Keystone Species & Trophic Cascades

Front

What is a keystone species?

Back

A keystone species is a species that has a disproportionately large effect on its environment relative to its abundance. Its presence or absence can significantly impact the structure and health of an ecosystem.

Front

What role do predators play in an ecosystem?

Back

Predators help manage prey populations, which in turn controls the ecosystem's producers (vegetation). This balance is crucial for maintaining biodiversity.

Front

What is a trophic cascade?

Back

A trophic cascade is an ecological phenomenon triggered by the addition or removal of top predators, which leads to changes in the population sizes of species at lower trophic levels.

Front

What happens to kelp forests when sea otters are removed?

Back

When sea otters are removed, sea urchin populations can explode, leading to overgrazing of kelp forests, which can ultimately disappear.

Front

Define abiotic limiting factors.

Back

Abiotic limiting factors are non-living components of the environment that can limit the size of a population, such as space, water, and fire.

Front

What is a biotic limiting factor?

Back

Biotic limiting factors are living components of the environment that can limit population size, such as competition, predation, and disease.

Front

How do starfish affect biodiversity on rocky shorelines?

Back

Starfish are predators of mussels; their removal can lead to a 'monoculture' of one species, reducing overall biodiversity.

Front

What is the significance of sea otters in coastal ecosystems?

Back

Sea otters are considered a keystone species because they control sea urchin populations, which helps maintain the health of kelp forests.

Front

What is a consumer in an ecosystem?

Back

A consumer is an organism that obtains energy by feeding on other organisms, including plants (producers) and other animals.

Front

What is the difference between a predator and a prey?

Back

A predator is an organism that hunts and eats other organisms (prey), while prey is the organism that is hunted and consumed.