The answer is Fist hope I helped
Answer:
When starfish were removed from their environment, the species richness of that area went down. This was because the starfish ate the mussels, and when the starfish were removed, the mussels became abundant and preyed on many of the other species.
This experiment showed that the starfish were a keystone species. A keystone species is a species that has a low biomass but a large impact on the community they are living in.
Herons are very large birds, and due to their intimidating size, they have very little predators. They have a varied diet and consume many different prey (fish, snakes, amphibians, and probably many other small animals). If the population of herons would decrease, the population of the other organisms living in the same environment would increase since they would have a greater chance at survival (since they are not being eaten by the herons)
They may depend on PH of the water, nutrients, and sunlight.
