What is an apex predator PDF

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What is an apex predator?
‘APEX’ comes from latin and means peak, or top. An apex predator is a species that’s at the top of the food chain, and has no natural predators in their environment.

Getting scientific, apex predators are defined in terms of trophic dynamics. This refers ...

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What is an apex predator? ‘APEX’ comes from latin and means peak, or top. An apex predator is a species that’s at the top of the food chain, and has no natural predators in their environment. Getting scientific, apex predators are defined in terms of trophic dynamics. This refers to the basic process of transferring energy from one trophic level (the groups of organisms at the same level in a food chain) to the next in an ecosystem. Apex predators occupy the highest trophic level in any ecosystem. Trophic cascade is an indirect effect by predators that changes biomass, abundance or productivity of a population, community at successively lower trophic levels or trophic level across more than one link in a food chain. Top-down trophic cascade - predators influence the abundance or biomass of a population at lower trophic level. Example: the predator (tiger population) has direct effect on the abundance of prey (deer) population. By controlling the prey population, the predator indirectly influences the abundance or productivity at the producer level (grass). This type of indirect influence at lower trophic levels by predators is termed as top down trophic cascade Bottom up Trophic Cascade – space or nutrients influence the abundance or biomass of a population at higher trophic levels. Example: lack of space or nutrients of the soil may lead to poor productivity at the producer level (amount of grass, no of fruits, less fruits). This limits the number of prey population that will influence the number of predators. This type of indirect influence on higher trophic levels by lack of space or nutrients is termed bottom up trophic cascade.

APEX PREDATORS’ EFFECTS ON THEIR ENVIRONMENT Apex predators often have a significant impact on their habitat (when they are also known as a ‘keystone species‘). This comes in the form both of controlling prey density and restricting smaller predators, which in turn has knock-on effects on the regulation of disease, and maintaining biodiversity in an area. When apex predators are removed from or introduced to new environments they can cause what is termed ‘trophic cascades’ – wide-ranging effects on lower levels of the ecosystem. For example, when arctic foxes were introduced to sub-artcic islands, their predation of seabirds was shown to turn grassland into tundra, whilst the recent reduction in sperm whale numbers has caused an increase in the population of large squid.

WHAT DOES APEX PREDATOR MEAN? In the natural sciences, an apex predator is a predator that exists at the very top of the food chain. Unlike some other predators, it’s never preyed upon itself. Examples include polar bears, lions, crocodiles, and orcas. WHERE DOES APEX PREDATOR COME FROM? The term apex predator has existed since at least the early 1970s, when they were discussed in reports about marine life as something distinct from ordinary predators. But, why not just call them predators or top predators and be done with it? Like actual apex predators have a certain role in nature, the word itself occupies a particular linguistic niche. In this context, apex means something close to a summit or peak. This makes more sense if you visualize an ecosystem as a pyramid that sorts organisms into a tiered system. In this theoretical pyramid, each tier contains a grouping of animals that eats the animals in the tier below them. Within the constraints of this model, the apex predator would be at the very top. Able to eat other organisms, but never eaten itself.

Trophic cascade is an indirect effect by predators that changes biomass, abundance or productivity of a population, community at successively lower trophic levels or trophic level across more than one link in a food chain. Top-down trophic cascade - predators influence the abundance or biomass of a population at lower trophic level. Example: the predator (tiger population) has direct effect on the abundance of prey (deer) population. By controlling the prey population, the predator indirectly influences the abundance or productivity at the producer level (grass). This type of indirect influence at lower trophic levels by predators is termed as top down trophic cascade Bottom up Trophic Cascade – space or nutrients influence the abundance or biomass of a population at higher trophic levels. Example: lack of space or nutrients of the soil may lead to poor productivity at the producer level (amount of grass, no of fruits, less fruits). This limits the number of prey population that will influence the number of predators.

This type of indirect influence on higher trophic levels by lack of space or nutrients is termed bottom up trophic cascade....