Spring brings a restlessness of soul that is nearly unbearable. For some species, the only way out is to flee. To move via walking, crawling, swimming, or flying. Millions of birds, animals, and even insects are compelled by a biological need to get into gear and migrate to a safe and plentiful location to introduce the next generation.
Bowerman Basin, a section of Grays Harbor National Wildlife Refuge in Hoquiam, Washington, is home to one of the most spectacular displays of this primordial devotion on the whole West Coast. Bowerman Basin is a calm and inconspicuous tidal mudflat on Grays Harbor’s north coast most of the year. Then, all of a sudden, in late April, it’s centre stage for 250,000 pacing, probing, peeping shorebirds. The next day, the total might reach 500,000.
For two weeks, flocks arrive, fatten up at Bowerman, and then depart to make way for the next wave. Up to a million shorebirds may have feasted on the mudflat’s abundant worms, snails, and other edible invertebrates before it’s through. The birds then vanish as quickly as they appeared.
High tides are essential for shorebird watching here. Bowerman is the last spot in Grays Harbor to flood during high tide and the first area to be exposed when the tide recedes. This allows birds to spend as much time as possible feeding in the rich mud.
I thought I was being very clever the first time I went to Bowerman to view the migrating horde by planning my trip around the lowest tide. I awoke in the middle of the night, drove two and a half hours, and arrived at Grays Harbor at low tide, just before the sun rose. I reasoned that the more mudflat exposed to hungry birds, the better. Good concept, lousy execution. The location seemed to be deserted. Almost all of the 400,000 birds I knew were there had followed the receding water and were feasting on the flats. I could have been staring at eraser dust. Of course, high tide brings the shorebirds together and up into the basin, where they may be seen. High tides, in particular, force the masses of birds to within roughly twenty feet of observation areas—so near that their restlessness is infectious.
When I informed a scientist with the US Fish and Wildlife Service about my humiliating blunder, all he answered was, “Well, at least you had a plan.” Some individuals, it seems, arrange their trips to coincide with the conclusion of Sunday lunch, which does not qualify as a plan since it does not take the tides into account. Other individuals plan their trips around the calendar, which does not qualify since birds cannot read and are notorious for arriving late or early. Make a strategy, call the refuge, and check the tide book.
Bowerman Basin is the northernmost of four shorebird “staging sites” on the continental United States’ West Coast. Staging zones are places where migratory birds gather and eat throughout their migration. Other major staging grounds in the Lower 48 include California’s Humboldt and San Francisco Bays, as well as Washington’s Willapa Bay. Most birds do not stop again after Bowerman Basin until they reach the Copper River Delta in Alaska, while some may linger at the Fraser River Delta in Canada and the Stikine River Delta in Southeast Alaska. Once in Alaska, shorebirds spread out throughout the state’s north and west coastlines to nest.
The majority of the migrants you’ll see at Bowerman are sparrow-sized western sandpipers. These small birds fly from Argentina to Alaska, usually at night and virtually in orbit—two miles high at times. It scares me to death just thinking about it.
Shorebirds only perform like way during their spring journey northward, so don’t expect a repeat engagement. Individual birds leave for wintering sites in North, Central, and South America at any time from June to October on their way south.
The name shorebird refers to tiny birds that wade but do not swim. Shorebirds may be found on almost any coast, including interior lakes and marshes as well as ocean beaches. There are sixty sandpiper and sandpiperlike bird species, a dozen plovers, and a vast mix of others in the western states alone, including oystercatchers, avocets, stilts, snipes, curlews, and phalaropes (the one exception to the no-swimming rule).
This year, on my way into Bowerman a half-hour before high tide, I observed a Peregrine Falcon preening on a gnarled piece of driftwood. Peregrines accompany the shorebird migration north, munching on downy hors d’oeuvres.
A merlin raced over and strafed the feeding throng, pulling a thousand sandpipers off the mud into a tight-formation flying team, ignoring the peregrine. What was on the ground a swarm of small brown birds with white bellies transformed into a silvery school of tropical fish in the air. The flock veered, twisted, flashed white, twisted around on itself, flashed brown, and dropped back to earth to avoid the little falcon. The shorebirds had come to eat. Because the falcon’s death-defying acrobatics were a diversion, the flock spent as little time as possible with him.
