by Sharon Hanzik, PWL Member
If you are an avid birder, you most likely know what the title is referring to. If you haven’t a clue, I can sum it up in one word, osprey. The osprey has several nicknames, including seahawk, fishhawk, and riverhawk. However it is not classified as a hawk. In fact, it has been given its own taxonomic genus, Pandion. I love it when a scientific name is easy to explain. In the case of the osprey, it is quite simple: Pandion (king) haliaetus (halos-sea, aetas – eagle). The osprey is one of my favorite birds. From their high-pitched call to watching them catch a fish, I get excited and can’t look away until the bird is out of sight. I’m as much in awe as if watching a bald eagle do the same. Bald eagles have a bit more of a varied diet beyond fish. Fish make up the majority of the osprey diet, so one will definitely find them near water. In fact, 99% of the bird’s diet is fish, with the occasional addition of rodents, rabbits, reptiles, amphibians and crustaceans filling that remaining 1%.
Osprey are primarily solitary and roost alone or in small flocks. It is fairly easy to identify the bird in flight. When seen from below, there is a noticeable “kink” in its long, slender wings creating an “M” shape. They hover briefly over water before diving. Females are slightly larger than males. Upon close inspection, females may exhibit a slightly larger “necklace” of brown feathers across their chest. When one is mainly a piscivorous raptor, one is bestowed with certain specialty adaptations. As with owls, it has reversible outer toes. This adaptation creates an “X” shape providing for a larger surface area of the foot, making it easier to snag a fish under water when visibility is low. (Think of how you would hold your bare hand to catch an object. You would not hold your fingers and thumbs close together. You would spread your fingers and thumbs as far apart as possible, creating a larger surface area.) They have long legs. Backward facing scales on their talons and tiny needle-like structures called spicules on the bottoms of their toes act as barbs to help hold their catch. As the birds are known to submerge at depths of 3 feet, they are every bit the snorkeler, equipped with closable nostrils and dense, oily, waterproof plumage. Nictitating membranes help protect their eyes. After catching a fish, they turn it head first to decrease drag in flight.
Naturally, they breed and nest near freshwater lakes, rivers and coastal brackish waters. They breed at around 3-4 years of age but may delay to ages 5-7 if population densities are high. Tree removal and shoreline development have decreased the number of suitable nesting sites, leading to delayed breeding. To counteract their negative impact, humans have stepped in, creating nesting platforms to aid in this “housing shortage”. The birds usually mate for life. The male selects the site. Both collect materials and construct the nest. However, the female is the foreman who directs the placement of materials. They usually use the same nest year after year. Typically, they lay 1-4 eggs during the spring and summer months, depending on latitude. Both adults participate in incubation which lasts approximately 30-40 days. The young will fledge after 2 months and remain another 2 in training. They can live up to 25 years.
Osprey can be found on every continent excluding Antarctica. In North America, they are resident to long-distance migrants to Central and South America. Some populations overwinter in the US from FL to the southern Gulf of Mexico. Along with the Bald Eagle, it has made an impressive recovery from the impact of DDT. However, in some states they are still listed as extirpated, threatened or endangered, especially inland where pesticides continue to decimate their populations. If you would like to track, monitor, and record their nesting populations, visit www.ospreywatch.org.
Osprey Identification, All About Birds, Cornell Lab of Ornithology