The boom of four iron cannons broke the relative silence of North Beach Island in Chatham on Sunday, heralding the start of another season of Red Knot trapping.
This important research effort is led by Stephanie Koch and Kate Iaquinto of the US Fish and Wildlife Service and Larry Niles of the Conserve Wildlife Foundation of New Jersey. These three led a team of fifteen or so seasonal techs and volunteers in this latest trapping effort, aimed at learning more about this declining shorebird with one of the longest migrations in the bird world.
I talked about Red Knots last week, but if you missed it, here’s a recap. Red Knots are medium sized, dumpling shaped sandpipers that nest in the high Arctic, and migrate through Cape Cod primarily on their southbound trip from July through November. If you see them now you can still catch their beautiful orangey-breasted breeding plumage before it fades to gray for winter.
Much of the research and conservation work on Red Knots has focused on their dependence on horseshoe crab eggs in the Mid-Atlantic States during spring migration, but the Cape is a critically important stopover in the fall, and we still have much to learn about how the knots, and especially the juveniles, are using this area and where they are going from here.
To answer these questions, the researchers have been putting “geolocaters” and coded leg flags on the knots that track their movements around the globe. While the flags require people to read them, the geolocaters track the birds wherever they go. The small device attached to one leg records data on day length, which algorithms convert into approximate latitude and longitude. The only problem is, you need to catch the bird again to download the data – knots are too small for even the lightest of satellite tracking tags.
So how does one catch a Red Knot in the first place? Well, that’s where the cannons come in. First, biologists spend days scouting the Knots’ high tide roosting spots, where they rest in tight flocks with other shorebirds until their preferred feeding flats open up again on the dropping tide. At these roosts, it’s possible to net hundreds of birds at once through a technique known as cannon netting.
Before the birds arrive, the crew camouflages a long net in the sand adjacent to the roosting spot. The front of the folded net is attached to heavy projectiles that will be fired from four buried cannons, bringing the net up and over the unsuspecting birds. Larry, Steph, and Kate have years of experience and take every precaution to protect the birds from injury. A string with flagging attached, known as, and I’m being serious here, the “jiggler,” is used to shoo the birds away from the danger zone near the front of the cannons. It’s one person’s job to crouch all day long at the other end of the jiggler and watch for birds in the danger zone.
Yet another important, and comically named job in Red Knot trapping is that of the “twinkler.” “Twinkling” involves very slowly and gently moving the roosting birds into the catch area without flushing them. It’s a nerve-racking job, because one false move by a twinkler could send the flock flying off to another roost, negating many hours of hard work by a lot of people.
So while the Twinkler and the Jiggler sound like rejected Batman villians, it turns out they are critical jobs in an important shorebird research project here on Cape Cod. I bet you didn’t know that when you woke up this morning.
