Though traces of chemicals like the pesticide DDT are still being passed on to new generations of ospreys, the birds of prey are faring well in the Chesapeake Bay, researchers have found.
A three-year study led by the U.S. Geological Survey found residues of long-banned toxins in osprey eggs. Researchers also found ospreys are facing ongoing exposure to chemicals used as flame retardants and in pharmaceutical products.
The ospreys are nevertheless faring well, according to the study published April 1 in the journal Environmental Toxicology and Chemistry.
"Osprey populations are thriving almost everywhere in the Chesapeake," Rebecca Lazarus, a researcher at the USGS Patuxent Wildlife Research Center and the lead author, said in a statement. "We found them nesting in some of the most highly contaminated areas in the Bay and we did not find any relationship between contaminants and their nests' productivity."
Ospreys live all around the world but a concentration of them is found in the Chesapeake, the summer home of about one in four ospreys in the United States. There are about 10,000 nesting pairs of ospreys in the bay, the study found.
In some locations around the bay, researchers found high levels of toxic compounds known as PCBs in osprey eggs. That is despite the fact that the chemicals were banned in the 1970s. They also found traces of DDT, also long banned, but at levels that have declined since the 1990s, when the pesticide was blamed for declines in osprey and bald eagle populations.
The researchers raised one potential cause for concern, though -- signs of genetic damage in the blood of osprey chicks nesting near the Back River Wastewater Treatment Plant in southeastern Baltimore County.
Those interested in following ospreys up close can keep tabs on them via two different webcams. A pair of ospreys recently moved into an Annapolis nest the Chesapeake Bay Foundation started broadcasting on its website, and a Chesapeake Conservancy webcam is in its second year following a nest on Kent Island.