Sharks: The Apex Predators of the Ocean

Aquatic food chain

Trophic Cascade

An apex predator is a carnivore that, in a specific environment, has few or no predators of its own (What Eats 2014). In the ocean, this is the shark. Sharks can feed on large animals without worrying about being attacked. This allows them to sit comfortably at the top of the food chain and in the center of the food web (What Eats 2014). When sharks are removed because of finning the rest of the ecosystem is thrown off balance, which is known as a trophic cascade. A trophic cascade causes population imbalance in other species in the ecosystem (Carpenter 2014). In this case, a decrease in the apex predators leads to an increase in the next trophic level, usually large mammals or fish, which are typically shark’s prey. The graphic on the right shows that with the removal of sharks, the next trophic level, seals, overpopulate and this destroys the lower trophic level. This pattern continues until the producer’s trophic level is either diminished or thriving. It is difficult to determine which level will vary because the number of trophic levels can vary in different ecosystems. It can be noted in both of the graphics that the ecosystem has a very fragile balance, and that every species from sharks to phytoplankton relies on the other to keep this in check. The removal of the apex predator can reshape the entire environment from top to bottom (Carpenter 2014). If we are not careful the lack of sharks will disrupt the natural order of the ocean.

Works Cited:

Carpenter, S. (2014) Trophic Cascade. Encyclopaedia Britannica. Encyclopaedia Britannica. (Date Accessed: February 20, 2014.) http://www.britannica.com/EBchecked/topic/1669736/trophic-cascade.

  

What Eats. (2011) Apex Predators. What Eats? What Eats? (Date Accessed: February 20, 2014.) http://www.whateats.com/?s=shark.