What is a trophic cascade simple definition?

Trophic cascades are powerful indirect interactions that can control entire ecosystems. Trophic cascades occur when predators limit the density and/or behavior of their prey and thereby enhance survival of the next lower trophic level.

What are some examples of a trophic cascade?

The otter-kelp example

Another frequently cited example of a trophic cascade involves the sea otter-kelp ecosystem of the rocky reefs of the Aleutian Islands in the North Pacific Ocean. In this ecosystem, the sea otter is the keystone species with sea urchins as its main food source.

What are the two types of trophic cascades?

There are two types of cascade: Top down cascades caused by the population decline of a top predator. Bottom up cascades caused by the population decline of a producer or primary consumer.

What is trophic cascade quizlet?

Trophic Cascade. A series of changes in the population sizes of organisms at different trophic levels in a food chain, occurring when predators at high trophic levels indirectly promote populations of organisms at low trophic levels by keeping species at intermediate trophic levels in check.

What is cascade effect in biology?

An ecological cascade effect is a series of secondary extinctions that are triggered by the primary extinction of a key species in an ecosystem.

How do you use trophic cascade in a sentence?

The result was unequivocal evidence that sea otters were at the head of a three-layer trophic cascade, a classic instance of ‘top down forcing’ by a keystone predator. Ecologists call the result a trophic cascade. This absence of the apex predator has led to a trophic cascade in many areas.

Which of the following is an example of a trophic cascade quizlet?

Which of the following is an example of a trophic cascade? A mass mortality of a species of bird results in increased numbers of herbivorous insects and decreased biomass of grass.

What is a top-down trophic cascade?

A top-down cascade is a trophic cascade where the top consumer/predator controls the primary consumer population. In turn, the primary producer population thrives. The removal of the top predator can alter the food web dynamics.

How is a trophic cascade different from a trophic pyramid?

Explanation: The energy pyramid, another method for understanding a biological system is by understanding the subject of trophic cascades. Trophic cascades found when the abundance of specific living beings are significantly influenced. A top-down trophic course happens when there is an removal of a top predator.

How does the story of the sea otter illustrate an example of a trophic cascade?

The otters were indirectly controlling the amount of kelp. A trophic cascade occurs when removal of one species (usually a predator) affects the abundance and distribution of species that it does not directly prey upon.

How does trophic cascade occur?

trophic cascade, an ecological phenomenon triggered by the addition or removal of top predators and involving reciprocal changes in the relative populations of predator and prey through a food chain, which often results in dramatic changes in ecosystem structure and nutrient cycling.

Who coined the term trophic cascade?

Famous wildlife ecologist Aldo Leopold first noted early in the 19th century that predators maintain a balance within an ecosystem. Marine ecologist Robert Paine coined the term ‘trophic cascade’ in 1980 to describe this phenomenon. Since then, our understanding of trophic cascades has expanded.

Can a trophic cascade be bottom-up?

Bottom-up trophic cascades at various levels. While top-down cascades have been generally examined by experiments removing top predators in food webs (Schmitz et al. 2000), bottom-up cascades have been detected as indirect effects of heterogeneity of plants on third trophic levels through herbivorous insects.

What is the difference between trophic cascade and keystone species?

An animal at the top of an ecosystem’s food chain – often a large predator – is called a keystone species. Removal of a keystone species disrupts the natural balance within an ecosystem; a disruption called a trophic cascade.

How can climate change set a trophic cascade in motion?

Warming directly accelerates individual metabolic rates [2–5,15,92], which causes increased feeding rates [10,15]. Over the short term, this can lead to increased top-down control and trophic cascades.

What is the use of and when characterizing a trophic cascade?

Answer: + and – represents top down cascade and bottom up cascade respectively.

What is a keystone species example?

Keystone species hold together the complex web of relationships in an ecosystem. They can be animals, plants or microorganisms. Examples of keystone species include starfish, sea otters, wolves and elephants.

What is a keystone species?

A keystone species is an organism that helps define an entire ecosystem. By keeping populations of mussels and barnacles in check, this sea star helps ensure healthy populations of seaweeds and the communities that feed on them—sea urchins, sea snails, limpets, and bivalves.