Predators And Prey Of The Bottlenose Dolphin

3 Pages 816 Words

Predators and Prey of Bottlenose Dolphins
In Shark Bay, Western Australia

Many people think that dolphins are able to live their lives free of constraints and worries that most animals must face. However, this is not the case. Dolphins are almost constantly on the lookout for their next meal, and sometimes they must travel large distances to find food. Also, sharks appear to be a major threat to dolphins, especially calves. Despite the apparent importance of food availability and predation risk, there have been no studies that have systematically addressed this problem.
The bottlenose dolphins of Shark Bay are perhaps the best studied dolphins in the world. Since 1982, members of the Dolphins of Shark Bay Research foundation have collected data on the social lives of the dolphins near Monkey Mia, where six dolphins visit the beach to be fed by people. The study has found that these animals have complex social lives with stable social bonds that may last a lifetime. The dolphins also show different patterns of habitat use. Some dolphins spend a lot of time in shallow seagrass areas while others prefer deeper areas in the bay. Why do dolphins use the habitats that they do? We still don't know, but research on other animals suggests that food distribution and the threat of predators are major factors in habitat choice.
Like most other populations of bottlenose dolphins living in shallow coastal environments, the dolphins of Shark Bay primarily feed on a wide variety of fishes. Some observations suggest that the dolphins may have different species that they depend on at different time of the year. Therefore, it is important that we understand how the distribution and abundance of fishes changes spatially (between habitats) and seasonally. The major predator in Shark Bay is the tiger shark, but great white sharks (like the one pictured here) are also seen in Shark Bay occasionally. Again, we know very little about the habits of these ...