The Atlantic puffin population is at risk in the United States, and there are signs the seabirds are in distress in other parts of the world. Scientists say the comical-looking seabirds have been dying of starvation and losing body weight, possibly because of shifting fish populations as ocean temperatures rise. The fledgling survival rates at Maine’s two largest puffin colonies plunged last summer, and the average weight of puffins on Canada’s Machias Seal Island off eastern Maine has been falling since 2000. Dozens of emaciated puffins were found washed ashore in Massachusetts and Bermuda this past winter, likely victims of starvation. Scientists say puffins appear to be eating more butterfish and not as much herring, puffins’ preferred food, possibly because of warming waters.