|[Note Guidelines] Photographer's Note|
|The Osprey (Pandion haliaetus), sometimes known as the sea hawk, is a diurnal, fish-eating bird of prey. It is a large raptor, reaching 60 centimetres (24 in) in length with a 2m wingspan . It is brown on the upperparts and predominantly greyish on the head and underparts, with a black eye patch and wings.|
The Osprey tolerates a wide variety of habitats, nesting in any location near a body of water providing an adequate food supply. It is found on all continents except Antarctica although in South America it occurs only as a non-breeding migrant.
As its other common name suggests, the Osprey's diet consists almost exclusively of fish. It has evolved specialised physical characteristics and exhibits unique behaviour to assist in hunting and catching prey. As a result of these unique characteristics, it has been given its own taxonomic genus, Pandion and family, Pandionidae. Four subspecies are usually recognised. Despite its propensity to nest near water, the Osprey is not a sea-eagle.
The Osprey was one of the many species described by Carolus Linnaeus in his 18th century work, Systema Naturae, and named as Falco haliaeetus. The genus Pandion was described by the French zoologist Marie Jules César Savigny in 1809.
The Osprey differs in several respects from other diurnal birds of prey. Its toes are of equal length, its tarsi are reticulate, and its talons are rounded, rather than grooved. The Osprey and Owls are the only raptors whose outer toe is reversible, allowing them to grasp their prey with two toes in front and two behind. This is particularly helpful when they grab slippery fish.  It has always presented something of a riddle to taxonomists, but here it is treated as the sole member of the family Pandionidae, and the family listed in its traditional place as part of the order Falconiformes. Other schemes place it alongside the hawks and eagles in the family Accipitridae—which itself can be regarded as making up the bulk of the order Accipitriformes or else be lumped with the Falconidae into Falconiformes. The Sibley-Ahlquist taxonomy has placed it together with the other diurnal raptors in a greatly enlarged Ciconiiformes, but this results in an unnatural paraphyletic classification
The Osprey is 0.9–2.1 kilograms (2.0–4.6 lb) in weight and 50–66 centimetres (20–26 in) long with a 127–180 centimetres (4.2–6 ft) wingspan. The upperparts are a deep, glossy brown, while the breast is white and sometimes streaked with brown, and the underparts are pure white. The head is white with a dark mask across the eyes, reaching to the sides of the neck. The irises of the eyes are golden to brown, and the transparent nictitating membrane is pale blue. The bill is black, with a blue cere, and the feet are white with black talons. A short tail and long, narrow wings with four long, finger-like feathers, and a shorter fifth, give it a very distinctive appearance.
The sexes appear fairly similar, but the adult male can be distinguished from the female by its slimmer body and narrower wings. The breast band of the male is also weaker than that of the female, or is non-existent, and the underwing coverts of the male are more uniformly pale. It is straightforward to determine the sex in a breeding pair, but harder with individual birds.
The juvenile Osprey may be identified by buff fringes to the plumage of the upperparts, a buff tone to the underparts, and streaked feathers on the head. During spring, barring on the underwings and flight feathers is a better indicator of a young bird, due to wear on the upperparts.
In flight, the Osprey has arched wings and drooping "hands", giving it a gull-like appearance. The call is a series of sharp whistles, described as cheep, cheep or yewk, yewk. If disturbed by activity near the nest, the call is a frenzied cheereek
jeanpaul, lovenature has marked this note useful
Only registered TrekNature members may rate photo notes.