You’ve seen them on the beach. Those little speckled gray, black, and white birds scurrying up and down the wet sand playing wave tag on the water’s edge. The wave goes out and they run down, the wave comes in they run back. Every time the wave recedes, they spend that brief moment furiously jabbing their beaks into the sand hoping to catch some critter like a sand crab, worm, or crustacean before the next wave chases them back up the beach. When you see a tight knot of these little black-legged birds doing this obsessive wave-chasing behavior you can be certain you’re seeing Sanderlings.
Sanderlings belong to a group of birds many people call “peeps”. Not the bright yellow marshmallow goodies that show up every year around Easter; but rather a term used for the several small sandpipers we can find along our beaches and bays. Least sandpipers, Western Sandpipers, Semi-palmated Sandpipers, and Sanderlings are some of the more commonly seen peeps around these parts, but we won’t see many of them at the beginning of summer. That’s when these little powerhouses are up in the Arctic nesting.
The high Arctic summer is short but productive. Once the snow is gone, animals from birds to insects make the most of the long days of sunlight, feeding and reproducing in great numbers. Most peeps will find low scrubby tundra areas, usually by water, to create their nests on the ground. Their little speckled eggs are placed in a non-descript depression where the birds take turns incubating them. Things happen fast up there with their young hatching out in a few weeks and able to walk soon after emerging.
The little balls of fluff on thin stick legs follow their parents searching for the innumerable invertebrates and their larvae to feed on. If predators come by, the young will freeze at the sound of their parents’ alarm call. Lying prostrate, the young rely on their camouflage coloring to hide them. If the predator gets too close the parents will try to lure it away with plaintive calls while feigning injury.
Within three weeks the chicks will be fully feathered and ready to follow their parents and other members of their species south towards their winter haunts. By late July or early August, the peep migration is in full swing with flocks of these little birds winging their way south to places like Morro Bay or as far as Brazil. There they spend their days on marshes and beaches feeding, resting, and trying to avoid becoming a meal for a falcon like a Merlin or Peregrine.
Peeps use the safety-in-numbers strategy. The same strategy is used by herds of mammals, other flocks of birds, swarms of insects, and schools of fish. If you ever see a tight bunch of little birds over the water or marsh twisting this way and that, their bicolored bodies flashing in the sun, chances are they are being pursued by one of those avian predators.
These little birds like sanderlings and sandpipers will travel hundreds or thousands of miles to spend time on our shores, sometimes for months. Other times they’ll just stop for a day or so to rest, and tank up on nutrients, before the next leg of their journey along the Pacific Flyway. Peeps may be little, but impressive things can come in small packages.