EAST MACHIAS, Maine (AP) — Atlantic salmon laid a record number of eggs in a Maine river last year, according to a conservation group that tracks the animal's status in the wild.

The fish are considered endangered in the U.S. by the federal government, and they only appear in a handful of Maine rivers. The Downeast Salmon Federation said the high number of eggs shows that efforts to bring them back in Maine's river systems is working.

Biologists counted 61 of the nests the fish build for spawning in the East Machias River. The Downeast Salmon Federation's executive director, Dwayne Shaw, said that's six times the number counted in the river since the federation started tracking the fish's egg nesting patterns two decades ago.

The federation counted only 10 of the nests in 2018, the Bangor Daily News reported. That was about an average number. The nests carry about 4,000 eggs each.

State regulators also reported that a higher number of salmon returned to the Penobscot River last year.