What is a Trophic Cascade?
Trophic levels or feeding levels of organisms and effects on organisms at other levels.
Trophic levels or feeding levels, also termed trophic relationships, have been used to describe species interactions within an ecosystem based on the source of nutrients.
A trophic cascade is when the top predator in an ecosystem is removed, and it causes a chain reaction of events that alters the entire ecosystem.
The wolves In Yellowstone are a well-known trophic cascade example, when the last wolves were killed by human hunters in the 1930s, the elk were able to increase in numbers and over-graze the grasses, they also remained more stationary in areas and over-grazed the young willows. Beavers are dependent on young sapling willows to build their dams and as a result, the removal of all the wolves caused a declining beaver population.
The beaver dams also held back the stream waters, increasing the water height and flow out into the stream surrounds, raising the water table for water storage and use by plants and animals.
Species within ecosystems are classified as producers or consumers.
Producers or autotrophs, make the nutrients they need from chemical compounds and energy from their surrounding environment.
