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Pandion haliaetus

What do they look like?





  • Sexual Dimorphism
  • female larger
  • sexes colored or patterned differently
  • Range mass
    1200 to 2000 g
    42.29 to 70.48 oz
  • Range length
    55 to 58 cm
    21.65 to 22.83 in
  • Range wingspan
    145 to 170 cm
    57.09 to 66.93 in

Where do they live?


What kind of habitat do they need?



How do they reproduce?








  • How often does reproduction occur?
    Ospreys breed once yearly.
  • Breeding season
  • Range eggs per season
    1 to 7
  • Average eggs per season
  • Average eggs per season
  • Range time to hatching
    32 to 43 days
  • Range fledging age
    48 to 59 days
  • Range time to independence
    7 to 17 weeks
  • Average age at sexual or reproductive maturity (female)
    3 years
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    1095 days
  • Average age at sexual or reproductive maturity (male)
    3 years
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    1095 days

Male and female ospreys both care for their young. They feed the chicks and protect them from predators and cool, wet weather. The male provides all of the fish for the chicks before they can fly. This means that males have to catch up 10 fish each day for the female and the chicks. The parents tear the fish into small pieces for the chicks to eat. Osprey parents hunt fish for their chicks until the chicks can hunt enough fish to feed themselves. Chicks can usually feed themselves two to eight weeks after they begin flying. (Poole, 1989; Poole, 1994)

During the first few weeks after hatching, osprey chicks cannot control their body temperature very well. The female parent broods the chicks frequently for the first two weeks and during very hot or cool weather until they are about four weeks old. Both parents spend a lot of time protecting the nest from other ospreys and potential predators. (Poole, 1989; Poole, 1994; Poole, et al., 2002)

  • Parental Investment
  • no parental involvement
  • altricial
  • pre-hatching/birth
    • provisioning
      • male
    • protecting
      • male
      • female
  • pre-weaning/fledging
    • provisioning
      • male
      • female
    • protecting
      • male
      • female
  • pre-independence
    • provisioning
      • male
      • female
    • protecting
      • male
      • female

How long do they live?


How do they behave?

Ospreys can be migratory or sedentary (non-migratory). Non-migratory populations breed and winter in the same location. Migratory osprey populations generally breed north of the non-migratory populations and winter south of them. (Fernandez and Fernandez, 1977; Poole, 1989; Poole, 1994)

Ospreys can build their nests close together in colonies or far from other pairs. Most raptors don’t live in colonies because they defend a hunting territory around their nest. Ospreys have to hunt over such a large area to find enough fish that they can’t defend a hunting territory. Sometimes, they even hunt together because they can catch more fish that way. Instead of defending a territory, ospreys just defend their nest from other ospreys and from predators. (Poole, 1989; Poole, 1994; Poole, et al., 2002)

Home Range


How do they communicate with each other?

Ospreys use up to five different calls to communicate with each other. They also use visual displays, like special flight displays or specific body positions to communicate. Often calls and visual displays are used together. Calls are used to for begging, alarm, courtship, and nest defense. Alarm calls are often given when a potential predator or disturbance such as a boat or human approaches the nest. Ospreys giving alarm calls usually stand very erect on the nest, or dive at the disturbance. (Poole, 1989; Poole, 1994; Poole, et al., 2002)

What do they eat?

Ospreys are unusual among raptors for being piscivores. Their diet consists almost entirely of fish (≥99% of prey items). They are opportunistic, and will eat whatever fish species they can catch – either in shallow waters, or near the surface of deeper waters. North American ospreys are known to eat more than 80 different species of fish. (Poole, 1989; Poole, et al., 2002)

Ospreys hunt for fish while flapping and gliding 10 to 40 meters above the water. When an osprey spots a fish, it hovers briefly, then dives toward the water. Just before hitting the water, the osprey swings its legs forward and bends its wings back, plunging feet-first into the water. The osprey uses strong wing beats to lift itself and the fish out of the water. Once airborne again, the osprey rearranges the fish in its feet, carrying it with one foot in front of the other so that the fish is facing forward. This position probably makes the fish easier to fly with. The osprey then takes the fish to a perch to eat. (Poole, 1989; Poole, 1994; Poole, et al., 2002)

