Conservation biologist Stuart Pimm joins citizen scientists–highly skilled amateur naturalists and their extraordinary organizer–on a New Jersey beach. The mission : Catch, band, and release hundreds of red knots, tiny birds that stop to rest and feed on one of the world’s epic animal migrations–the annual trek between the southern and northern extremes of the Americas.
This is a companion piece to Why the ultimate frequent flyer–the American knot–is endangered.
By Stuart Pimm
Reed’s Beach, New Jersey–It’s a perfect day, barely a cloud in the sky, and just enough breeze to keep the biting insects away. We sit on small folding cloth chairs. The conversation is relaxed but hushed –we don’t want to scare the birds that are coming onto the beach in front of the bushes behind which we hide.
I grab a sandwich. A lifetime of fieldwork teaches me to eat when I can. One never knows when the next chance will be.
Larry Niles and Clive Minton are the only ones to peer over the bushes. They are talking over radios to others on various beaches. “Move up.” “We may need to twinkle them.” “How many knot do you have?” “Do you see any loggers?”
It’s technical stuff.
People are being moved into place. The rising tide encourages the birds to leave other beaches and we are gently persuading them from other dry places where they might rest. We want them on our beach, please. If they are not in exactly the right place on our beach, they have to be encouraged to move a few feet–”twinkling.”
Larry also speaks into a speaker so that we can hear clearly what’s going on. We become ever more attentive.
Twenty of us are up on our feet and running as fast as we can toward a net that has been fired by three cannons over a mass of migrant shorebirds–knot mostly, but also turnstone and sanderling. At day’s end, we’ll know there are over 300 birds under the net. For the present, it’s just a lot of birds.
Setting the cannon net.
Photo by Stuart L. Pimm
Collecting birds from the net.
Photo by Stuart L. Pimm
There’s a lot of equipment to carry as we run, a lot to do in a very short period of time. Everyone knows exactly what to do.
This is very technical stuff, requiring a lot of different skills–from loading black powder into the cannons to getting samples that will tell us whether the birds are carrying bird flu.
It’s done almost entirely by an amazing group of amateurs. They have come from around to the world to be on the New Jersey shore for a few critical weeks. They are all repeat offenders. They have followed one man–Clive Minton–to literally the opposite ends of the Earth, season after season, some of them for decades.
Photo of Clive Minton by Stuart L. Pimm
I kneel in the wet sand getting birds from the net and reflect that I’ve done this before. The last time I helped Clive was 40 years ago on a cold, wet fall day on the east coast of England. So some history is in order.
Early last year, Clive e-mailed me, reminding me of that day. He’d seen that I was then still a member of National Geographic’s Committee for Research and Exploration and that we’d funded a project on migrating purple martins and wood thrushes run by Dr. Bridget Stutchbury. Clive wanted the details and her contact information.
By late May last year, the shorebird team was on the New Jersey beaches and attaching the 1.5 gram devices to the legs of 150 knots. These devices record the time each day when it gets dark or light. That gives a pretty accurate fix on where the bird is. Even in a few years, these devices have given extraordinary insights into where migrant birds go and how long they travel in single journeys.
The logger adds only 1 percent to the bird’s total weight. That’s an important consideration for the knot–it migrates from the very southern end of the Americas to the very northern end. But the loggers have to be retrieved from the bird before they can yield their vital data.
So a year later–last Thursday–I arrive at base camp on Reed’s Beach in New Jersey, hoping to be there on the day when they would catch one of those 150 birds and retrieve the data.
Clive and I catch up over dinner. He introduces me to the international crew–from Australia, Quebec in Canada, the UK, the Netherlands, the U.S., all volunteering their time to help Larry Niles and his wife Amanda Dey, who work for the New Jersey Division of Fish, Game and Wildlife.
The conversation is “birdwatcher English.” Here, shorebirds are “waders,” and we will “ring,” not band them.
Stuart Pimm’s video conversation with Clive Minton.
Sleeping accommodation is a mattress on the floor of an already crowded room. I’m speaking my native tongue, am thankful that it’s not simply a hard floor, and feel right at home.
Clive started ringing waders in the early 1950s, first using mist nets, then developed cannon nets in the mid 1960s. It’s the design we’ll use today and is used worldwide. The cannon shoot a net the size of a tennis court.
Because so many birds are caught at once, Clive needs a large team. Setting up the net requires digging the cannons in, folding the net, then carefully hiding it under the shoreline debris. It’s then armed and everyone retires to a safe distance.
Initially, the teams put on standard metal bands, but recovery rates were low. So from 1990, they put on additional colored leg flags. “That increased our data by twenty times. If we saw a bird in Brazil with a lime green leg flag, for example, we know the bird was marked in the USA.”
“But we didn’t know which individual it was. So, starting in 2003 in Delaware Bay, we added leg flags with letters on them–and that allowed us to know exactly which bird we were seeing through a telescope.”
“We see 70 percent of those birds in subsequent years. That’s with a big, dedicated team, scanning places systematically.
“Then, in 2009, we put data loggers on the birds.”
Now the task is to retrieve them.
Within seconds of “Fire!” we’re on the shore, rolling up the net. Others have covered it with a cloth to keep the birds cool. Yet others are bringing up cloth-covered boxes into which we put birds. “Knot” I shout, and one of the “knot boxes” comes by. There’s another for sanderlings. In minutes, all the birds are in boxes, in neat rows, one per species.
Stuart Pimm ringing a knot.
Photo courtesy of Stuart L. Pimm
Photo courtesy of Stuart L. Pimm
We organize into small teams, sitting in circles. I put a metal ring on each bird’s right leg and read out its number for Jannienne, to my right, to record. To my left, Amanda puts on a numbered leg flag, reads its letters and the metal band number, as a check. Jannienne writes that down. To Amanda’s left, someone measures the bird’s bill. To his left, someone weighs the bird, and so around the circle.
Everyone is telling information to Jannienne, who has to keep track of each bird separately. In a brief moment of calm, she tells me she’s from New Jersey and just wandered onto the shore one day–and volunteered.
Two hours later, we’ve processed and released over 300 birds. About 20 of the knot already have marks, one from 2003. It’s made at least eight round trips. If it had done that on an airline, it would be a very honored frequent-flyer.
The team packs up the gear, quickly, and we head back. No data loggers, alas, but the birds will be around another week. Some team members must go home, others have just joined. Some will be in the Arctic this summer, others will meet up this winter in Patagonia.
Back at base, the food tastes so good. We toast the two volunteers from Quebec who spent a long day on the shore and, through their telescopes, sighted 200 birds marked with leg flags in previous days and years.
Professor Stuart L. Pimm is a conservation biologist at Duke University, North Carolina. A former member of the National Geographic Committee for Research and Exploration, Pimm is the author of dozens of books and research papers, including the book “The World According to Pimm: A Scientist Audits the Earth.”