When you think about seagulls, ninja assassin isn't exactly the image that comes to mind. But according to a new study, kelp gulls (Larus dominicanus) in Namibia have devised a clever new strategy for finding dinner: eating the eyeballs of baby Cape fur seals (Arctocephalus pusillus pusillus). Nom nom.
It's tough to stomach and certainly gives new meaning to the beach-going birds' Finding Nemo catchphrase ("Mine!"), but observations like this can help us better understand how coastal birds – and all animals – react to the changing world we live in.
"Although it may appear gruesome or evil, this is just another form of adapting in order to survive," says marine biologist Dr Austin Gallagher, who led the study. Because a blind seal pup won't be able to avoid predators, find its mother or learn to swim, removing the eyes is a brilliant way to ensure your meal remains there for the picking (no pun intended).
"When you look at what this bird is doing in other parts of the world, it’s really impressive. They are the crows of the coast, [resourceful and adaptable],” says Gallagher. In fact, they've even been known to land on and consume the meat of Southern right whales when they come up for air. "To our knowledge, this is the first record of this [particular] behaviour, suggesting that it may be unique to our study area".
MORE: Watch baby seals enter the world
When a gull stares blankly at you on the beach, beady little eyes blinking, it's hard to think of it as a particularly smart animal. But they're incredibly quick learners. Just look at how fast they've mastered the art of stealing from us: robbing store fronts or snatching food on the fly.
In Gallagher’s study, the shorebirds were successful in about 50 percent of their attempts at eye removal. In many cases, once the seal was blinded, other gulls would join in as well, aiming for other soft, exposed areas like the underbelly, anus and genitals (lovely, we know).
"Foraging behaviour in kelp gulls is highly plastic [subject to change]," explains Gallagher, adding that in some cases, these adaptations are a response to human impact. This could very well explain what's happening in Namibia.
Successful conservation efforts have helped Cape fur seal populations recover over the years. Today, between 20,000 and 80,000 of the animals can be seen gathering to mate along Namibia's coastline. But an influx of seals isn't great for everyone. Combined with overfishing in the South Atlantic, the pinnipeds’ voracious appetites mean less food for other fish-eating animals like our gulls.
"Our study [supports] predictions for increased conflict between seabirds and seals off Namibia made nearly 25 years ago," says Gallagher.
Each pupping season, the seals bring a new, dense and predictable food source to the coastline. For the gulls, capitalising on their ability to change hunting strategy means they'll continue to get their fair share. "These types of observations are crucial to helping us ask future questions and design new studies,” says Gallagher. "And and they could even allow managers to make important, rapid conservation decisions if need be".
Editor's note: The photos below might offend the faint of heart or stomach. Scroll at your own risk!
Top header image: Cláudio Dias Timm/Flickr
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