Bird Watcher's General Store

“A Cape Cod Destination Icon For 40 Years”

Great Black-backed Gulls

Dear Bird Folks,

Please take a look at the bird in this photo. Is it a gull, tern or plover? Thanks.

– Kate, Wellfleet, MA


It’s a gull, Kate,

The bird in your photo is a gull. It’s a Great Black-backed Gull to be exact, and I’m glad you asked about it. Gulls are the signature birds of our coastal community and yet they often go overlooked. In fact, you may be one of the first people ever to send me a gull photo. Each week I receive pics of songbirds, hawks, ducks, etc., but rarely any gulls. I find this odd since it’s hard to go anywhere without seeing a gull, or two or twelve. Yet, for whatever reason, gulls on Cape Cod are like the serving suggestions on a bag of chips…nobody seems to pay any attention to them.

Gulls are found all over the world, ranging from the Arctic to Antarctica and everywhere in between. There are over fifty other species of gulls worldwide, sporting such creative names as Armenian Gull, Lava Gull, Kelp Gull and my personal favorite, Belcher’s Gull. These birds and all the rest of them have one thing in common: they are all smaller than the bird in your photo. The Great Black-backed Gull, a species that breeds right here on Cape Cod, is the largest gull on the planet. It is the blue whale, the African elephant and the lowland gorilla of the gull world. No gull is bigger or badder. To compare them to more familiar predators, Great Black-backed Gulls are larger than Red-tailed Hawks, Ospreys and even the mighty Great Horned Owl.

Gorillas and elephants are basically vegetarians, but black-backs choose to have a more liberal diet. And by liberal, I mean they’ll eat anything they can swallow, and a few things they can’t. (Maybe that’s how the Belcher’s Gull got its name.) Their list of food choices includes such varied items as berries, insects, crabs, fish, mammals and other birds, including puffins (yes, puffins), which they swallow whole. They also have no trouble scavenging whatever happens to wash in with the morning tide. Other gull species also like to scavenge, but they all give way when a black-back arrives. The smaller gulls, including Herring Gulls, know their place and back off. They saw what happened to the puffins.

Even though Great Black-backed Gulls are high up on the food chain, it doesn’t mean they don’t ever have problems. There was a time when women thought gull feathers looked good on their hats. Can you imagine? As a result, thousands of gulls were killed in the name of fashion. I might not be the most stylish person in the world, but anyone who thinks a hat covered in gull parts looks attractive, might want to invest in a new pair of eyeglasses. As a consequence of the feather craze, gulls and similar birds were nearly wiped out. Then things changed. New laws protected the birds and also, we stopped burning trash in our backyards. Remember doing that, and what does it have to do with gulls? Instead of burning our garbage, we brought it to the dump and the gulls couldn’t have been happier. The change in fashion, combined with a steady source of dump food, allowed the Great Black-backed Gull population to rebound and soon they began breeding here in the Bay State.

With their hefty bodies and distinctive black backs, Great Black-backed Gulls are unmistakable…except when they aren’t. Some birds, such as chickadees, look exactly the same from the moment they step out of the nest, until the day they retire to Fort Myers. Black-backs don’t work that way. After a few weeks, young gulls become just as big as the adults, but they won’t yet have solid black backs. Instead, they’ll sport a speckled salt and pepper look. (You know how kids like to dress differently than their parents.) In addition, an adult’s beak is bright yellow, with the familiar red spot. The beak of a first-year gull is totally black, as if it was borrowed from a crow. And in case you are wondering, yes, black-backs are bigger than crows, and ravens, too.

It is these young, unskilled birds that are (or were) most often found feasting at the dumps. A non-birder friend of mine used to say how nasty “dump gulls” looked, as if it was the garbage that caused the birds to look that way. In fact, regardless of where it eats, it takes three years for a Great Black-back Gull to gain its distinctive plumage. This is when the gulls become mature, forget about the dumps and start thinking about breeding. Black-backs may be the king of the gulls, but their eggs and chicks still have issues with land predators. This forces the gulls to nest on isolated islands, including the islands off of Boston, Falmouth and Chatham, where their chicks are relatively safe. Ironically, the young of other smaller seabirds that also nest on these islands aren’t safe from the hungry gulls. It’s a complicated world.

The bird in your photo is quite large, Kate. Its plumage is mottled and its beak is solid black, so it’s safe to assume that this is a Great Black-backed Gull enjoying its first winter. It won’t transform into an adult for another few years. Perhaps then, when it finally shows its true colors, people will actually start noticing it. However, changing color won’t help the serving suggestions on a bag of chips. They will never get noticed…at least by me.