Ospreys have a worldwide distribution, wintering or breeding on every continent except Antarctica. Ospreys are not known to breed in South America or Indo-Malasia, but are sometimes found there in the winter. Ospreys are winter breeders in Egypt and some Red Sea islands. Regions where ospreys are particularly abundant include Scandinavia and the Chesapeake Bay region of the United States.

There are four subspecies of ospreys, which are separated by geographic region. Pandion haliaetus carolinensis breeds in North America and the Caribbean, and winters in South America. P. h. haliaetus breeds in the Palearctic region (Europe, north Africa and in Asia, north of the Himalayas) and winters in south Africa, India and the East Indies. P. h. ridgwayi is a non-migratory subspecies. It resides in the Caribbean, with a range that extends from the Bahamas and Cuba to southeast Mexico and Belize. The final subspecies, P. h. leucocephalus is also a non-migratory subspecies. Its range includes Australia and the southwest Pacific. In Suriname mostly found from september to march. The osprey does not breed on the South American continent, but large numbers visit from the Northern Nearctic region.

Ospreys have a wide distribution because they are able to live almost anywhere where there are safe nest sites and shallow water with abundant fish. Nests are generally found within 3 to 5 km of a water body such as a salt marsh, mangrove swamp, cypress swamp, lake, bog, reservoir or river. The frequency with which each of these habitat types is used varies by geographic region.
Ospreys choose structures that can support a bulky nest, and that are safe from ground-based predators. Nest sites can be safe from predators either by being difficult for a predator to climb (e.g. on a cliff) or by being over water or on a small island. Over-water nest sites that are often used by ospreys include buoys and channel markers, dead trees and artificial nest platforms. Ospreys have also been known to nest on various man-made structures, such as power poles, duck blinds, communication towers, buildings and even billboards. In many cases, nests that are built on artificial structures such as nest platforms and power poles are more stable and fledge more chicks per breeding season than nests on naturally-occuring structures.

Non-migratory populations breed and winter in the same location, though they may wander several hours from their nest during the non-breeding season. These populations begin breeding between December and March. Migratory populations generally breed where winters are cold enough to drive fish into deep water where they are inaccessible. These populations begin breeding in April or May.
Courtship in ospreys centers on food and nest sites. In migratory osprey populations, males and females arrive at the nest site separately, the male often arriving several days earlier than the female. Male ospreys sometimes perform a conspicuous aerial display near the nest site. Both sexes collect materials for the nest, but the female does most of the arranging of materials at the nest. Osprey nests are typically constructed of sticks, and lined with softer materials such as seaweed, kelp, grasses or cardboard. Osprey pairs use the same nest year after year, but must spend some time each year repairing it and adding materials before eggs can be laid.
Once a pair has established a nest, the male begins to deliver food to the female. This feeding continues until the young fledge or the nest fails. Generally, females that receive more food are more receptive to mating attempts by the male, and are less likely to copulate with other males. Females beg for food from their mates, and occasionally from neighboring males if they are not well fed by their mate. Males may protect their paternity by feeding their mate.
Ospreys are generally monogamous. Non-migratory populations breed in the winter and spring, laying eggs between December and March. The breeding season of migratory populations occurs in the spring and summer, with egg laying in April and May. Two to four eggs are laid over a period of several days, each 1 to 2 days apart. Both the male and female incubate the eggs, which hatch after approximately 40 days. Because incubation starts when the first egg is laid, the eggs hatch asynchronously in the order in which they were laid. Chicks that hatch first are larger and have a competitive advantage over those that are hatch later. If food becomes scarce, the smaller chicks are less successful in competing for food, and often die.
When osprey chicks hatch, they are covered in white down, which is replaced by charcoal-colored down after approximately 10 days. Feathers begin to replace the down at approximately two weeks. By one month after hatching, chicks have reached 70 to 80% of the adult size. Osprey chicks fledge between 48 and 76 days old. Generally, chicks in migratory populations fledge sooner than those in non-migratory populations. After fledging, young ospreys begin to hunt on their own. However, they often continue to return to the nest to receive food from their parents for two to eight weeks after fledging. Because ospreys migrate individually, juvenile ospreys must be fully independent of their parents by the time the southward migration begins.
Ospreys are sexually mature at approximately 3 years old, but may not breed until age 5 in areas where nest sites are scarce. Migratory ospreys in both Europe and the U.S. exhibit a pattern of behavior that is unusual in raptors. Rather than returning to the breeding grounds in their first summer, yearling ospreys almost always remain on the wintering grounds throughout the year. They then return to the breeding grounds the following summer when they are more likely to be able to breed successfully. This strategy allows young ospreys that are too physically immature to breed to avoid an unnecessary migration.

Ospreys hunt for fish on the wing (less often from a perch), flapping and gliding 10 to 40 meters above the water. When an osprey spots a fish, it hovers briefly, then dives toward the surface of 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, almost horizontal wing beats to lift itself and its prey from the water. Once airborne, 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 presumably makes the fish more aerodynamic, and easier to carry. The osprey then takes the fish to a perch, often near the nest, to eat. Osprey generally eat fish beginning with the head and working toward the tail. A male who is also providing food for a mate and offspring during the breeding season will typically consume at least part of the fish before delivering the remainder to the female. Ospreys do not cache fish. If a fish is larger than an osprey (and his mate and offspring if breeding) can consume, the fish is discarded, carried around with the osprey, or left in the nest. Ospreys do not generally need to drink water. Fish flesh supplies sufficient amounts of water to meet their requirements.

This species has a large global range; the total size has not yet been quantified, but the Extent of Occurrence in Africa and the Americas combined is estimated to be 9,670,000 km². It has a large global population estimated to be 460,000 individuals (Rich et al. 2003). Global population trends have not been quantified, but the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e. declining more than 30% in ten years or three generations). For these reasons, the species is evaluated as Least Concern.

Resident in tropical and subtropical latitudes. Migratory elsewhere, generally moving to latitudes near the equator: Amazon Basin and North coast of South America; and coastal West Africa from Senegal to the equator.

article number 1 Title
COURTSHIP FEEDING AND OSPREY REPRODUCTION
Author(s): ALAN POOLE
Abstract: A female Osprey (Pandion haliaetus) usually is fed exclusively by its mate between pair formation and egg-laying. Laying dates and courtship periods, but not clutch size, egg size, breeding success or..[more]..
Source: The Auk 102: 479-492
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