The Moonbird is alive. I refer, of course, to a red knot that is the subject of a book by Maine author Phillip Hoose. Red knots are medium-sized shorebirds that migrate from their arctic breeding grounds all the way to the southern tip of South America. If that sounds hazardous, you’re right. And we’re making it worse.
The full title of Hoose’s book is “Moonbird: A Year on the Wind with the Great Survivor B95.” B95 is the number designation on the orange leg band that was first attached to this particular red knot in 1995.
He was an adult bird when first captured, making him over 20 years old now. Because B95 has migrated so far for so long, he’s traveled a distance equivalent to the moon and halfway back. Thus, the moniker: Moonbird.
An early death awaits most red knots. Over the last couple of decades, their population has dwindled by almost 80 percent. Primarily this is due to the overfishing of horseshoe crabs on Delaware Bay. For eons, red knots have timed their migration to the egg-laying cycles of these prehistoric crustaceans, fueling up midway through their 9,000-mile spring flight to the arctic. But cut-up horseshoe crabs have become a cheap source of bait for mid-Atlantic fishermen. As the crabs disappeared, so did the red knots.
Overfishing is not the only reason for red knot declines. Other shorebirds are dwindling, too. Habitat loss is the chief culprit, as pollution and encroaching development have eliminated staging areas.
Climate change is wreaking havoc. Droughts have dried up wetlands and mudflats. Major storms such as Hurricane Sandy have devastated critical shorelines.
Shorebirds need to fuel up to make their long journeys. If you were flying your Cessna to Tierra del Fuego, you’d need to gas up a few times, too. This is where it gets tricky. Spring migration for most shorebirds takes them up through the middle of the country, but fall migration takes them down the Atlantic coastline where food is more abundant.
Southbound birds need to roost quietly during high tide in order to retain the fuel they’ve just consumed. These roosts are critical, partly because there are so few of them. Typically, roosts are exposed locations isolated from disturbance, with enough visibility to see predators coming. There are only about 80 tiny spots along Maine’s 3478-mile coastline that collect significant numbers of roosting shorebirds. The loss of just a few such roosts can have a destructive effect on the population.
But wait, there’s more. Many shorebirds employ an unusual survival strategy. Once the chicks are able to forage for themselves up in the buggy arctic, both parents leave so that they are not competing with their own offspring for food. When you see semipalmated and least sandpipers on the mudflats this time of year, most are adults with dull and worn plumage. Over the next week, you should start to see a transition to more brightly colored birds. Those are this year’s hatchlings on their first trip south. But how do they find their way without their parents to show them?
Maine researchers were among the first to distinguish that certain shorebirds are born with an instinct to visit the same staging areas as their parents. It’s genetically imprinted. This strategy works great, unless something happens to the habitat in any of the staging areas. Shorebirds are often unable to find alternative sites, even if they are just a short distance away. Instead, they will do their best in the degraded area, powerless to search for greener pastures. Incapable of putting on enough fat, whole flocks of birds are destined to run out of fuel and fall into the ocean.
With all this in mind, I take great care while walking mudflats in August. Shorebirds startled from their roosts use up energy that they will need for their flight to South America. I enjoy watching shorebirds from a distance, usually while they are feeding. I go no closer than reasonable binocular range. I avoid sudden or fast movements. As any clammer will tell you, shorebirds get accustomed to humans provided that there are no surprises. And no dogs. A rambunctious dog on the beach is the last thing a flock of shorebirds needs.
Even if we humans do everything right, it’s still a dangerous world out there. Falcons and storms take a big toll. Many red knots will die this year. So far, Moonbird isn’t one of them. He was spotted in Quebec on Aug. 2, southbound.
Bob Duchesne serves as a Maine Audubon trustee and vice president of its Penobscot Valley Chapter. Bob developed the Maine Birding Trail, with information at www.mainebirdingtrail.com. Bob can be reached at firstname.lastname@example.org.