What is the relationship between water clarity and otter survival?

Their survival is correlated to water clarity because kelp, the main food of otters' prey (sea urchins), needs clear water to thrive.

Explanation:

Otters are extremely important organisms, also known as "keystone" species. They keep aquatic ecosystems healthy because they control other populations such as sea urchin populations that consume kelp, sometimes in excess.

For this reason, otters prefer inhabiting near the kelp, which generally grows in clear waters near shores. They also prey on crabs, marine snails, squid, etc. as they possess the ability to dive as deep as 250 feet.

Therefore, their survival is correlated to water clarity because kelp, the main food of otters' prey (sea urchins), needs clear water to thrive.