Answer: symbiosis
Explanation: If too many herbivores live in a community, the predator population will decrease rapidly.
In some case, I would say the sea otter would be both a dominant and keystone specie. Sea otters are main predators and most often are at the top or near the top of the food chain (whales and sharks would trump them easily as the top predators), but in this specific situation, the sea otter is a keystone species. A keystone species is an organism that more often than not an ecosystem can not continue without. In this situation, without the sea otter to control the sea urchin population is grew out of control and caused the expulsion of the giant brown kelp and havoc for the spawning fish. Thus, the sea otter is a must.
Normally a 10× drop for each trophic level, so I'd say 2,000 kilocal.
You’ll have a decrease in ATP production
Relative humidity changes when temperature changes
