OSPREY Fact Sheet
Migration:
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Young Ospreys make their first migration alone, instinctively knowing where to go without
following their parents. Some Florida Ospreys are non-migratory, staying in that territory
throughout the year.
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Ospreys often fly more than 5,000 miles round trip between their summer and winter
homes.
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Satellite transmitters reveal remarkable information about Osprey migration. One study at
Martha’s Vineyard has shown that adults and juveniles take different routes to South
America. Adults take the safest routes, minimizing over-water trips, while juveniles will
cross 1,300 miles of open Atlantic in one non-stop flight, and miss the shortcut which
most adults take from Hispaniola to South America.

Ospreys often return to the same lake, river or coastal winter home each year.
Fishing

Ospreys are great anglers- successful in one out of four dives for fish.
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Ospreys are the only raptor whose front talon can pivot backward.
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Bald eagles and Great Black-backed Gulls chase Ospreys, forcing them to drop their prey;
eagles sometimes catch the stolen prey in mid-air.
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Ospreys are known as fish hawks because 99.9% of their diet is live fish. They also eat
small mammals, snakes, turtles, frogs, sandpipers, and ducks, perhaps when fish are
scarce.

After snagging fish with their talons, Ospreys shake excess water in mid-air and minimize
drag by arranging the fish head first.

The largest Osprey catch on record is 4 pounds, but most fish are 1-2 lb.
Family Life

Male Ospreys perform an aerial "sky-dance" clasping a fish or nesting material in
his talons, hovering with slow, shallow swoops as high as 600 feet or more above the nest
site, sustaining this display for 10 minutes.

Female Ospreys are larger than males and usually have a heavily striped chest; males
usually have a nearly clear white chest.

Most Ospreys are faithful to the same mate and return to the same nest.
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Ospreys grow as large as their parents before they take their first flight.
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Great Horned Owls have been known to swoop onto nearly full grown Osprey and carry
them out of the nest.
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A brood of three Osprey chicks requires up to six pounds of fish each day.

Osprey incubation is 32-42 days, with an average of 38 days. Female Ospreys do most of
the sitting, depending on males to provide food. However, some males handle up to 30% of
incubation time.

Osprey typically return to the vicinity of their hatching place when they are about two years
old; breeding for the first time when three years old.

Osprey eggs do not hatch all at once. Rather, the first chick emerges up to five days before
the last one. This arrangement favors the first hatched chicks which permits them to thrive in
years of poor food supplies. In these years, the later hatched chicks perish.

Osprey populations declined by 90% between 1950 and 1970 when nesting pairs declined
from over 1,000 pairs to about 100 pairs. The insecticide DDT caused egg shell thinning in
Osprey, Peregrine Falcon, Brown Pelican and other fish eating birds. Banning DDT in 1972
has contributed to the rebound of Osprey populations.
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The oldest known Osprey was 32 years old.