Underwater Cameras Discover How Dolphins Pull Off a ‘Crab Bait Heist’
Frustrated fishermen in Australia have long been robbed by dolphins — and now camera technology has shed more light on the situation.
Crab pots being lowered in Koombana Bay in Western Australia are regularly raided by bottlenose dolphins which love nothing more than swiping the dead fish used for bait.
Wildlife conservationist Rodney Peterson wanted to know more and so embarked on a two-year journey with the Dolphin Discovery Centre in Bunbury to find out the secrets of the crab bait thieves by placing five cameras underwater which captured remarkable footage.
Initially concerned that the dolphins would get caught in the nets, Peterson and his team discovered that the dolphins were using their long snouts, jaws, and teeth to pull bait out of crab pots.
“Dolphins are very smart, brilliant observers and forage for food all the time. Often, when they see an opportunity they will go for it, especially the mothers with calves,” filmmaker Axel Grossmann, who helped with project, tells Live Science.
Even when the crab bait was hidden underneath a pot or in a box, the cameras captured the dolphins flipping the traps over or opening latched boxes.
The remarkable footage has amazed dolphin behavior specialists, who say they have never seen this type of behavior in such detail.
“I’ve heard fishermen telling that dolphins were stealing their bait,” says Dr Delphine Chabanne. “But without actually seeing the video it’s really hard to tell.”
The researchers believe that the larceny is risky for the mammals lest they become entangled or injured, so they developed a dolphin-safe solution.
“We and some crab fishermen developed a mesh bait pouch with a metal hook that kept the bait closed in tight,” Grossmann explains. “The dolphins learned that it wasn’t accessible, so they swam off. It means we get healthier dolphins and happier crab fishermen.”
There is a school of thought that suggests the dolphins aren’t stealing the bait because they’re hungry — they’re just doing it for fun.
The researchers identified two dolphins in particular who appear to lead the bait heists.
“Calypso and Reggae, yeah, if it wasn’t for those two, crabbing would be pretty simple, really,” says Peterson in an explainer video shared by the Dolphin Discovery Centre.
But the new dolphin-proof crab bait pots might put an end to Calypso and Reggae’s fun.
Image credits: Dolphin Discovery Centre TV