Overfishing is changing a lot about the ocean including how animals interact and hunt in the wild. According to new research out of the University of Exeter, researchers have found that dolphins in the Mediterranean have resorted to stealing the catch of fisherman due to struggling to find enough fish to eat.
The researchers looked into the relationship between dolphins and fishermen in the waters off northern Cyprus and found that when the cetaceans are present, nets are six times more likely to be damaged.
The dolphins often tear the nets to get at the prey, creating a dangerous situation for the dolphins as the research team believes that around 10 are caught by accidents each year, although admitting they believe that the number is an underestimate.
“It seems that some dolphins may be actively seeking nets as a way to get food,” explains lead author Robin Snape, of the Centre for Ecology and Conservation at the University of Exeter, in a statement. “This is probably driven by falling fish stocks, which also result in low catches – meaning more nets are needed and higher costs for fishers.”
The majority of fishers in this area of the Mediterranean are small scale and set nets roughly 1.2 meters (4 feet) tall on the seafloor to catch fish. The researchers found that in about 28 percent of fisheries, common bottlenose dolphins have learned that these nets offer up an easy meal, particularly where over-fishing is driving the fish stocks down.
It appears that there is a vicious cycle occurring in these waters. The overexploitation of the fish stocks means the dolphins have less food to eat and that the fishermen have to lay more nets, doubling down on the problem.
While investigating the impact that fishermen are having on dolphins in the region, the team also attempted to find a safe option to limit the stealing of the fishermen’s catch and destruction of the nets using acoustic pingers. Dolphins are known for their ability to problem solve and they quickly learned that the pingers acted as a beacon to where to find their next meal.
The best solution to the problem for both fishermen and dolphins is to better manage the fisheries in the region. By creating marine protected areas that will help provide nurseries and for fish to grow in population, it will also give dolphins the opportunity to catch fish naturally.