VIMS

How to identify an osprey

The osprey is one of the largest birds of prey in North America. On average, females weigh about 15–20% more than males, and are 5–10% longer in wing, tail, claw, and bill length.

How to identify an osprey. Female ospreys have a necklace of brown feathers across their chest. The chest of the male is completely white. Photo by Jon Lucy.Length

52-60cm (20.5-23.6 inches)

Wingspan

150-180 centimeters (5-6 feet)

Weight
1,400 to 2,000 grams (3 - 4.4 pounds)
Coloration

Generally white below and brown above. White belly and throat; breast is mostly white with some brown mottling. Back and upper surface of wings are dark chocolate-brown. Crown and forehead are also white with brown streak that runs from the beak, around the eye, and to the nape. Iris of adult is yellow. Beak is  black and sharply curved. Upper tail is dark brown with paler bands; under tail is barred with gray. "Necklace" of brown spots across breast is more pronounced in females, which also tend to have darker heads than males. Juveniles are similar to adults, but with orange eyes and whitish mottling on back feathers.

Bearing

Wings are long and narrow, with distinctive bend at "wrists" so that wingtips angle slightly backwards. Four "finger" feathers at the end of each wing are distinctive.

Notes

The osprey is well adapted to its diet, with reversible outer toes to hold captured fish securely during flight, closable nostrils to exclude water during dives, and spiny pads on the talons to help catch fish.

Call

A series of sharp "kee, kee, kee."  Near the nest, a frenzied cheereek!

Similar To

Not easily confused with other birds of prey, except perhaps the adult Bald Eagle (Haliaeetus leucocephalus), which is larger, with all white head and tail. In flight, possibly confused at a distance with large gulls, especially adult Great Black-backed Gull (Larus marinus), but latter has all white head and tail, longer bill, white trailing edge to wing, and no crook to wings.