![]() However, some adult whales have adapted their behavior to ward off their avian attackers. The gulls' feeding behavior has gotten progressively more aggressive through the decades, Rowntree said. As the whales raised their young over the next several months, the gulls would continue these attacks, pecking at the original holes to reach the nutrient-rich blubber under the skin until the holes widened into large lesions. The gulls are scavenging pieces of the whale's skin, which slough off as the animal hits the surface of the water, she added.īut in the early 1980s, a graduate student studying whales off the Valdes Peninsula in Patagonia (a nursery ground for southern right whales) noticed that some of the gulls also pecked at the whales as they breached, leaving small holes in the animals' backs. "Usually, when a whale breaches and leaps out of the water, lots of gulls will go chasing after the breach," Rowntree told Live Science. Things haven't gotten any better for the right whales since then, she said. In 1998, Rowntree and several of her colleagues published their observations of the gulls' morbid feeding behavior in the journal Marine Mammal Science. Off the coast of Argentina's Valdes Peninsula, right whale adults and their young are under constant attack by kelp gulls, a species whose population in that region has tripled in size since the 1980s, according to Victoria Rowntree, a research associate professor in the biology department at the University of Utah, who was not involved with the new study. Ī similar story is unfolding on the other side of the Atlantic Ocean, as well. As to why the seagulls do this, Gallagher said the reason is likely very simple: Seals are plentiful, fish are not, and gulls go for the meal that's easier to find. ![]() The kelp gull's taste for seal meat may be a new trend, but it's also possible that these birds have been plucking out seal eyeballs for a long time and no one ever noticed before, Gallagher told Live Science in an email. But there is good news: sometimes the baby seals escaped, at times receiving help from a larger, seagull-biting adult seal. Usually, other gulls would see the carnage and join in the meal, the researchers found. After consuming the seal's eyes, successful gulls pecked the bodies of the chubby baby seals, going for the soft, exposed regions of the underbelly and anus. Then, the gull went for the creature's eyes - rapidly pecking at the ocular region in an attempt to pluck out the animal's eyeballs and eat them.īut eyeball-eating didn't signal the end of the attack, the researchers said. A successful attack started when a gull approached a newborn seal that had wandered away from its mother or when the gull happened upon a sleeping juvenile seal. The scientists recorded about 500 eye-pecking attacks over the course of the 15-year observational study, and about half of those attacks were "successful," according to the researchers. By pecking out a seal's eyes, the gull renders its prey blind, making it tough for the baby animal to escape, said Austin Gallagher, a research scientist at the University of Miami and lead author of the new study. The gulls' eyeball-gouging sounds scary, but it's really just a clever hunting tactic, the researchers said. And they share the beach with several thousand breeding pairs of kelp gulls.Īs far back as 25 years ago, researchers studying the wildlife of coastal Namibia predicted that one day, the presence of both seals and gulls on the country's coast - mixed with the fact that overfishingwas steadily killing off both species' main food source - might lead to conflict. In the winter months, between 20,000 and 80,000 Cape fur seals make their home on this stretch of beach along the southern Atlantic Ocean. For 15 years, researchers have been keeping tabs on populations of kelp gulls and Cape fur seals at Pelican Point, in Namibia's Dorob National Park.
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