Wild About Birds - Illinois Raptors!

Kingdom: Animalia - Animals are multicellular organisms that rely on other organisms for nourishment. There cells do not have cell walls. Most animals are capable of movement at least in some portion of their life cycle. Reproduction is generally sexual, but in some animals asexual reproduction may be utilized at certain times.
Phylum: Chordata - The Phylum Chordata contains the vertebrate animals. Mammals, birds, reptiles, amphibians and fishes are included in this phylum. These animals have a notochord at some point in their development. They have a tubular nerve cord along the back. Gill slits and a tail are present at some point in their life cycle. They have an internal skeleton.
Class: Aves - Birds are the only organisms with feathers. They are endotherms, maintaining a nearly constant body temperature. They have a hard bill but no teeth. A gizzard, which functions to grind food, is present in the digestive tract. Fertilization is internal. A nest is built in which the hard-shelled eggs are deposited and incubated.
Order: Accipitriformes (buteos, accipiters, ospreys, eagles, harriers, kites)
Family: Pandionidae (ospreys)
     osprey (Pandion haliaetus) [state threatened]

Family: Accipitridae (buteos, accipiters, eagles, harriers, kites)
     Mississippi kite (Ictinia mississippiensis)
     bald eagle (Haliaeetus leucocephalus)
     northern harrier (Circus hudsonius) [state endangered]
     sharp-shinned hawk (Accipiter striatus)
     Cooper’s hawk (Accipiter cooperii)
     northern goshawk (Accipiter gentilis)
     red-shouldered hawk (Buteo lineatus)
     broad-winged hawk (Buteo platypterus)
     Swainson’s hawk (Buteo swainsoni) [state endangered]
     red-tailed hawk (Buteo jamaicensis)
     rough-legged hawk (Buteo lagopus)
     golden eagle (Aquila chrysaetos)

Order: Falconiformes (falcons)
Family: Falconidae
     American kestrel (Falco sparverius)
     merlin (Falco columbarius)
     gyrfalcon (Falco rusticolus)*
     peregrine falcon Falco peregrinus
     prairie falcon (Falco mexicanus)*

Order: Strigiformes (owls)
Family: Tytonidae
     barn owl Tyto alba

Family: Strigidae
     eastern screech-owl Megascops asio
     great horned owl Bubo virginianus
     snowy owl Bubo scandiacus
     burrowing owl (Athene cunicularia)*
     barred owl Strix varia
     long-eared owl Asio otus
     short-eared owl Asio flammeus [state endangered]
     northern saw-whet owl Aegolius acadicus

* Species not represented on poster.

​buteos - These large hawks fly on wide, slow-beating wings that allow them to soar and search for prey. They perch on tree limbs, fence posts, telephone poles and similar items.

Illinois species:
red-shouldered hawk, broad-winged hawk, Swainson’s hawk, red-tailed hawk, rough-legged hawk

 

accipiters - The true hawks have a long tail (like a rudder) and short, rounded wings. When flying, they make several quick wing beats and then glide. True hawks are aggressive and very quick.

Illinois species:
sharp-shinned hawk, Cooper’s hawk, northern goshawk

 

 

ospreys – These birds can be recognized by their wings that appear to be “bent” or “angled” as they fly. Found near large bodies of water, they dive feet-first to catch fishes.

Illinois species: osprey

 

falcons – Falcons have long, thin, pointed wings, a short bill and a streamlined body. They can fly very fast.

Illinois species: American kestrel, merlin, peregrine falcon

 

eagles – Eagles are larger than hawks and have longer wings. Their bill is almost as long as their head.

Illinois species: bald eagle, golden eagle

 

harriers – Harriers fly close to the ground and hold their wings in a “v” shape during flight. These birds have a long, thin body with long, rounded wings and long legs. The tail is long. Male and female harriers are distinguishable by their feather coloration.

Illinois species: northern harrier

kites – These medium-sized hawks have pointed wings. Their hooked beak helps them to feed on their prey items.

Illinois species: Mississippi kite

 

owls – Owls have fringed outer wing feathers for silent flight. Their wings are rounded, and the tail is short. These birds can turn their heads around 270 degrees.

Illinois species: barn owl, eastern screech-owl, great horned owl, snowy owl, barred owl, long-eared owl, short-eared owl, northern saw-whet owl

​Raptors have a variety of features that help them to survive.

