SeaHawk, River Hawk, Fish Hawk
52cm to 60cm
145cm to 170cm
1200g to 2000g
Adult western ospreys are similar in colour and patternation although females are normally up to twenty per cent larger than their male counterparts. In general ospreys are brown above and white below. The head has a white crown with a grey brown and white forehead and white cheeks. There is a black stripe through the yellow coloured eye extending almost to the nape of the neck. Throat and upper breast are predominantly white with a brown mottling and the remainder of the underparts and flanks are white. Underwing areas are white with a black patch across the primary coverts and a dark brown band running along the mid-wing section. In flight their wings appear narrow and they have four distinct long feathers and one slightly shorter on each wing tip. The legs are long and white with large black claws. Juveniles are similar but more of a buff colour particularly on the underparts.
Osprey in flight
A loud, often repeated yelping sound similar to ‘pyew- pyew- pyew’ signifies the presence of a nearby osprey particularly in the vicinity of its nest.
Osprey looking for fish
Ospreys survive almost entirely on a diet of fresh fish which they catch in shallow water after diving down feet first and outstretched towards the water before grabbing their prey in extremely long and sharp talons. Usually they will return to their nest or perch before consuming their meal.
Osprey catching fish
The osprey is the only bird of prey, apart from owls, that can reverse its outer toe. That is to say it can move the outer toe from a normal forward facing position to one facing backwards, giving two front facing toes and two reward facing toes all of the same length. This enables the osprey to securely holds its slippery, wet and possibly struggling prey in a vice like grip until ready for consumption.
Between March to October the western osprey is found throughout Europe except Iceland. Normally only seen close to water they migrate south to Africa for over-wintering. Ospreys prefer shallow lakes, reservoirs and rivers or coastal waters.
From a distance the western osprey could be mistaken for a juvenile gull. However, when viewed hovering above a large expanse of water or soaring over its nest area it is unmistakable with its kinked wings with well pronounced fingered wingtips, long legs and claws. Its often steep dive to pick up its prey as it strikes the water feet first is a remarkable sight. Many countries have reintroduction programmes and the western osprey population continues to grow. Conservation societies and nature reserves often have publicly accessible live webcam sites of nesting pairs.
One brood of two to four creamy white eggs with red brown spots is produced annually within a few days of the completion of the nest. Within western Europe this occurs between April and July. Nests are often used year on year and are constructed of mainly large sticks low down in trees or on artificial platforms and occasionally at ground level. Both parents take turns in incubation although during the hours of darkness the female usually performs this task. Eggs hatch approximately forty days after laying and fledging occurs between fifty to sixty days thereafter.
Osprey landing in nest
Osprey adult and chicks
The life expectancy of the western osprey is thirty years.