are small mammals that feed mainly on insects. They have a long, flexible snout and thick fur. Their eyes and ears are very small or not present. Shrews are active at night and are very ferocious for their small size. Moles spend most of their life in soil, using their large front feet and claws to dig tunnels as they search for insect larvae and other prey.
Family: Soricidae (Shrews) - Shrews have five toes per foot. Their eyes and ears are very small. The snout has whiskers at the tip and is long and flexible. Their fur is thick and short. North American shrews have red tips on their teeth. The first incisor on each side of the upper jaw is notched. Their metabolic rate is very high.
masked or cinereus shrew (Sorex cinereus)
southeastern shrew (Sorex longirostris)
American pygmy shrew (Sorex hoyi)
northern short-tailed shrew (Blarina brevicauda)
southern short-tailed shrew (Blarina carolinensis)
North American least shrew (Cryptotis parva)

Family: Talpidae (Moles) - The mole lives most of its life below the surface of the ground. Its front feet are larger and wider than its back feet and are modified for digging. The eyes are tiny or absent, and there are no external ears. The nose is long and flexible.
eastern mole (Scalopus aquaticus)

Order Chiroptera (Bats)

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Chiroptera (Bats) - Bats are the only true-flying mammals. Their hands are modified into wings. They use echolocation to find food, but small eyes are present, and they can see well. The tragus at the base of the ear assists in hearing.
Family Vespertilionidae: (Evening Bats and Vesper Bats) - A prominent tragus (a piece of skin that extends into the middle of the ear) is present in all of these bats. There is no leaflike flap on the nose. They eat insects. Some bats that live in Illinois in the summer migrate out of the state in the winter, while other bats hibernate. Illinois’ female bats undergo delayed fertilization. They mate in fall and store sperm in their uterus until ovulation occurs after the female exits hibernation.
     eastern red bat (Lasiurus borealis)
     hoary bat (Aeorestes cinereus)
     Rafinesque's big-eared bat (Corynorhinus rafinesquii) [state endangered]
     silver-haired bat (Lasionycteris noctivagans)
     big brown bat (Eptesicus fuscus)
     tri-colored bat (Perimyotis subflavus)
     evening bat (Nycticeius humeralis)
     gray bat (Myotis grisescens) [state and federally endangered]
     southeastern bat (Myotis austroriparius) [state endangered]
     northern long-eared bat (Myotis septentrionalis) [state and federally threatened]
     eastern small-footed bat (Myotis leibii) [state threatened]
     little brown bat (Myotis lucifugus)
     Indiana bat (Myotis sodalis) [state and federally endangered]

Order Lagomorpha (Hares and Rabbits)

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Lagomorpha (Hares and Rabbits) - This group includes the rabbits and hares, mammals with a short, furry tail. Rabbits have long legs and long ears. A distinctive trait is their four incisors (front teeth) on the upper jaw.
Family: Leporidae (Hares and Rabbits) - Members of this family are medium-sized and have long legs, long ears and a short, furry tail.
swamp rabbit (Sylvilagus aquaticus)
eastern cottontail (Sylvilagus floridanus)

Order Rodentia (Rodents)

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia (Rodents) - Rodents are small- to medium-sized mammals. They have incisors that grow continually throughout their life and must be worn down by gnawing on hard materials. Rodents have a large gap between their incisors and the rest of their teeth. This order contains the largest group of mammals in Illinois.
Family Sciuridae: (Squirrels) - Squirrels are medium-sized, mostly diurnal (active in the daytime) mammals. There are four toes on each front foot and five toes on each back foot. The tail is hairy. Some squirrels are arboreal (tree-dwellers), and some live on the ground.
eastern chipmunk (Tamias striatus)
woodchuck (Marmota monax)
thirteen-lined ground squirrel (Spermophilus tridecemlineatus)
Franklin's ground squirrel (Poliocitellus franklinii) [Illinois threatened]
eastern gray squirrel (Sciurus carolinensis)
eastern fox squirrel (Sciurus niger)
red squirrel (Tamiasciurus hudsonicus)
southern flying squirrel (Glaucomys volans)

Family Geomyidae: (Pocket Gophers) - The mammals in this family are adapted for living in soil. They do not have a distinct neck but do have short, strong legs. There are five toes on both the front and hind feet, and each of them has a claw. The claws on the front feet are large and use for digging. The eyes, ears and tail are small. The lips can be closed behind the incisors. They have fur-lined cheek pouches that are used for transporting food.
plains pocket gopher (Geomys bursarius)

