Briefly describe an experiment that would allow you to test the hypothesis that increased predation by killer whales was the cause of the sea otter decline. Keep in mind the following key components of any good experiment: a control (something to which to compare the treatment), replication (do it more than once), and consideration of confounding factors (what differences other than what you manipulate in your experiment?).

Control environment having no fish, seal or squid only sea otter.

Explanation:

If a killer whale is present in the control environment means no food except sea otter so we can see a decrease in the population of sea otter because the killer whale feed on it. If a killer whale has more food available in the form of fish, squid and seal etc so they will not feed on sea otter and their population will be increasing with the passage of time but when the killer whale is present in an environment which has no fish, squid and seal etc to eat so they feed on the sea otter to survive and as a result the population of sea otter decline.

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