How Did Songbirds End Up In A Shark's Stomach?

“Backyard birds” are being eaten by young tiger sharks in the Gulf of Mexico. But how did these terrestrial birds end up in the sea in the first place?

Juvenile tiger shark, Galeocerdo cuvier, in the Bahamas. Is this shark a bird-eater? (Credit: Albert Kok / CC BY-SA 3.0)

A couple months ago, it was reported that juvenile tiger sharks along the Mississippi and Alabama coasts are eating birds (ref). But the surprise was the birds found in shark stomachs were not gulls or pelicans or other sorts of seabirds, but instead, they were birds that live in people’s backyards, such as wrens, swallows, doves and woodpeckers (Figure 1). How did those terrestrial bird species end up as a tiger shark’s lunch? This led the authors of that study to propose that the birds were migrating, became exhausted and fell into the sea before reaching land.