I have seen laughing gulls drop down onto the backs of pelicans and try to grab fish as they fall from the edges of the pelicans’ pouches.

A pelican will fly high over the beach scanning for movement and then dive quickly down into the water, scooping up small fish in its pouch. Then it will lift its head to drain the seawater out of the sides of its pouch before swallowing its catch. That’s the moment when the laughing gull will try to snatch a fish.

I learned a catchy name for this behavior – kleptoparasitism.
The laughing gulls can be quite intrusive but pelicans are large birds, and an angry pelican can deliver a sharp bite with the hook at the end of its beak – though not when its mouth is full.

And when a laughing gull approaches from behind, it is hard for the pelican to get the gull off its back.

One passive pelican defensive strategy is to just keep its mouth closed until the laughing gull gets bored and goes away.

Another pelican strategy is to make itself look a big crazy turtle.

I find it hard to understand why the laughing gulls don’t just go catch their own fish. Are they just being lazy?
Maybe, but this behavior actually seems to be an evolved strategy. A pelican can dive deeper and get more fish than a laughing gull. So a laughing gull that is able to get some of the pelican’s fish without too much trouble can be more successful – eating better, conserving its energy, and having more time for mating, nesting, or defending its territory.

It is actually not just laughing gulls that try to steal fish. I once saw a huge frigatebird at Maho Bay attack a small tern sitting on a buoy until it gave up the fish in its mouth. That was a violent form of theft. Also, up north, bald eagles will grab fish from ospreys in a mid-air display of their superior strength.
The laughing gulls can’t take a fish from the pelican by force so, while annoying, they are probably not really scary. And, to an observer, they do look pretty funny riding on the pelicans.

Gail Karlsson is the author of a photo book Looking for Birds on St. John, as well as two other books about nature in the Virgin Islands – The Wild Life in an Island House, and Learning About Trees and Plants – A Project of the Unitarian Universalist Fellowship of St. John.  Follow her on Instagram @gailkarlsson and at gvkarlsson.blogspot.com. Website gailkarlsson.com