Archive - December 2018
osprey Pandion halieatus
What is an Osprey?
An osprey is a bird. Specifically, it is a raptor. Birds are warm-blooded animals with feathers, hard-shelled eggs and lightweight bones. Because they are warm-blooded, birds can maintain a constant internal body temperature and be active when their natural environment has extremes of very warm or very cold conditions. Feathers are used for flight, protection and attraction of a mate.
They also aid in controlling body temperature and in helping birds to identify other birds. Birds lay hard-shelled eggs. The hard shell, made mostly of calcium carbonate, keeps the egg from drying out and allows parents to sit on the eggs during incubation. Lightweight bones are necessary for flight. Bird bones are strong and have internal braces. Many bird bones are filled with air and are connected to the respiratory system. Other bones are fused together, increasing their strength. Raptors have large eyes that face forward. They have a hooked beak and sharp talons.
What Does It Look Like?
The body feathers on the back and sides are black or dark brown. The belly feathers are white. The head feathers are mainly white with some areas of black patches and a dark line that includes each eye. Wing feathers have a black tip. There is a wide black band on the underside of the tail with a thin, white line at the tip of the tail.
How Big Is It?
An adult osprey is about 21 to 24 inches long and has a wingspan of 54 to 72 inches. It weighs about two to five pounds.
Where Does It Live?
Some ospreys migrate through Illinois, but others nest along large rivers and lakes in our state. These birds spend the winter from the southern United States as far south as Chile in South America.
How Does It Reproduce?
Ospreys mate for life, but they may not breed every year. When they do breed, there is one clutch of two to four eggs produced per year. The male brings food for the female from the time of courtship through the time that the young birds have left the nest. He also defends her during this period. Courtship includes an elaborate flight display.
What Does It Eat?
Fishes are the main prey item, but amphibians, birds and crayfish are also eaten.
Does Anything Eat It?
This bird is a top predator in the food chain. The only organisms that feed on it are scavengers and decomposers after it dies.
What Else Should I Know About It?
- The osprey plunges feet first into water to catch fishes.
- A distinct “bend” in the wings can be seen when the bird flies.
- The nest of dead limbs is placed high in a tree or on a platform in standing water.
- Ospreys have bristly pads on their feet to help them grip slick fishes. When they carry a fish with their feet while flying, they line up the fish’s head with their own head to cut wind resistance.
- A reversible outer toe allows them to have two toes pointing forward and two toes pointing backward on each foot.
Can I Hunt It?
NO! The osprey is endangered in Illinois.