“Fat Power,” if shorebirds had a catchphrase, would be it. Gaining and properly using fat stores is critical to their success. Fat from the Bowerman Basin feast may easily sustain the birds for the final 1,500 kilometres to Alaska. Fat is reported to have almost as much energy as gasoline per gramme, twice the energy of protein, and eight times the potential energy of stored carbs. This high-octane fuel fuels a bird’s unique respiratory and muscular systems, resulting in a small yet efficient flying unit.
Many other smaller bird species are also energy efficient. According to at least one scientific publication, a Blackpoll Warbler would get 720,000 miles per gallon if it ran on gasoline. I couldn’t locate the supporting figures, but I couldn’t stop myself from repeating the assumption.
A bird’s traditional lungs are supplemented by additional air sacs that branch out into its hollow bones, increasing oxygen exchange and controlling internal temperatures. Birds have the greatest operating temperatures of any animal, averaging over 110°F. According to biologists, a pigeon utilises around one-quarter of its air intake for breathing and three-quarters for cooling.
In a metaphorical sense, it has always been evident that birds have a lot of heart, and physiology backs this up. Birds have a heart-to-body weight ratio that is three to six times that of humans.
Our interest in birds and their behaviour precedes the Audubon Society by millennia. Aristotle wrote out his own views and ideas on migration over 2,300 years ago. Some of his theories were spot on, while others were far-fetched, and both endured for two millennia. He was the first to notice vertical migration, which occurs when birds move heights depending on the season. But he also believed in transmutation, an alchemical concept that saw Redstarts transform into Robins over the winter.
Other theories emerged as time passed. A “Person of Learning and Piety” authored “An Essay toward the Probable Solution of this Question: Whence come the Stork and the Turtledove, the Crane and the Swallow, when they Know and Observe the Appointed Time of their Coming” in 1703. The likely answer stated was that birds flew to the moon. Perhaps the writer was sitting in his yard on a spring night when he spotted shadows of migratory birds passing in front of the full moon. The sight may nevertheless inspire awe, if not piety.
Although scientists have learned a lot about where birds migrate, they still don’t know what causes migration or how birds find their way. Photoperiodism (reactions to shifting daylight hours), weather, hormones, and food availability are all potential indicators that the migration has begun; and the moon, stars, and constellations are all possible indicators that the migration has begun.
The functions of landmarks, the sun’s angle, and the earth’s magnetic field in bird navigation have all been studied.
The quarter-million birds tattooed on the mud at Bowerman Basin were not leaking any secrets, but I did discover from fellow bird watchers that the majority of the birds had just flown in continuously from San Francisco Bay. I’d also heard that researchers had tracked the radio-tagged corpse of an unfortunate sandpiper to a ground squirrel tunnel in the Bay Area. The Fish and Wildlife Service volunteer who was telling the tale anxiously moved her hand-held antenna and twisted the reception dial for five more frequencies. Perhaps the tagged birds she was hearing had merely taken a break at an undisclosed rest stop along the road.
The shorebirds became thrilled as the tide receded and launched themselves out across the exposed mud. The 40,000 Dunlin that winter at Grays Harbor must have been perplexed. As a swarm of bills sought for food, a quiet hiss erupted from the feeding mass. Shorebirds generally consume amphipods (small, sandhopper-like crustaceans) from Bowerman’s abundant supply, but they also consume other tiny crustaceans, clams, and marine worms. Flocks moved about, flying low to the earth like dust on a road.
Because shorebird bills vary in length and shape, different species can work the mud next to each other without competing for food—neighborliness through niche (in natural science, the term niche refers to an animal’s ecological role or place within the food web, not to the rock, cave, or hemisphere in which it lives: a niche for everything, and everything in its niche). Nature, when it wants to be, can be rather neat.) Because each style of shorebird bill—long, short, upturned, downturned, straight, or anywhere in between—is intended to exploit a distinct stratum of mud, there is typically enough food for everyone. Invertebrates such as insects and their larvae, tiny crustaceans (shrimp, crabs, barnacles, and sand fleas), small mollusks (snails, clams, and mussels), and marine worms are found throughout the substrate.
