Steller Sea Lion Populations in Alaska Declined After the 1970s

Multiple Choice

Steller sea lion populations in Alaska declined after the 1970s, and survivors were smaller and had lower birth rates.Earlier populations had fed mostly on herring, a fish rich in fat.When herring declined, they fed mostly on cod and haddock, which are larger but lower in fat.This suggests that sea lion population changes can be directly linked to

A) changes in local climate.
B) decline in a high-energy food source.
C) decline in total amount of food available.
D) changes in sea lions' ability to process food.
E) entry of another predator into the ecosystem.