New Jersey is officially claiming victory in the fight to save two iconic birds.

Bald eagles and ospreys were both removed from the state endangered species list on Monday, capping off a dramatic recovery in recent decades. In the early 1970s, just 50 ospreys were known to remain in the Garden State, and by the early 1980s, there was just a single known bald eagle pair left in New Jersey, in a remote area near Delaware Bay.

Both bird species were pushed to the brink in the 1970s by the widespread use of DDT (dichloro-diphenyl-trichloroethane), a chemical pesticide that accumulated in the food chain and caused the birds to lay eggs with shells that were too thin to survive.

The use of DDT was banned federally in 1972, and state efforts to restore the local bald eagle population kicked off in the ’80s with the relocation of eagles from Canada and an artificial incubation program. The recovery story is part of a national trend, as bald eagles were taken off the federal endangered and threatened lists in 2007.

Work to save the ospreys focused on moving threatened nests to areas where DDT was less frequently used and building hundreds of stands in marshes and coastal areas to give ospreys places to build new nests.