The osprey is unique amongst birds of prey in the way it is adapted to live on fish, spotting them with their acute, binocular vision and swooping to catch them with long, curved claws.
The osprey only weighs around 1.5kg – or the weight of a small chicken – but has a wingspan of 145–170cm. Of the Scottish birds of prey, only the golden eagle and sea eagle have larger wingspans.
A powerful creature, the osprey can raise itself and a fish weighing as much as 2kg out of the water and can also lift large branches to its tree-top nest.
In Scotland, the osprey's diet consists almost solely of trout and pike. Unique amongst birds of prey, the osprey is adapted for living exclusively on fish.
Accurate vision allows it to spot fish swimming near the surface from up to 70 metres above the water.
A 2008 study by Roy Dennis found over 200 breeding pairs of osprey in Scotland.
Those birds that breed in Scotland spend the winter in warmer African climes. Ospreys are resident in Scotland from March/April until September.
Migration across thousands of miles is aided by a special magnetic organ in the osprey's brain which is aligned to the natural polarity of the earth.
Landmarks on the ground and hereditary routes also play a part in navigation.
Scottish ringed birds are generally found to winter in Gambia and Senegal in West Africa.
More than half the young birds die of starvation during their first year. They spend their first two years in Africa before migrating north to their summer breeding area.
