At Canada's largest Atlantic puffin colony, chicks are dying of starvation

The volunteers who rescue Atlantic puffin chicks — called "pufflings" — knew something was wrong when so few strays from the Witless Bay Ecological Reserve on Newfoundland's Avalon Peninsula showed up this summer.

The fledglings emerge from their burrow at night to avoid predators, but some are attracted to the lights in the rapidly growing communities on shore. Members of a group called the Puffin Patrol capture the stranded pufflings and release them into the ocean.

"The Puffin Patrol wasn't finding very many birds," said Sabina Wilhelm, a wildlife biologist with Environment and Climate Change Canada.

"And the birds that were being found were actually very small in body weight."

Some were less than half the normal size for puffins their age.

After searching a sampling of nests on the ecological reserve where Atlantic puffins congregate to breed each spring, Wilhelm and her colleagues discovered that many chicks had perished. 

The grim discovery connects the fate of the Atlantic puffin — which is not only the official bird of Newfoundland and Labrador, but a ubiquitous image in the province — with serious problems in ocean ecology, including warming ocean temperatures and a struggling, complex food web.

Tests ruled out avian flu, which caused a massive die-off of birds in 2022.

"Just based on the the body mass and just picking up the dead chicks, that were just skin and bones, so essentially they died of starvation."

Adult puffins dive for food such as capelin, a forage fish that can make up as much as 50 per cent of their diet, and bring it back to the nest, a burrow in the cliffs.

But when food is scarce the adults feed themselves, and the chick is left to starve.

Another anomaly is that puffins bred later this year, said Wilhelm.

"Normally they start fledging in early August and by the end of August, early September, most of them are gone," she said.

"There seems to have been this mismatch between breeding activity and the fact that capelin kind of disappeared.… Other years there might have still been a lot of capelin in August. That just didn't happen this year."