Role of Predation
Predation is the consumption of one organism by another. Predation is not only just one animal eating another, like a lion hunting a gazelle. But it is also a cow grazing on grass. Predator-prey populations depend on each other. Without anywhere to hide, the prey is vulnerable. Predators will consume prey and the prey is go extinct. Then, without anything to eat the prey will go extinct. It also has other effects. Without the predator, the prey will become overpopulated and take over the ecosystem.
Example 1: The nassau grouper prey on moray eels. And Moray eels hunt parrotfish. If the moray eel were to contract some disease, its population would decrease. As a result, the nassau grouper population would decrease because of the loss of one of its big energy sources. Also, the parrotfish population would “explode” or rapid grow because of the loss of a predator.
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Example 2: The anchovy population is controlled by the brown pelicans. If the brown pelican population were to decrease for some reason, the anchovy population would increase very quickly. In order to keep the anchovy population under control so that they do not take over the ecosystem, a new type of bird were to be introduced. This bird would prey on on the anchovy and the population size would decrease back to normal once again.
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Predator- Prey Relations
Example 1: Lionfish and damselfish form a predator-prey relationship. The lionfish is the predator in this relationship and the damselfish is the prey. Both organisms live in the coral reef.
Damselfish have a very large population and have been living in the coral reefs of St. Johns for a long time. Lionfish on the other hand, have recently moved to the area. Lionfish pose a threat to its ecosystem because it is a tertiary consumer and there are not many predators for it. Lionfish are known to be able to adapt to many different types of water and can be found in many different areas of the world. It is rather surprising that the damselfish population is as large as it is considering that lionfish have been known to be vicious predators that wipe out native fish. If the damselfish population were to decrease, the lionfish would have to search for another source of food. If the lionfish population were to decrease then many of the native fish would be able to repopulate.
Example 2: The nassau grouper and the barracuda are another predator-prey relationship. The nassau grouper is the prey and the barracuda is the predator.
Example 2: The nassau grouper and the barracuda are another predator-prey relationship. The nassau grouper is the prey and the barracuda is the predator.
The nassau grouper has a small population and is on a decline. The hunting habits of its predators, in particular the barracuda, has resulted in the nassau grouper being placed on the IUCN Red List as endangered. If the population of the grouper were to continue to decrease it would not affect the ecosystem very much. The barracuda, being the top of the food chain, would be able to eat many of the fish. If the barracuda population were to collapse then the grouper may have a chance to repopulate.