WASHINGTON — While osprey populations are flourishing in the nation’s capital, a troubling decline in the Chesapeake Bay region is raising concerns among wildlife researchers about broader environmental changes affecting one of North America’s most iconic raptors.
The D.C. Department of Energy and Environment reports that the District’s dozens of osprey nests produced more than 30 chicks this year. Among the 26 nests monitored, 19 successfully produced newborns — a 73% success rate that signals healthy river ecosystems in the Washington area.
The picture looks drastically different 100 miles south along the Chesapeake Bay, home to roughly 20% of the world’s osprey population. In the lower Chesapeake, reproductive success has collapsed to just 10%, with only 17 successful nests among 167 monitored sites.
The dramatic difference marks a reversal from decades of osprey recovery. After near-extinction from DDT poisoning in the mid-20th century, osprey populations surged through the 1970s, 80s and 90s, reaching approximately 10,000 breeding pairs in the Chesapeake region before beginning their recent decline.
Ospreys frequently build their nests on man-made structures such as navigational aids, channel markers, and other marine infrastructure. Many of these structures have been removed from local Chesapeake Bay areas, including the lower Eastern Shore, potentially eliminating critical nesting sites that osprey populations had come to depend on.
Researchers are investigating what environmental changes might be driving ospreys away from traditional nesting areas or into less suitable habitats. The stark contrast between thriving D.C. populations and struggling Chesapeake birds may suggest localized factors rather than species-wide decline.
The resurgence of bald eagles, another conservation success story, may also be contributing to osprey decline. Bald eagles have been known to prey on osprey nests and compete for prime nesting locations, creating additional pressure on osprey populations as eagle numbers continue to recover.
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Interesting that no mention is made in this article about what many believe is the leading cause for the decline in osprey in the lower Bay – the decimation of the menhaden population by commercial fishing. Menhaden are a critical source of nutrition for the osprey and their young. It may not be the only cause, but it is certainly a contributing factor and should have at least been mentioned.
Editor’s Note: If you actually follow the Mirror’s reporting, the Menhaden issue has been covered, but, there is no accurate data on Menhaden in the lower Bay–the data that we have indicates (according to the ASMFC) that overfishing is not occurring. Also, osprey eat all kinds of fish, not just menhaden, so we wanted to look at other indicators as to why they are moving to other areas.