A Mesopredator is a mid-ranking

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

in a

trophic level The trophic level of an organism is the position it occupies in a food web. A food chain is a succession of organisms that eat other organisms and may, in turn, be eaten themselves. The trophic level of an organism is the number of steps it ...

, which typically prey on smaller animals. Mesopredators often vary in ecosystems depending on the

food web A food web is the natural interconnection of food chains and a graphical representation of what-eats-what in an ecological community. Another name for food web is consumer-resource system. Ecologists can broadly lump all life forms into one o ...

. While there is no definitive measurement for mesopredators, they are usually referred to as being medium-sized. This can depend on the size of the

apex predator An apex predator, also known as a top predator, is a predator at the top of a food chain, without natural predators of its own. Apex predators are usually defined in terms of trophic dynamics, meaning that they occupy the highest trophic lev ...

and the size of the mesopredator's prey. When new species are introduced into an

ecosystem An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the syste ...

, the role of mesopredator often changes; the same happens if a species is removed.

The Mesopredator Release Effect

When populations of

s decrease, populations of mesopredators often increase. This is the

mesopredator release effect The mesopredator release hypothesis is an ecological theory used to describe the interrelated population dynamics between apex predators and mesopredators within an ecosystem, such that a collapsing population of the former results in dramaticall ...

. These mesopredator outbreaks can lead to declining prey populations, destabilize communities and even drive local extinctions. When apex predators are removed from the ecosystem, this gives the mesopredators less competition and conflict. They are able to catch more prey and have lower mortality rates. Often mesopredators can take over the role of apex predators. This happens when new species are introduced into an ecosystem or when species leave or are killed off. Former mesopredators are not ecologically identical to the former apex predator (likely being a smaller species) and will have different effects on the structure and stability of the ecosystem. All mesopredators in the ecosystem benefit from this mesopredator release. Apex predators reduce mesopredator populations and change mesopredator behaviors and habitat choices by preying on and intimidating mesopredators. This occurs in any ecosystem with any type of relationship between predator and prey. However, in the case of the relationship between apex predator and mesopredator, it could mean that the apex predator causes the mesopredator to leave the ecosystem, creating room for new species to become mesopredators. Meso predators can become apex predators in new environment Mesopredator outbreaks are increasing in

fragmented habitat Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment (habitat), causing population fragmentation and ecosystem decay. Causes of habitat fragmentation include geological process ...

s. The main cause of this is the disappearance of apex species within the habitat. Apex species are usually larger animals requiring a bigger area and often leave if the habitat is lost. When the apex predator leaves the ecosystem, a former mesopredator will become the new apex predator. In addition to this, apex predators, being larger animals, often have more encounters with humans, leaving them more susceptible to harmful conflicts. These harmful conflicts can cause the apex predator to leave the ecosystem in fear of danger. If the situation is extreme enough, humans can kill off the apex predator population entirely. Mesopredator outbreaks are also becoming more prevalent as certain resources consumed by these species (such as pet food, trash, crops, and crop pests), are being added in fragmented areas. These resources often appear when development is occurring on land near or within the ecosystem, creating ideal conditions for mesopredator outbreaks to occur.

References

{{Reflist Ecology

The Mesopredator Release Effect

See also

References