The federal Fish and Wildlife Service took the first step yesterday toward declaring that the emperor penguin and nine other species of penguin need the protections of the Endangered Species Act. One of the factors to be examined in the birds’ decline will be the impact of climate change on their habitat.

Acting on a petition by the Center for Biological Diversity, an environmental group based in Arizona, the service said it had enough evidence to begin a full-scale review of the 10 groups of penguins. The review is to determine things like the rates of decline and their possible causes.

One possibility is commercial fishing, which can affect the birds directly when they are caught in nets, or can provide competition for their prey, like the tiny shrimp known as krill. Other factors to be studied include habitat loss, predators and climate change, officials of the service said in a conference call yesterday.

Image An emperor penguin tending his newly hatched chick at Sea World in San Diego in 1995. Credit... Associated Press

The penguins may join a short but growing list of species, including polar bears and two corals found off Florida, whose survival is deemed at risk in part because of the increasing warmth of the atmosphere and the oceans.