Family Castoridae: (Beavers) - The beaver is a large rodent. It is well-adapted for its aquatic lifestyle. The ears and nose have valves that close while under water. The tail is enlarged and flattened. The back feet are webbed. The lips shut behind the incisors. Anal scent glands are used to mark territorial boundaries.
American beaver (Castor canadensis)

Family Cricetidae: (New World Rats and Mice, Voles, Hamsters and Relatives) - Cricetidae is one of the largest families of mammals, and there is much diversity in its members, so it is difficult to make a general description. Most of them are small with an elongated body. The fur is gray or brown with lighter or white hair on the belly and chin. The tail is long, and the eyes are large. The ears are easily seen. Whiskers are present.
marsh rice rat (Oryzomys palustris)
western harvest mouse (Reithrodontomys megalotis)
deer mouse (Peromyscus maniculatus)
white-footed mouse (Peromyscus leucopus)
cotton mouse (Peromyscus gossypinus)
golden mouse (Ochrotomys nuttalli)
eastern woodrat (Neotoma floridana)
meadow vole (Microtus pennsylvanicus)
prairie vole (Microtus ochrogaster)
woodland vole (Microtus pinetorum)
muskrat (Ondatra zibethicus)
southern bog lemming (Synaptomys cooperi)

Family Muridae: (Old World Mice and Rats, Whistling Rats, Gerbils and Relatives) - Old World rats and mice are small- to medium-sized rodents. Most have four toes on the front feet, and all have five toes on the rear feet. All have 16 teeth, four for gnawing and 12 for grinding.
brown rat (Rattus norvegicus) [nonnative]
house mouse (Mus musculus) [nonnative]

Family Dipodidae: Jerboas, Jumping Mice and Birch Mice - This family includes the jerboas, jumping mice and birch mice, of which only one species of jumping mouse is found in Illinois. They are small- to medium-sized rodents that are adapted for jumping. Most are omnivores that eat insects and seeds.
meadow jumping mouse (Zapus hudsonius)

Order Carnivora (Carnivores)

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora (Carnivores) - These mammals feed primarily on prey that they capture. They are large- to medium-sized mammals with claws on their feet.
Family: Canidae (Coyotes, Dogs, Foxes, Jackals and Wolves) - Coyotes, wolves and foxes have elongated legs. They have five toes on each front foot and four toes on each back foot. Their ears stand up straight. The snout is long and narrow. They communicate by barking or howling.
     coyote (Canis latrans)
     red fox (Vulpes vulpes)
     gray fox (Urocyon cinereoargenteus)

Family: Procyonidae (Coatis, Raccoons and Relatives) - The raccoon has a long tail with alternating color bands. There are five elongated toes on each of the front and back feet.
raccoon (Procyon lotor)

Family: Mustelidae (Badgers, Otters, Weasels and Relatives) - Weasels, minks, badgers and otters are a varied group. Many of them have a long, slender body with short legs. The ears are small and rounded, and the snout is short. Scent glands are present at the base of the tail.
     least weasel (Mustela nivalis)
     long-tailed weasel (Mustela frenata)
     American mink (Neovison vison)
     American badger (Taxidea taxus)
     North American river otter (Lontra canadensis)

Family: Mephitidae (Skunks and Stink Badgers) - Skunks have a black and white color pattern and well-developed anal scent glands. The body is broad, and the snout is long. The tail is furred. They are nocturnal and eat a variety of foods.
striped skunk (Mephitis mephitis)

Family: Felidae (Cats) - A cat has a short face and small ears. It has five toes on each of the front feet and four toes on each of the back feet. The claws are rectangular and retractable. The teeth are adapted for cutting.
bobcat (Lynx rufus)

Order Artiodactyla (Even-toed Ungulates)

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla (Even-Toed Ungulates) - The ungulates group contains the white-tailed deer, a large mammal with long legs and hooves. The stomach of these mammals has four chambers.
Family: Cervidae (Deer) - Members of this family are hoofed mammals. They have antlers (males only) that are shed and replaced every year. The four-chambered stomach is necessary to digest the vegetation that they eat. Deer chew their cud (regurgitated food material from the stomach is chewed and swallowed again).
white-tailed deer (Odocoileus virginianus)