These majestic creatures are birds of many names; they are known as fish hawks, river hawks, and seahawks. They love to spend their time by the waterโฆ freshwater, saltwater, and everything in between. Ospreys are most frequent along coastal estuaries and salt marshes, but can also be found among rivers, lakes, and reservoirs. Once grouped with other hawks for classification, these too-cool-for-school raptors were eventually bestowed with their very own scientific family name (Pandionidae) because of their unique characteristics. Theyโre not like other birds. Ospreys have gorgeous barred flight feathers, a beautiful hooked beak, and a white head with a thick brown stripe on each side over the eye.
Breeding
Most ospreys migrate yearly, breeding in the north and wintering in the south. They build nests from sticks and other smaller materials in large piles on dead trees and other surfaces that are close to water and open to the sky. Ospreys usually lay three eggs for the year and males and females share parental duties incubating them. The chicks hatch at different times so the older ones have a size and strength advantage over their younger siblings. If the family falls on hard times and food is in short supply the bigger birds will often take it all for themselves, leaving the younger ones to perish.
Hunting
Ospreys are gifted fishers that hunt by soaring over the water, scanning for fish near the surface, then plunging down 30 to 100 ft talon first to snatch their prey up. They even take care to orient the fish with their head forward for more aerodynamic flight while carrying them. Now thatโs what I call efficiency! Eagles are the natural rival of ospreys and are known to hassle ospreys to force them to drop their fish and rob them of their hard-earned catch.
Threats and Conservation Efforts
With widespread application of DDT and other pesticides in the 50s, osprey populations in North America declined and became endangered. DDT interferes with the birdโs calcium metabolism which led to them laying eggs with thin shells, too fragile to survive or infertile from the beginning. After several osprey-harming pesticides were banned in 1972, osprey populations rebounded significantly.
Ospreys are also dealing with habitat loss due to human development. At the same time, human development can create places for ospreys to nest on such as on poles, channel markers, duck blinds, and other structures. Ever noticed those tall man-made platforms in and around the water? Chances are that was an osprey-nesting platform. Many property owners near large bodies of water have constructed these to encourage ospreys to nest and help strengthen the local population.
Uncertain future
Global climate change contributes to increasingly severe spring heat waves that endanger young ospreys still in the nest. Changing temperatures are already having observable impacts on many birdsโ migration timing and geographical range. According to the Audubon Society, ospreys may lose 79 percent of their summer range by 2080.
The only hope to protect these magnificent raptors against this growing threat is for humans to take action to reduce greenhouse gas emissions substantially and slow down the rate of global average surface temperature rise.
About the Author
Christy Ferguson is a summer intern with the Maryland Coastal Bays Program and recent graduate from the University of Maryland Baltimore County with a BS in environmental science and geography. This summer she will be assisting with water quality monitoring, restoration monitoring, wetland assessments, seining at Castaways, and Ocean City Estuary Explorers camp. Christy loves getting to see new wildlife species out in the wild and learning to identify them.