Mudflats are one of the world’s richest ecosystems in terms of pure biomass. In one square yard of Bowerman Basin muck, there are as many invertebrates as there are persons in Grays Harbor County.
Bowerman is an excellent spot to learn your pipers from your plovers in the spring, thanks to its richness and variety of shorebirds. The port is frequented by two dozen species ranging in size from the five-inch Least Sandpiper to the eighteen-inch Whimbrel. Western Sandpipers are by far the most numerous, followed by Dunlins, dowitchers, Semipalmated Plovers, and Least Sandpipers.
Take out a log, prop open your book, and concentrate on the details. It’s a Western Sandpiper if it’s six or seven inches tall, has a brown back, white belly, and rust-colored head, and is clearly in the majority. You may be staring at a major fraction of the whole Western Sandpiper population right from your driftwood davenport.
This makes me as uneasy as thinking about their late-night trips. Storms carried a slick of oil from a huge disaster off the coast into Grays Harbor around Christmastime in 1988. Fortunately, hardly much oil made its way into the Bowerman Basin. However, if it had, the heavy crude would have killed the creatures dwelling in the mud, resulting in three staging regions along the whole West Coast. What if the leak had happened in April?
Sandpipers are brownish birds with white bellies that travel carefully down the coast probing the dirt. If it’s not a Western but is a sandpiper, it might be one of Grays Harbor’s seven sandpipers. Birders refer to the three smallest species as “peeps” (Western, Least, and Semipalmated).
Dunlins have somewhat drooping bills and are slightly bigger than Western Sandpipers. Dunlins wear black belly patches in the spring. They peck and run, peck and run, peck and run, peck and run, peck and run, peck and run, peck and run.
Dowitchers are one of the most frequent big shorebird species. The ten- to twelve-inch-tall birds use their two-and-a-half- to three-inch-long beak to probe the muck in a sewing machine action. They may have rust-colored bellies in the spring.
Semipalmated Plovers are very widespread. These seven-inch-tall birds skip readily over the soft mud, feeding on surface creatures with their partly webbed (semipalmated) feet. Plovers are constructed more compactly than sandpipers, with robust necks and pigeon-like eyes. Almost all of them, including the well-known Killdeer, have the run-stop-look behaviour.
It’s a phalarope if it can swim. Phalaropes like spinning like tops in the water, stirring up food from the bottom.
Bowerman Basin has wonderful bird watching opportunities, although it is hardly a wilderness experience. On the drive in, the log yard and smoke stacks of the Hoquiam lumber mill dominate the view. After parking, you walk (usually behind someone else) via a tiny airstrip to the route that leads to observation places. In US Fish and Wildlife Service pamphlets, the word “trail” is always surrounded by quotation marks. This is due to the fact that the route that skirts the mudflat out to the end of the spit is essentially a trail hammered down in four-foot-tall marsh grass. The route sometimes vanishes under five inches of dark sludge. It’s always muddy. Bring knee-high boots and be prepared for rain. But don’t forget to appreciate the surrounding landscape, which is eerily beautiful in sections where dark woods and free-flowing rivers still attract Black-tailed Deer, coyotes, Osprey, Great Blue Herons, steelhead, and salmon.
I had muck up to my hip pockets before I could name Semipalmated Plover when I stepped off the road into the “path.” I was slogging along when I saw a Marsh Wren sitting about eye level in the thick, stiff grass. I peered down its pink neck as it sung me past. I reached the point of the spit, where the beach firmened, by crossing the shorter salt grass. Old pilings snarled like evil teeth across the basin’s mouth, while Dunlins ran back and forth across the frothy lip of the retreating tide.
