It’s a cloudless late-September day at Biddeford Pool, a tidal estuary 20 minutes south of Portland. Two rare red knots — a robin sized sandpiper — are foraging for marine invertebrates on mudflats exposed by a falling tide. Discovering these extraordinary long distance migrants is a bittersweet surprise. For a few moments I wish that ignorance were bliss. Aware of the precipitous decline of red knots overshadows my joy. Ignorance, of course, is not bliss but knowledge is a heavy burden when not applied to save an imperiled species.

I held one listless underweight adult male in my left hand. His fat reserves depleted, the knot had burned muscle mass during a grueling four days nonstop flight from Brazil.

The adult knots are traveling from the Arctic Circle, where they breed, to their wintering grounds at the southern tip of Argentina, a distance of 9,500 miles. In 1985, Atlantic red knot populations wintering in Argentina numbered 68,000 and adult survival rate was a healthy 85 percent. Today, the wintering population has plummeted to 13,000 birds and adult survival rate has dropped to a dangerously low 50 percent. Population models indicate that if adult survival does not improve, red knots will become extinct within 10 years.

Only one of the Biddeford Pool birds will likely survive to return to Maine next September. If the bird is blessed with strong genes and luck, it may reach the age of 16, not unheard of among red knots. At that age, the five-ounce bird will have flown 304,000 miles during its lifetime, the equivalent of flying to the moon and halfway home.

The U.S. Fish and Wildlife Service (USFWS), my employer for 30 years, has not yet added the red knot to the federal endangered species list. In the late 1990s, the agency sent me to New Jersey to learn about red knots and other declining shorebirds. I spent a week in late May studying knots with Dr. Larry Niles, a red knot expert, and other scientists.

The species is in dire straits because millions of horseshoe crabs are being commercially harvested as eel and conch bait by Delaware Bay fishermen. Horseshoe crab eggs are an important food source for thousands of spring migrant sandpipers. For red knots though, crab eggs are essential. It’s their lifeblood. For millennia, Mother Nature ingeniously synchronized knot springtime arrival dates in Delaware Bay with peak horseshoe crab spawning.

Crab eggs are the knots last energy source before a 48-hour nonstop flight to nesting grounds in the Canadian Arctic. Without caloric rich crab eggs, red knots struggle to complete the final 1,800-mile leg of a journey that begins in the southern tip of South America. It’s simple math: fewer horseshoe crabs means fewer eggs to fuel the knot’s migration. The red knot supermarket on Delaware Bay is under stocked and can no longer meet the needs of starving birds arriving in late-May.

We captured a few dozen red knots in a mist net on a New Jersey beach. I held one listless underweight adult male in my left hand. His fat reserves depleted, the knot had burned muscle mass during a grueling four days nonstop flight from Brazil. He weighed a mere 112 grams. Knots gorge on crab eggs for two weeks to increase their weight to 180 grams – a critical number required to reach and breed successfully in the arctic.

With sandpiper foraging competition intense for diminishing crab eggs, the late arriving red knot in my grasp stands little chance of successfully breeding even if he reaches Baffin Island in early-June. Many underweight red knots die if snow greets them in the arctic. They lack fat reserves to withstand prolonged periods of June precipitation, exacerbated by global warming. It’s similar to a stranded hiker clinging to life in the Maine woods in April with only a few granola bars and no winter coat.

Holding an emaciated red knot and feeling its heartbeat is profoundly moving. It’s like holding the invisible hand of Providence. That’s no small revelation for an agnostic. The bird had descended unseen from the heavens minutes before flying into our mist net. That he even reached New Jersey is miraculous.

Today, the red knot is a candidate species for federal protection, stuck indefinitely in a bureaucratic holding pattern. Plagued by an 80 percent population decline, the species may become extinct before it’s added to the endangered species list. Inattention to the red knot underscores a serious flaw of the Endangered Species Act. Rather than help the knot now when it would benefit the most, the USFWS is waiting for the crisis to worsen before acting. That rationale is analogous to ignoring an engineer’s plea to fix a twisted train track to prevent a crash. Ecological train-wrecks should not trigger conservation action.

A strong northwest gust lifts the Biddeford Pool red knots into the air. I lift my binoculars to watch the birds fly south overhead. They’re so close in my field of view it seems like I could touch them. In less than a minute, they disappear as climbing specks in an azure sky. I wish them Godspeed and pray the international conservation community responds to the knot’s urgent cry for help before it’s too late.

Ron Joseph, of Camden, is a retired Maine wildlife biologist.

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