Ospreys generally eat fish starting at the head and working toward the tail. A male who is also hunting food for a mate and chicks during the breeding season will usually eat at least part of the fish before delivering the rest to the female. Ospreys do not usually need to drink water. They get enough water from the fish that they eat. (Poole, 1989; Poole, 1994; Poole, et al., 2002)

Ospreys successfully catch fish on 24 to 74% of their dives. Ospreys are usually more successful at mid-tide and when the weather is calm. (Poole, et al., 2002)

Though ospreys eat mostly fish, they have occasionally been seen eating other things, including birds, snakes, voles, squirrels, muskrats (Ondatra zibethicus), salamanders, conchs, and even a small alligator (Alligator mississippiensis). Reports of ospreys feeding on carrion are rare. However, they have been observed eating dead white-tailed deer (Odocoileus virginianus) and opossum (Didelphis virginiana). (Poole, et al., 2002)

  • Animal Foods
  • birds
  • mammals
  • amphibians
  • reptiles
  • fish
  • carrion
  • mollusks

What eats them and how do they avoid being eaten?


Raccoons, snakes and other climbing animals are probably predators of osprey eggs and nestlings. This is probably why ospreys in many areas build their nests over water. Crocodiles may also prey on wintering ospreys. Nile crocodiles sometimes kill ospreys bathing and roosting near water in Africa. (Poole, 1989; Poole, et al., 2002)

  • These animal colors help protect them
  • cryptic

What roles do they have in the ecosystem?

While ospreys provide food for some species, they are probably not the main food source for any species. Because ospreys prey on fish, they probably have a small effect on local fish populations. Like most predators, ospreys are host to many different species of parasites, including feather mites. (Poole, et al., 2002)

Ospreys nests are used by many other species of birds. Smaller cavity-nesting species, such as common grackles, tree swallows, barn swallows, European starlings and house sparrows build nests inside osprey nests. Other larger species take over osprey nests for their own use in the spring before the resident ospreys return. In North America, these species include great blue herons, Canada geese, bald eagles, Red-tailed hawks, Great horned owls, herring gulls and common ravens. (Poole, et al., 2002)

Ospreys in some areas, especially northern forested regions, may have historically depended on beavers to create habitat for them. Beavers create osprey habitat by building dams, which create shallow ponds for fishing and dead trees for building nests. (Poole, et al., 2002)

Do they cause problems?

There are no known negative impacts of ospreys on humans. In the past, some fishermen have believed that ospreys competed with them for fish. However, studies have shown that ospreys take a much smaller amount of fish than the fishermen, and do not compete with fishermen for fish. (Poole, 1989)

How do they interact with us?

Ospreys help attract ecotourism to areas. They may also be a valuable indicator species for monitoring the health of large rivers, bays and estuaries. If water is polluted, the pollutants will be found in the fish that the ospreys eat. Since ospreys are sensitive to many of these pollutants, the health of the ospreys can tell us about the health of the aquatic ecosystem where they live. (Poole, 1989; Poole, et al., 2002)

  • Ways that people benefit from these animals:
  • ecotourism

Are they endangered?


In the late 19th and early 20th centuries, the main threats to osprey populations were egg collectors and shootings. Shooting an egg-collection became less common by about 1950, though ospreys are still shot occasionally. Osprey populations in many areas were accidentally poisoned by the pesticide DDT (dichloro-diphenyl-trichloroethane), and many populations shrunk from the 1950’s through the 1970’s. DDT was banned in the U.S. around 1970, but is still used in some countries where ospreys spend the winter. Populations of ospreys grew again after DDT was banned. Ospreys are now almost as abundant as they have ever been. Ospreys have been helped by people constructing artificial nest structures for them, hacking projects and new habitat that has been created by man-made reservoirs. (LaPierre, 1991; Poole, 1989; Poole, et al., 2002)

Some more information...



















University of Michigan Museum of ZoologyNational Science Foundation

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Watkins, P. 2000. "Pandion haliaetus" (On-line), Animal Diversity Web. Accessed September 27, 2021 at


University of Michigan