Commentary: There’s plenty to eat at the beach

Our Gulf Coast hosts numerous species of shorebirds in winter, accommodating a diverse range of appetites and foraging styles. The tides, surf and sand serve enough bounty to go around. By spring, many of the visitors have returned to their breeding grounds but some of the more entertaining birds remain into the summer.

Shorebird is a designation for a large group of 217 recognized species of birds that can be found on the world’s beaches at any time of the year and especially during winter. Most shorebirds are migratory.

One of the most widespread of all shorebirds is the sanderling, a medium sized sandpiper about eight inches in length that can be found on our local beaches nearly year-round. Like gleeful squealing children chasing and being chased by the surf, sanderlings are those small white and gray birds that run up and down the beach, chasing receding waves and quickly changing direction to scurry in front of an incoming tide.

Unlike playful children, sanderlings are feeding, looking for stranded invertebrates and probing the wet sands for prey as the tide goes out. Their varied diet includes small crabs, shrimp-like amphipods and other small crustaceans and mollusks that they grab up, invisible to us beachcombers. Sanderlings also eat horseshoe crab eggs and polychaete worms, a segmented marine worm found at all depths of the oceans.

Because of their diet and food searching habits, sanderlings often consume difficult to digest exoskeletons, shell fragments and sand and often regurgitate pellets of those indigestible parts onto the beach.

Come spring, most sanderlings migrate back to their breeding grounds to the far north High Arctic tundra. Nonbreeding first year sanderlings may stay all year at their winter site. During the summer, they snatch flying insects from the air, such as crane flies, midges, mosquitoes, beetles, butterflies and moths.

Beach companions to sanderlings are often small flocks of ruddy turnstones, a somewhat larger bird, 9 to 10 inches in length. Their beach habits and diet differ enough, so there is plenty to keep both species sated.

Ruddy Turnstones also are sandpipers, and they rival the sanderling’s worldwide distribution. They, too, nest on high arctic tundra of North America and Eurasia and winter along the coastlines of six continents, including the Gulf of Mexico.

A colorful shorebird, ruddy turnstones have vivid rust, black and white, nearly harlequin-patterned back and wings, a black face stripe on a white face, and orange legs.

While looking for food, ruddy turnstones use their bill to flip over shells, pebbles and other debris washed onto the beach. They frequent the drift line on beaches and also join sanderlings near the surf. Ruddy turnstones dig holes in the sand, sometimes as large as the bird itself, searching for small crabs. Barnacles, insects, spiders, beetles, bees, and wasps are diet fare as well. They will pick at dead fish and mammals that wash up on shore.

Both species especially like to poke and probe through freshly washed-up seaweed, hunting for little crustaceans and other small invertebrates.

Anita Westervelt is a Texas Master Naturalist.