This is scientific Americans 60 second science. I'm Jason Goldman. Got a minute?

Gulls. You may have noticed that gulls can be pretty aggressive when it comes to grabbing food,

but that behavior is more intense than you may know.

Some kelp gulls snack on baby whales, live baby whales.

In the early 1970s, only a handful of southern right whales were fed upon by kelp gulls off the coast of Argentina's Peninsula Valdez.

Back then, just 2% of calves every year had to suffer at the beaks of the gulls, along with some of their mothers.

But now, 99% of the calves have to contend with hungry gulls, driving their hooked beaks deep into their backs,

ripping out chunks of skin and flesh and blubber, and gobbling it all up.

The finding is in the journal Ploss 1.

Each gull has its own whale and it protects it.

University of Utah biologist Victoria Roundtree.

Or maybe two gulls will have its own whale and they'll chase off any gulls that come in and

they just sit in the water and waiting for the whale to surface again, they're relentless.

Adult whales have learned to arch their backs when they surface to breathe, keeping most of their body

away from the hungry galls, but the newborns can't do that.

But you can see the mother is getting so annoyed when finally she's been able to sleep and

she isn't arched her back and she isn't horizontal to the surface and her calf is sleeping next

her and then a gall comes along in bambo.

I think the study I did in 98 showed that it took 30 minutes back then for them to return to normal behavior

and not do this avoidance behavior.

More than 600 calves died between 2003 and 2014.

Some years, at least a fifth of all newborns perished.

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