Answer:
increase; decrease; increase; decrease
Explanation:
When Lake Mendota was completely covered with algae, biologists used the concept of trophic cascades to solve the problem by introducing predatory fish. When they did this, an increase in predatory fish caused a decrease in plankton feeding fish, which resulted in an increase in herbivorous plankton with a consequent decrease in algae.
With the introduction of predatory fish, a decrease in the population of zooplankton-eating fish would occur due to predation by the newly introduced fishes. This will cause the population of zooplankton to thrive or increase.
Zooplanktons feed on algae. Hence, an increase in their population will put pressure on the alga in the ecosystem and cause a decrease in their population.
