Osprey (Pandion haliaetus)

Although, in appearance & prey, the osprey resembles Fish (or Sea) Eagles, it appears that the Osprey followed a different evolutionary route, & so has merited a genus (Pandion) all of its own. The scientific name comes from Pandion, the mythical king of Athens, whose two daughters, Procne & Philomel, became involved with Tereus, the son of the king of Thrace, which angered the gods. They changed Procne into a swallow, Procne into a nightingale & Tereus into a hawk condemned to chase Procne & Philomel for eternity. So the first part of the scientific name is doubly wrong, firstly it was Tereus not Pandion turned into a hawk & secondly, the Osprey eats fish not swallows or nightingales. The haliaetus comes from the Greek "halos" meaning "sea" and "aetus" meaning "eagle". Coincidentally, "haliaetus" is incorrectly spelt & should be "haliaeetus", which is used for the scientific name for the Fish Eagles. (Marie-Jules-Cesar Lelorgne de Savigny, the ornithologist who gave the Osprey its scientific name, must have had a really bad day - see also the sparrowhawk). The English name is thought to derive from the Old French "ospreit", deriving from the Latin "avis praedae" meaning "bird of prey". (Another derivation is thought to be from the Latin "ossifragus" meaning "bone-breaker", though there is no clear explanation why.)

The osprey is the only member of the genus Pandion. They appear to have diverged from the rest of the Accipitridae raptors around 24-30 million years ago.

In common with many Fish Eagles, the osprey is dark coloured above & white below, the light colouring is being less visible to it prey. It has large, scaly feet with sharp spicules (little spines) beneath the talon and, unlike other raptors, all of its toes are the same length, with the outer toe being reversible. The spicules & reversed outer toe give it better grip on its often slippery prey - they prey predominantly on fish eater, though they will eat small mammals, reptiles & invertebrates.

Osprey catch their prey with a feet first dive, sometimes from a hover, more often from a glide, unlike the Fish (Sea) Eagles they will often submerse themselves in order to catch the fish. In order to reduce the drag of water, as they fly off, the position of the fish is adjusted so that it comes out head first, again this is unlike Fish Eagles, which tend to bring the fish out sideways, held in both feet. There have been rare reports of Ospreys catching two fish in a single dive.

Ospreys are found throughout all of the inhabited continents. Though wintering in South America, they do not breed there. In the UK, they were persecuted to extinction in this country in 1916, by fishermen, gamekeepers and egg collectors. Recolonisation started in 1954, with a single pair in Scotland, thought to have come from Sweden. Because of its rarity, it is still a target for egg-collectors, despite legal protection (it is a species protected by special penalties in the UK, if kept in captivity, it must be ringed & registered) and round-the-clock surveillance of nest sites. In May 2002, two nests in Perthshire were robbed of all of their eggs, despite being protected by coils of razor wire. The UK population in 1999 was 136 pairs, all in Scotland. There currently are reintroduction & protection schemes to reinstate a healthy population in this country, including a release scheme at Rutland Water, where nesting platforms have been provided, & continual surveillance in the hope that a permanent breeding stock will be established. Since 1996, 12 fledgling a year have been released at Rutland Water, which is the largest man-made lake in Europe & a stopping-off point for many migrating birds. In June 2001, the first osprey born in England for over 150 years was hatched at Rutland Water.

Ospreys start to breed at three years old, breeding takes place between March to September. Nests are made at the tops of trees (usually coniferous, if available), on rocky pinnacles or on articial platforms. Normally around 3 eggs are laid. Incubation takes around 6 weeks. The young are fully fledged at around 7-8 weeks after hatching. In the wild, between 40 & 60% of all the young die in their first year, those that do survive can usually live for 15-20 years in the wild, some have been known tom live for over 30 years.

Ospreys appear to have developed somewhat in their fish catching ability over the last 2350 years, in 350BC the osprey was described by Aristotle in his "Natural History" as follows : "This bird has a large, thick neck, curved wings & broad tail feathers; it lives near the sea, grasps its prey with its talons, and often, from an inability to carry it, tumbles down into the water"

Mythology & Folklore :

Due to the Osprey's high success rate in huntining, in Bolivia the natives used to believe that they could become better hunters by implanting Osprey bones under their skin.

IUCN Red List Status :

Least Concern (LC)

AOU Data :

Species Number : 364.0
Alpha Code : OSPR
Common Name : Osprey
Longevity Record : 26yrs 2months

Also Called :

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