Question

monterey bay is known for having very high biodiversity. its thick kelp forests work kind of like rainforests do on land, providing food and shelter for many organisms. the food web in this ecosystem includes species like sea otters, crabs, sea urchins, and small fish. which two changes would most likely cause the sea otter population to decrease in monterey bay?

Explanation:

Step1: Analyze the food web

The food web shows the relationships between different species. Sea otters are affected by their predators (sharks) and their food sources.

Step2: Consider the impact of changes

• Increase in shark population: Sharks are predators of sea otters. An increase in shark population would lead to more predation on sea otters, thus decreasing their population.
• Decrease in small fish population: Small fish are part of the food web. If small fish decrease, it can disrupt the balance. Sea otters might face more competition for other food sources (like sea urchins) if their prey base (small fish, etc. in a broader sense of the ecosystem balance) is affected. Also, a decrease in small fish can lead to a decrease in crabs (as small fish are food for crabs in the web shown). If crabs decrease, and if there are cascading effects (e.g., if algae - small fish - crab - some other indirect relation to sea otter's food availability or habitat quality through the overall ecosystem health), it can impact sea otters. Another way: if small fish (a part of the prey base in a more general sense of the ecosystem's productivity that supports sea otters) decrease, the overall health of the ecosystem (which sea otters depend on for food, shelter etc.) can be affected.

Answer:

An increase in the shark population and a decrease in the small fish population.