Relationships In the Ocean

Symbiotic Relationships

Symbiotic relationships in the ocean are important. Why? Not every organism can afford to compete for food or shelter. Not all organisms can co-exist. Symbiotic relationships occur between two different species and are non-competitive. There are four main symbiotic relationships; commensalism, parasitism, mutualism, and mimicry. In this interactivity, you will learn about symbiotic relationships. Click the player button to get started.

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Predator-Prey Relationships

Predator-prey relationships thrive on competition, so they are not symbiotic. A predator species will hunt, capture, and eat the prey species. Here one species benefits and one clearly does not. In a typical predator-prey relationship the number of prey affects the number of predators. If there is a large number of prey, then the numbers of predators will increase. Then, the number of prey will decrease and eventually so will the number of predators! This pattern is shown in the graph to the right. Notice that, as the prey species increases, so does the predator species. Then, when the prey species can no longer support the predator species and declines, so the does the predator species.

Sharks are predatory fish that eat a variety of ocean life. Since no other organisms (other than humans) hunt the shark, the shark is considered an apex-predator. However, competition within the species drives this relationship. The more sharks that exist in one area, the less a food source there will be. Predator organisms depend on other species to help them survive.

 

Relationships in the Ocean Review

Now that your have explored the relationships that exist in the oceans, check your knowledge. In this non-graded interactivity, read each description and then use the drop-down menus to select the matching term. Click SUBMIT to check your responses. Click the player button to begin.