May Already Affect Animals British birds nest earlier, American reptiles and amphibians move north, Pacific seabirds die off, and penguin populations wane.
Some scientists think so.
According to Humphrey Crick of the British Trust for Ornithology in Thetford, UK, many birds in Great Britain now nest earlier than they did 25 years ago. Crick et al. say the tendency toward earlier egg laying could have considerable consequences for their ecology and conservation. Earlier nesting could help if it gives juveniles more time to develop before winter. But birds might suffer if nesting gets out of step with food supplies. In the United States, some species of reptiles and amphibians appear to be expanding their range northward, according to Russell Burke of Hofstra University.