The Osprey  

Ospreys (Pandion haliaetus) are part of the hawk family.  They are large birds with a wingspan that may reach up to 6 feet across.  Ospreys have brown feathers on their backs and on the tops of their wings.  White feathers are predominately found on their heads, belly and legs.   

Methods of hunting
Ospreys are also known as “fish hawks”.  They have earned this name because they almost exclusively feed on fish.  They search for fish by flying over the water and watching the surface below.  When an osprey sees a fish near the surface, it dives steeply towards the water with its talons outspread.  Once it enters the water, it quickly resurfaces with the kill securely held by its feet and talons.  The soles of the osprey’s feet are spiked in order to aid its grip.   

After the osprey becomes airborne again, it will adjust the fish until the fish’s head is pointing in the same direction as the osprey is flying.  It is presumed that this is to reduce drag during flight.    

Bald eagles do not directly prey on ospreys, but they will steal the osprey's food.  The larger eagle will wrestle the fish from the talons of the osprey in mid-flight!

Social and reproductive aspects
A breeding pair of ospreys typically builds a large nest out of sticks, seaweed and other debris.  They sometimes use the same nest year after year.  Within this nest, the female typically lays 2-4 white eggs with brown blotching.   

The female typically does most of the incubating.  The role of the male while the female is incubating the eggs is to provide food for the female.  He will bring food for her until the hatched chicks are 4 weeks old.    

Signs of presence
The large nests of ospreys, are sometimes found on the ground.  However, they are frequently built in power line towers, and on the tops of telephone poles.  When a nest is built upon one of these structures, it is very easy to see.

References
Special thanks to the National Audubon Society.