Once Critically Endangered, Osprey Numbers Soar in Connecticut

In what’s being hailed as “one of the great conservation success stories,” a record number of osprey fledglings were observed in Connecticut in 2023, according to the Connecticut Audubon Society (CAS).

Relying on volunteer “citizen-scientists” who keep tabs on raptor nests in the state year-round, CAS reports that a record 881 ospreys successfully fledged last year. This means they grew the feathers needed for flight. The milestone is a key step in the change from infancy to adulthood for the birds of prey. It also marks a rebound for ospreys along the coast of Long Island Sound. The Sound is a vital nesting site for the species.

“Connecticut was one of the few places where there was (lasting numbers) that hung on into the 1970s,” Alan Poole told The Stamford Advocate. Poole is an associate of the Cornell Lab of Ornithology.

What happened to the ospreys in the 1970s? The US-wide use of the insecticide DDT cut their numbers. Ospreys and other raptors consumed prey dosed with DDT. It then built up in their bodies. The chemical seeped into their eggs. This weakened the shells. It caused nesting mothers to crush them before chicks could hatch. By 1972, there were fewer than 10 active nests statewide.

DDT was banned in 1972. After its ban, conservationists in Connecticut staged a campaign. They aimed to build nest boxes and protect habitats. They also sought to record osprey population numbers. Those efforts seem to be paying off in big ways. Connecticut now boasts 690 active osprey nests.

Milan Bull is senior director of science and conservation for the CAS. “It shows that conservation works and these are the numbers to prove it,” Bull told the Advocate. 

GIF from GIPHY courtesy of US Fish and Wildlife Service.

Reflect: How do you think human actions, both positive and negative, can impact the populations of animals in their natural habitats?