The warming of Alaska's waters is causing a decline in seabird populations and emptying colonies, according to ecologists. The warmer waters are leading to a reduction in the quality and quantity of phytoplankton, which is the basis of the food chain for fish, birds and marine mammals. The lower-calorie phytoplankton is being eaten by zooplankton and small fish, leading to less and lower-quality food for larger fish, marine mammals and birds. The seabirds are also struggling to find food as fish and plankton migrate to deeper, cooler waters. The decline in seabirds is a concern for native communities who rely on them for food.