Scientists have been closely watching puffin populations in the Gulf of Maine in recent years, in an effort to restore the species on certain islands. This summer, puffins and other seabird populations appear to have rebounded, but are still facing a threat from predation.

Dr. Steven Kress, a scientist with the Audubon Society, has led a four-decade effort to re-establish puffin populations on island habitat off Maine’s coast. Earlier this decade the colonies shrank in the wake of storms and changes in food supply that appeared to be responding to the gulf’s rapidly warming waters.

But this year, Kress said, comparatively cooler waters in early summer were accompanied by an abundance of prey fish such as herring, hake and redfish.

“They need to find food near their nesting islands. They need to find fish that are just the right shape and size to feed their chicks. We know that it takes over 2,000 little fish to raise one chick,” he said.

At the largest colony on Eastern Egg Rock, off Bremen, 172 pairs of puffins established nests — a record by almost two dozen. And on other islands, where topography makes it easier to observe the chicks’ growth, nine out of 10 young birds made it to the fledgling stage, tripling rates seen in 2012 and 2013.

And they were big and healthy, Kress said, which should help stabilize the population going forward.

“Because they were well fed. Also we know that heavier puffin chicks at fledging survive and return in future years more than the thin-bodied chicks in poor food years,” he said.

Kress said a breeding colony of great cormorants on Seal Island, one of the last in the United States, also saw a robust number of chicks fledged. He added, however, that on islands that lacked human volunteers to wave off predators, predation by gulls and Maine’s growing eagle population appears to have driven great cormorants to abandon their colonies.

This article appears through a media partnership with Maine Public.