Tiger sharks have long had a reputation for being opportunistic feeders that aren’t picky about what they end up eating. Everything from sea turtles to tarpon to license plates seems to be on the menu for this predator.
A new study found a surprising favorite snack for tigers — birds. Not just any birds like shoreline dwelling birds like gulls and pelicans but common backyard birds like sparrows, woodpeckers, and doves.
Lead author of the study, which was published in the latest issue of the journal Ecology, Marcus Drymon of Mississippi State University was part of a team of researchers who analyzed the contents of juvenile tiger sharks stomachs by inducing regurgitation. In 105 sharks they studied, 41 had bird remains in their stomachs.
“Tiger sharks will see an easy meal and snatch it up, but I was surprised to learn that the sharks were eating songbirds—I assumed that they’d be seabirds,” says Kevin Feldheim, a researcher at Chicago’s Field Museum and a co-author of the study who led the DNA analysis that told the researchers what kinds of birds the sharks were eating. “It was one of the coolest projects I’ve been associated with using DNA to tell a story.”
This isn’t the first time that tiger sharks have been known to eat birds. “There’s a site off Hawaii where baby albatrosses learn to fly, and adult tiger sharks pick them off,” explains Feldheim. But this is the first time scientists have evidence that tiger sharks eat songbirds that primarily live on land. That’s because these sharks were in the Gulf of Mexico, during migration season. “In every instance, the timing of the tiger shark eating the bird coincided with the peak sighting for that species of bird off our coast,” says Drymon.
“The tiger sharks scavenge on songbirds that have trouble flying over the ocean. During migration, they’re already worn out, and then they get tired or fall into the ocean during a storm,” adds Feldheim.