Piping Plovers, a type of shorebird. Credit: Bob Duchesne

It was a chilly walk down the South Lubec Sand Flats that August morning 11 years ago. Even in the middle of summer, a southerly wind can blow clammy on the clam flats. I wore a jacket. So did Lindsay Tudor, my birding partner for the day. We were nonetheless chilled, squinting through spotting scopes at distant shorebirds in the fog.

For nearly 30 years, Lindsay has been a biologist for the Maine Department of Inland Fisheries and Wildlife. Sad to say, she’ll be leaving the department soon, and it’s Maine’s loss.

Lindsay and I were on the mudflats to survey shorebirds. There were a lot of birds on the beach that day, but not nearly as many as were there a decade earlier. Nor are there as many shorebirds on the mudflats today as there were on that chilly occasion when Lindsay and I cut our way through the fog to count them.

Shorebirds are disappearing. Rapidly. Some species have declined by up to 90 percent. A 75 percent reduction has been recognized for several other species, and the overall shorebird population has been reduced by at least 50 percent during just the past 40 years. While birds worldwide have been disappearing because of climate change, habitat loss and environmental contaminants, no population of birds has crashed faster than shorebirds.

The Earth is approximately 4.5 billion years old. It’s changed a lot. Change happens. Species generally evolve and adapt to gradual change, but rapid change comes too fast, leading to extinctions. We’re in one of those cataclysmic change periods now. It’s called the Holocene epoch, which is Greek for “entirely recent.” The Holocene is basically the period of human-induced change since the last glaciers melted, or most of them did.

A month ago, I was in Glacier National Park in Montana. Scientists hired by the Department of the Interior, prior to the current administration, have predicted that all of the park’s glaciers will be gone by 2030. Farther north, the Athabasca Glacier in Canada’s Jasper National Park is North America’s most-visited glacier. Though it is 10,000 years old, the glacier has suddenly shrunk by more than a mile during the past century of planetary warming.

Science is complicated. It would be easy and wrong to blame the shorebird crash on climate change alone. Shorebirds migrate unusually long distances. During all that flying around and all that time spent in vastly different places, bad things happen.

Climate change clearly plays a significant role. The Arctic ain’t what it used to be. Rising sea levels swamp nesting areas. Warmer seasons allow colonization by invasive species. Conditions favor predators. The snow goose is a benign waterfowl, but as goose numbers increase in the warmer Arctic, they start to push out the shorebirds. The geese don’t necessarily harm the nests, but they force a defensive response from the shorebirds that allows other predators to sneak in and grab the eggs.

Historical hunting practices reduced many species. Though extinction has yet to be acknowledged, the last Eskimo curlew on the planet probably ended up on a dinner plate. They were abundant and easy to hunt. There were millions of them. It has now been 55 years since anybody has seen one.

Habitat loss certainly plays a key role, and that includes the loss of refueling stations. Many shorebirds feed along their migration routes, storing up enough energy to complete their travels. You can drive from Maine to Key West, provided there is a gas station every 300 miles. Take away just one of those stations, and your car rolls to a stop. Much has been said about the approaching annihilation of red knots, a shorebird that migrates from the Arctic to the Antarctic, refueling on the eggs of horseshoe crabs in the Chesapeake Bay region. But crab populations plummeted due to overharvesting, and migrating red knots have starved accordingly. Only a quarter of the historical population remains.

Maine is one of the most significant refueling stations. Our big tides and cold, food-rich waters put a shorebird banquet on the mudflats. We’ve known for decades that Maine has a special responsibility in helping shorebirds on their way. Shorebird habitat protection was enshrined in Maine’s Natural Resources Protection Act, which just celebrated its 30th birthday last week. That law is specifically why Lindsay and I were on the mudflats braving the bitter August cold 11 years ago.

Dozens of shorebird species are passing through Maine right now. Visit a local mudflat and marvel at this migration miracle while you can.

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