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Transient Gull Sharks Use Clever Tactics to Catch Prey Off Chatham


Dear Bird Folks,

My cousin Frankie has been working on a Chatham fishing boat for the past fifteen years. During that time he has seen his share of interesting things. But this week he saw something that he’s never seen before. Just off Chatham’s outer beach there’s been a growing pod (school, herd?) of sharks. First he saw ten of them, then thirty and yesterday he said that there were easily over forty sharks out there. One old captain claims the sharks are looking for birds. Sharks looking for birds? Have you ever heard of this?

– Paul, Harwich, MA


It’s a shiver, Paul,

A group of sharks is called a “shiver” (not a pod, school or herd). A shiver of forty sharks sure seems like a lot, but apparently Chatham has now become the shark capital of the East. Plus, I’m not about to argue with anyone called “cousin Frankie.” He sounds more like a bouncer or someone who collects unpaid loans. The other reason I’m not going to argue is because the reports are true. There are indeed a lot of sharks off of Chatham and they really are looking for birds. Scientists refer to this species as Terra Nomadis Pistrix, aka, Gull Shark, because, as their name suggests, these creatures really, really, really like gulls. And who can blame them? Eating a bird that comes pre-stuffed with French fries is the perfect meal. (I’m surprised someone from Texas hasn’t thought of it already.)

The Latin name, Nomadis, tells us that Gull Sharks are great wanderers. They search the oceans of the world looking for colonies of gulls. Most of the time they swim along the coast of South Africa or in the waters off Argentina, where the locals call them “Topo Gigios.” But every few decades they get bored and venture north. Gull Sharks haven’t been seen in Massachusetts since the spring of 1955. It was thought the storms of the previous fall (in a particular, Hurricane Carol) carried them to New England. This year’s string of super-storms has once again brought these great predators to our shores, and Cape Cod’s gull colonies are in trouble. How could sharks bother nesting gulls, you ask? That’s where the “terra” part of their Latin name comes into play. (See, studying Latin wasn’t such a waste of time after all.)

Gull Sharks are the only sharks that have the ability to leave the comfort of the sea for brief periods, hence the name terra (as in terra firma). It’s been well documented that sharks have an underwater sense of smell, but these particular sharks take the smelling thing one step further. Gull Sharks patrol the coastlines of the world actually sniffing the air for gull colonies. (If you have ever been near a gull colony, Paul, you’ll understand how the sharks can smell them.) The colony that these sharks have zeroed in on is a huge settlement of Herring Gulls that have started nesting on Fiction Point, a newly formed sandbar off of Chatham Light. But sniffing the air for food is nothing compared to what happens next.

As the gulls go about building their nests, the sharks patiently wait offshore. Hanging around doesn’t bother sharks one bit. (It’s not like they have a tight schedule or anything.) What the sharks are waiting for is the spring high tide. The extreme tide will bring the water to the edge of the colony and that’s when the sharks get down to business. At the right moment several young sharks (still nearly ten feet long) will purposely beach themselves near the colony. Gulls are normally afraid of sharks, but not when they’re on land. Now the birds treat the sharks just like they would any other washed-up creature. They’ll gather around the “helpless” sharks and begin to pick at them, looking for soft spots, which are usually the eyes. Then things get crazy. (BTW: The following is pretty gory, so you might want to send the kids to bed and continue reading with your eyes closed.)

In an amazing act of split-second timing and coordination, the supposedly dying sharks come to life. With one sweep of their giant tails, the sharks instantaneously knock rows of clueless gulls into the sea and into the waiting jaws of their hungry relatives. For the next few minutes the ocean is a scene of flying feathers and burping sharks. But that’s not the end of it. As you can imagine, the feeding frenzy attracts gulls from all over, so the “land sharks” quickly quiet down and “reset” themselves back into washed-up mode. The arriving gulls descend upon what they think are dead sharks, only to get tail-slapped into the water and chowed down by a shiver of hungry Terra Nomadis Pistrix. The whole wild scene can last for over an hour or until the gulls finally catch on. At this time the sharks merely wriggle back into the water and move on in search of another colony. (If you have any friends that are gulls, you might want to blast them a text message or something.)

A few of these Gull Shark attacks have been posted on YouTube, Paul, but most of them are rather poor quality. Hopefully, news crews will get a better video this time, especially since we know when it will take place. According to the local expert, Ms. B. Ogus, curator of the Pistrix Institute (FYI: Pistrix is Latin for sea-monster, in case you didn’t know), the Gull Sharks should make their move at the peak of the spring high tide, which is this Monday, at 11:30 AM. The best (and safest) place to watch this rowdy event is from the public parking lot in front of Chatham Light. So pack your camera and binos and get ready to see nature in action. It all happens this Monday, April 1st.