New research shows that the survival of whales and dolphins depends on the quality of their diets.
Researchers from the University of British Columbia (UBC) and University of La Rochelle (ULR) published a study yesterday showing that marine predators like whales and dolphins need to maintain a high-energy diet in order to keep up with their high energy prey.
“The conventional wisdom is that marine mammals can eat anything,” said co-author Andrew Trites, a marine mammal expert at UBC. “However, we found that some species of whales and dolphins require calorie rich diets to survive while others are built to live off low quality prey—and it has nothing to do with how big they are.”
By comparing the diets of 11 different species of whales, dolphins and porpoises in the Northeast Atlantic Ocean, the researchers found that differences in the size of the predators did not explain the differences in the quality of prey they consumed. The real explanation was found in the muscles.
“High energy prey tend to be more mobile, and require their predators to spend more energy to catch them,” explained Trites. “The two have co-evolved.”
First author and post-doctoral fellow at ULR, Jérôme Spitz, noted that the research will help scientists learn more about the impact of resource changes to marine mammals.
“Species with high energy needs are more sensitive to depletion of their primary prey,” explained Spitz. “It is no longer a question of how much food do whales and dolphins need, but whether they are able to get the right kinds of food to survive.”
To learn more:
- Read the full news release from UBC: Eating right key to survival of whales and dolphins
- Find the full study, published in the journal PLOS ONE, here: Cost of Living Dictates what Whales, Dolphins and Porpoises Eat: The Importance of Prey Quality on Predator Foraging Strategies
Copyright © 2012 by Marine Science Today, a publication of Marine Science Today LLC.