Prior to the leak, Congress approved the creation of a National Wildlife Refuge in Bowerman Basin in 1988. Four years later, the US Fish and Wildlife Service had bought 68 acres from the City of Hoquiam and was negotiating an additional 1,400 acres of marsh and mudflat with the Port of Grays Harbor. The development of the refuge (a visitors’ centre, habitat restoration, boardwalks, interpretive signage, and other amenities) is pending the receipt of more money and the eventual purchase of property. For the time being, the Port is generously permitting public access.
Grays Harbor has already been filled in by thousands of acres. Bowerman Field Airport, including the parking lot and the road you walk on, is built on dredged sediments placed on the tideland.
As the tide ebbed, the feeding shorebirds sorted themselves out: Lesser Sandpipers stayed high on the exposed mud, Westerns and Dunlins spread out below, and Dowitchers kept their feet wet. The late-morning light drew rich, saline odours from the dirt.
A Peregrine Falcon circled high in search of quick meal. Ground squirrels were on the loose in San Francisco as a cold front moved in from the north. A swarm of Western Sandpipers peered and whistled at the water’s edge, appearing much too vulnerable. I want to load all 250,000 of them into a bus.
- When to Go: The peak season for migratory shorebirds in Bowerman Basin is mid- to late April. The best time to visit is one hour before or after high tide. The more powerful the tide, the better.
- Contact: The Nisqually National Wildlife Refuge, 100 Brown Farm Road, Olympia, WA 98506; (360) 753-9467, for information about visiting Grays Harbor National Wildlife Refuge. Staff at the refuge can notify you whether the birds have arrived in the basin. The personnel is also generally aware of the high and low tide timings.
- To get to Grays Harbor National Wildlife Refuge from Aberdeen, use U.S. Highway 101 north via Hoquiam, then Highway 109 toward Ocean Shores. After about a mile, turn left onto Paulson Road and go to the airport. Take the first right onto Airport Way.
- Accommodations: The Grays Harbor Chamber of Commerce, 506 Duffy Street, Aberdeen, WA 98520; (360) 532-1924; www.graysharbor.org, may provide information on local facilities.
WHERE ELSE TO SEE MIGRATING SHOREBIRDS:
Willapa National Wildlife Refuge is located in southern Washington.
Willapa Bay, one of four important shorebird staging regions on the West Coast, is one of the western United States’ biggest unspoiled estuaries. The finest place to see shorebirds is Leadbetter Point near the tip of Long Beach Peninsula.
To get to Leadbetter Point from Aberdeen, use US Highway 101 south to Seaview. Take State Route 103 north. The road ends at Leadbetter Point State Park.
For further information, call the Willapa National Wildlife Refuge at (360) 484-3482 in Ilwaco, WA. Contact the Long Beach Peninsula Visitors’ Bureau, P.O. Box 562, Long Beach, WA 98631; (360) 642-2400, for information on regional facilities.
Dungeness Spit National Wildlife Refuge, northern Washington: This is not a staging place, but many migratory shorebirds, including sandpipers, Dunlins, turnstones, and phalaropes, pause here to rest and eat.
To get to the Refuge from Sequim, go US Highway 101 west for approximately 4 1/2 miles before turning north on Kitchen-Dick Lane. After about 3 kilometres, turn right onto Lotzgesell Road. Access the Refuge through the Dungeness Recreation Area.
For further information, call (360) 457-845l or visit the Washington Coastal Refuges Office at 33 Barr Road S., Port Angeles, WA 98362. The Sequim Chamber of Commerce, P.O. Box 907, Sequim, WA 98382; (360) 683-6197, may provide information about local facilities.
Northwestern Oregon’s Bayocean Peninsula.
High tide is the best time to see spring shorebirds on Bayocean Peninsula, a long, thin sand spit. Keep an eye out in the bay for killer whales.
To get to Bayocean Peninsula from Tillamook, use Netarts Highway west for about a mile to Bayocean Road. Follow the road north for roughly 5 kilometres until you reach the spit road.
Susan Ewing is the author of several books, including The Great Rocky Mountain Nature Factbook and Going Wild In Washington and Oregon, from which “Feathered Bedouins” is excerpted. She writes from her home in Montana.