Bone Breakers

CS_LT_0031CCX_edited-1Sometimes mistaken for an Eagle, the Osprey is a large fish eating bird commonly found along the coast and near freshwater lakes and is the second most widely distributed raptor species in the world behind the Peregrine Falcon.  The Osprey is found everywhere on earth except Antarctica.  It’s not often that Ospreys are admitted to the Outer Banks Wildlife Shelter in Newport because they usually manage to stay above the fray and out of the way of humans.  However, when it does happen, it’s usually a human interference incident, which was the case when two infants were admitted to the shelter a while back.  Their nest, aboard a Virginia boat, was not discovered until the Captain docked in North Carolina. Although adult Ospreys do not handle captivity well, a youngster’s demands focus on food, development and protection which our shelter is very experienced in providing.  Ospreys are brown on top with a bright white underside, dark specks on the wings, and dark bands on the tail feathers. The head is white with a dark mask across yellow eyes, reaching to the sides of the neck. Their beak is black, with a bluish fleshy upper mandible membrane, and their feet are white with black talons. Its toes are of equal length and the talons rounded, rather than grooved, which is something they have in common with owls, including their outer reversible toes.  It is a large raptor, reaching more than two feet in length and 71 inches across the wings.  Male and female Ospreys are very similar in appearance, but the male has a slimmer body and narrower wings. CS_I7Z8422Their wings and legs have adapted over time to enjoy and exhibit great joint flexibility. An example of this limberness occurs when flying towards a bright light such as the sun. They are able to bend the joint in their wing to shield their eyes from the light to aid safety while flying.  In flight, the Osprey’s arched wings and drooping “hands,” give it a gull-like appearance. Their call is a series of dainty chirps described as cheep, cheep or yewk, yewk, but if disturbed by activity near the nest, the call becomes more of a sharp and frenzied whistle, cheereek!   Ospreys have picked up a number of nicknames over the years.  You may have heard them referred to as Sea Hawks, Fish Eagles or Fish Hawks which all come from inferences of keen eyesight, agility, timing, strong talons and expertise in catching fish.  The names have also been attributed because they choose nesting sites near bodies of water that can provide an adequate food supply.  The bird’s common name, Osprey, is derived from the Latin word ossifragus, meaning “a bone breaker.”  Fish make up 99 percent of their diet, so these feathered, aerial bone breakers certainly handle dietary fish bones better than humans do. Occasionally, the Osprey may prey on rodents, rabbits, amphibians, other birds and small reptiles.  Ospreys have vision well adapted to detecting underwater objects from the air. A meal is first sighted when the Osprey is above the water up to 130 feet. The bird hovers momentarily and then plunges feet first into the water.  On occasion, an Osprey will immerse entirely in the water, which is a rare behavior for raptors. With those reversible outer toes, sharp spicules on the underside of the toes, closable nostrils to keep out water during dives and backwards-facing scales on the talons which act as barbs to help hold its catch, they are well suited to be awesome fisher birds. While in flight, the Osprey will orient its catch headfirst to ease wind resistance. Ospreys reach sexual maturity and begin breeding around the age of three to four, usually mate for life and return to the same nesting site every year. CS_IMG_8676_CS_X The nest is a large pile of sticks, driftwood and seaweed built in forks of trees, rocky outcrops, utility poles, artificial platforms provided by preservationists or found on a small offshore island.  The female lays two to four eggs within a month and relies on the size of the nest to conserve heat, but both parents help to incubate. The eggs are whitish with splotches of reddish-brown and are incubated for about five weeks before hatching. Newly hatched chicks weigh in at 1.8 to 2.1 ounces and will fledge in 8 to 10 weeks.  Once the young are hatched, the male Osprey takes responsibility for providing food. When food is scarce, the first chicks to hatch are most likely to survive.  These large, rangy hawks have adapted well around humans and have rebounded in numbers following the 1970’s ban on the pesticide DDT, although still considered a threatened species.The typical lifespan is 7 to 10 years, though individuals can age 20 to 25 years. The oldest recorded wild Osprey lived in Europe and is estimated as reaching the age of thirty. In North America, Bald Eagles are the only major predators of Osprey eggs and juveniles.   However, the more common predation by an Eagle is stealing the Osprey’s catch rather than a family member. Eagles often force Ospreys to drop fish they have caught and steal them in midair.  Watching Osprey tending to their nest and offspring is a wonderful way to spend a morning or afternoon; another way to safely enjoy our coastal wildlife!  Bring your binoculars!

Happy Summer Everyone! 

Linda Bergman-Althouse,

author of  “Save Them All”