Question

Marine biologist Dr. James Estes researched sea otters and their habitats in the Aleutian Islands of the North Pacific Ocean. Sea otters feed on animals such as crabs and urchins. Islands with sea otters contained a lot of kelp, a seaweed that is an important food source for fish and other sea animals. However, Islands without otters had large populations of urchins but no kelp since sea urchins feed on this seaweed. Since sea otters are able to control the population of urchins, this allows for kelp to freely grow in those areas. Given this information, what term best describes the otter in the Aleutian Islands ecosystem?

a.keystone species

b.producer

c.apex predator

d.decomposer

Answer 1

a. keystone species