Question

this diagram shows a food chain from the river frome, a freshwater ecosystem in england.
in this food chain, the great cormorant is a tertiary consumer. why?
it eats a producer.
it eats a secondary consumer.
it eats a primary consumer.

Explanation:

In a food chain, producers (like diatoms) make their own food. Primary consumers (midge larvae) eat producers. Secondary consumers (brown trout) eat primary consumers. Tertiary consumers eat secondary consumers. The great cormorant eats the brown trout (a secondary consumer), so it is a tertiary consumer.

Answer:

It eats a secondary consumer.