Attack of the whale-eating seagulls

No one thinks of seagulls as fearsome predators, but, down in Argentina, the birds are being blamed for the deaths of whales thousands of times their size.

Seagulls like to dive-bomb the whales when they surface for a breath and peck at their skin for a bite of delicious, nutritious blubber. This leaves the whales wounded, but that’s not what scientists think is killing them. Rather, it’s the fact that the gulls attack whale calves, separate them from their mothers and interrupt their attempts to eat, leaving them malnourished.

Whales do not have lips for sucking, so mothers expel a thick milk in the water for their calves to ingest. The babies need more than 100 litres of it per day.

"With each attack this process is interrupted, and it is a crucial moment for the growth of the whales," said Mariano Sironi, director of studies at Argentina's Institute for Whale Conservation.

In 2012, Sironi tallied 116 whales found dead in these waters, and all but three of them were calves. That mortality rate was up 100 percent from the previous year.

…The lack of nursing causes serious nutrition problems for the calves. Post-mortem studies have shown evidence of malnutrition, and this is a working hypothesis that needs to be confirmed with several studies," Sironi said. [AFP]