​Birds of prey have ear openings on each side of the head behind and beneath the eyes. The ears are usually covered with feathers. Owls and harriers have a facial disk (round face) that helps funnel sound to the ears.

​A talon, or claw, can be found at the tip of each of the eight toes. Talons are made of keratin and are extremely sharp. The downward-curved shape, sharpness and length of each talon make it difficult for raptors to walk. Strong leg muscles and toes along with the talons provide the weaponry needed to capture food. Some raptors can crush their prey’s vertebrae with their toes.

​Raptors have the best vision in the animal kingdom. Their eyes are placed in the front of the head, giving them a wide field of vision and binocular vision. The eyes of these birds are so large that they cannot move within the eye socket. In order to see to the side, they must turn their head. The long, flexible neck allows for them to turn the head almost backwards. Owls cannot see in total darkness but are capable of vision in very dim light. The retina of their eye has structures that are very sensitive to light but not to color. The pupil in each owl’s eye functions independently, an advantage when hunting in areas of varied light and shadow.

​A bird’s beak is made of bone and covered with keratin. In birds of prey, the tip of the beak is hooked, and the edges are sharp. The hooked beak is used to tear meat into pieces that can be easily swallowed. A falcon’s upper beak is notched and is used to break the neck vertebrae of its prey. Raptors have a soft fleshy area, called the cere, at the base of the upper bill. The cere is featherless and helps these meat-eating birds keep the area around the bill clean.

​Owls eat their prey whole or in large chunks. They cannot digest everything that they swallow. “Pellet” is the term for the bones, hair, shells and other items that the owl coughs up. These parts cannot pass easily through the owl’s digestive tract. To get rid of them, the owl removes them through its mouth.

​Owls make almost no sound when they fly. Silent flight is a great assistance to catching prey. Owl wings are very large for their body size, and their outer wing feathers are fringed to reduce noise.

​Birds of prey use several nesting strategies. The peregrine falcon does not spend any energy making a nest. It lays its eggs on a high bluff or ledge of a tall building. The eastern screech-owl and American kestrel use a tree cavity or nesting box to place their nest. The males of many raptor species collect sticks, feathers, leaves and mosses that the female uses to construct the nest. Bald eagles may use the same nest year after year, adding more branches, roots and corn stalks each year.

​Raptors face many challenges, with most of them imposed by humans. Degradation and loss of habitat are the main reasons that raptors are endangered and threatened in the state. The picture does not have to be bleak, however. Humans can take positive actions to preserve and improve habitat for these birds to help them survive.

As of 2020, the Illinois Endangered Species Protection Board lists three raptor species as endangered in the state and one species as threatened.

Endangered: short-eared owl Asio flammeus Destruction of grassland and wetland habitats are the main factors related to the small number of individuals of this species in Illinois. Its populations also fluctuate based upon the abundance of the small mammals that it feeds on.

Endangered: Swainson’s hawk Buteo swainsoni In Illinois, this bird is at the eastern limit of its range. It may never have been very abundant in the state, but it was formerly much more widespread than it is today. It lives in open grasslands.

Endangered: northern harrier Circus cyaneus As a breeding bird, this species is rare in the state. It relies on grassland and marsh habitats, and much of those areas have been destroyed in Illinois. The northern harrier does migrate through Illinois and is a common winter resident.

Threatened: osprey Pandion haliaetus The osprey’s population was affected adversely in the mid-twentieth century by the extensive use of pesticides. It has recovered well in other parts of the country since the use of many pesticides was banned in the United States, but its population in Illinois has not rebounded quickly.

​More information about Illinois raptors is available from the Illinois Department of Natural Resources (IDNR). The Division of Natural Heritage manages and monitors bird populations. Natural Heritage personnel also provide assistance to landowners regarding establishing and maintaining raptor habitat. The IDNR Division of Education provides supplemental resources for educators to use, including the Masters of the Air activity book, Illinois Birds resources trunk that is available for loan from more than 70 lending locations statewide and several other resources available on our Web site. Wood Projects for Illinois Wildlife is an IDNR booklet that includes plans for nesting boxes that are used by some raptors. Publications are available through the publications page. The Illinois Audubon Society’s mission is to promote the perpetuation and appreciation of the native flora and fauna of Illinois and the habitats that support them. Fundamental to this end are the control of pollution, the conservation of energy and all natural resources, a sound ecological relationship between human populations and their environments and the education and involvement of the public in such efforts.