What is Trophic Cascade?

In the ecosystem, from the predator to herbivore to primary producer has important role in the food web dynamics because everything in the nature is connected directly or indirectly with everything else.

What is Trophic Cascade?

The trophic cascade is a combination of two words- trophic which means feeding and nutrition or trophic level of the food chain; cascade means succession of stages, operations, processes or units. Hence, the term 'trophic cascade' has grown into a modern dictionary of inconsistent definitions that obscures clear meaning.

It is an ecological phenomenon arising due to addition or removal of an apex predator in a food chain and resulting changes in the environment due to alteration of in population of different species and related changes. Examples – Removal of wolf in North America led to increase in the population of herbivorous animals. Thus increasing strain on plants and leading to decrease in vegetation cover.

In other words, a top-down cascade is a trophic cascade where the top predator controls the population of primary consumer. Hence, the removal of predators which are at the top level of food chain can alter the food web dynamics.

Why is the predators considered as the important drivers of the Ecosystem?

The Predators play the important role of balancing the population of grazers in the trio-trophic interaction of Predator-Herbivore-Primary producer. In the cascade level of the population, lack of predators leads to overgrazing and local extinction of a dominant plant species, but a less palatable species replaces the first, keeping the ecosystem functionally intact despite the shift in species composition.

In other words, if predators can check then herbivore to primary producer can be checked. For Example: Fishing is an ancient occupation of human but the commercial fishing affected the aquatic ecosystem.

What is Deep Sea Trawling?

What will happen when top Predators removed?

In many cases, the trophic cascades have been started by the over exploitation of humanity, such as harvesting of top predators like wolves, lion, tiger etc. If top predators have been removed then it has a detrimental effect on the prey populations, primary producers and ecosystem processes. Therefore, it is very important to preserve and protect the top predators because this will preserve the structure and processes of ecosystem where they belongs to.

If ecosystem functions normally, then the predator gets easy services like food, fibre, fresh water, good quality air, good quality water and good quality soil.

Why is Biological Diversity important?