Dolphins Now Can Use Shells to Hunt
By Colin Wang
Dolphins usually learn how to hunt from their mothers. The Indo-Pacific bottlenose dolphins in the Western Australia Shark Bay are distinct. Some of these dolphins learn skills from one of their companions. Researchers argued about this topic in the Current Biology that was posted online on June 25. Studies from before have shown that dolphins can learn from their associates. Cetaceans are a type of marine mammal that includes whales, porpoises, dolphins, and they are known to have tricks to help them get their meals. Humpback whales off the coast of Alaska use their fins and circular bubble nets to catch fish sometimes. The Indo-Pacific bottlenose dolphins in the Australian Shark Bay use sea sponges to protect their beaks while rooting a meal off the ocean floor, a trick they learn from their mothers. Some of the dolphins use another unusual tool reliant method of hunting called shelling. The prey will first be trapped in the shell of a large sea snail, the dolphin will stick its beak into the shell and then lift it above water to empty the contents of the shell into its mouth. The behavior appears to be unique to specific groups. From 2007 to 2018 Sonja Wild, a behavioral ecologist at the University of Konstanz, Germany and her partners documented 5,278 pods of dolphins encounters in the western gulf of Shark Bay with only 42 uses of shelling and only 19 dolphins using the tactic. The researchers examined 310 dolphins that had been seen at least 11 times which included 15 dolphins that used the technique. Wild’s team also mapped the dolphins’ network of interactions with other dolphins. The interactions explained why shelling spread better than other factors which “included genetic relatedness and the amount of environmental overlap between dolphins”, wrote Jack J. Lee, the author of the article. Wild likened the learning of this behavior is like the spread of a virus. The researchers estimate that 57 percent of them learned the technique learned from their companions rather than on their own. Researchers might be quick to dismiss the influence of a dolphins environment and what they learn from their mothers. The specific shell is only found in a specific region and dolphins that enter those locations will have access to the shells.