There are two times of the year the spotlight is on shorebirds here on the Harbor; the greatest concentration of numbers is during the spring migration, but the fall migration brings a better diversity of species…including some of the rock stars of the shorebird world. Among those we find during both times is the Greater Yellowlegs, shown here in a Gregg Thompson photo. This bird is in breeding plumage, well-camouflaged to blend in with the ground on which it nests except for the distinctive long, yellow legs which are tucked beneath its body. Because it nests in mosquito-infested bogs, not as much is known about its breeding habits. It is also the first bird to raise a very loud alarm when disturbed, so trying to study this bird is difficult at any time.
General Description: The Greater Yellowlegs is a sleek, long-necked and long-billed shorebird with long yellow legs. It is approximately 11 to 14 inches tall, with a wingspan of 23 to 24 inches, and weighs 4 to 8 ounces. Breeding plumage is mottled brownish-gray and white with heavy barring all over, a long black bill, and a white tail with barring on the end visible in flight. Non-breeding plumage is less heavily marked, with a pale belly and breast.
Habitat: This bird is most often found in fresh and saltwater wetland habitats, including open marshes, mudflats, estuaries, open beaches, and lakeshores. During breeding season they can be found in muskeg bogs of the northern boreal forest, where small forested islands give safety and shelter to the birds. They are commonly seen on golf courses on rainy days where they are easily spotted against the bright green of the links.
Behavior: Less social than other shorebirds, Greater Yellowlegs may form small groups during migration, but are more often seen as single birds or maybe a pair. They spend a lot of their time feeding while wading, sweeping their bill back and forth in front as they stride through the water. The front half of their body bobs up and down as they forage, and they often run after prey. They are usually the first bird to sound a loud alarm call, causing all nearby birds to flush into the air. Here is a link to their call…it’s distinctive:
https://www.allaboutbirds.org/guide/Greater_Yellowlegs/sounds
Diet: During breeding season, their diet is mostly insects and insect larvae. During winter and migration, small fish, crustaceans, snails, and other aquatic animals round out the diet, with the occasional seeds and berries.
Nesting: Due to its low densities and remote nesting areas, the breeding biology of the Greater Yellowlegs is not well studied, and much is unknown about it. They are thought to be monogamous, with pairs forming after arrival on the breeding grounds. The nest is built in a shallow depression on the ground, next to and concealed by a low bush or hummock. It is lined with grass, leaves, lichen, and twigs. It is thought both parents incubate 4 eggs for 23 days. The young leave the nest within hours after hatching and can find their own food, but stay close to their parents who tend to them until about 23 days of age when they are capable of some flight, or even up until they are strong flyers at 35 to 40 days.
Migration: While some yellowlegs stay the winter here in Washington, most are long-distance migrators. They leave their breeding grounds in late June and make their way to the southern U.S., Mexico, and Central and South America. Their trip north usually begins in late March.
Conservation Status: Throughout their range, Greater Yellowlegs are common and widespread, but their low density, remote breeding grounds, and lack of major stopover or wintering areas make the population difficult to survey. This is also what helps keep them safe from disturbance. Their only major danger is from loss of habitat. Their future may be a bit less sure with the warming climate changing the breeding/hatching patterns of their prey, and with habitat destruction at both ends of their migration journey. If the insects are breeding earlier each year due to earlier warming of the far north, there may be problems with the food chain. For now they are common and abundant.
Where and When to Find on Grays Harbor: Greater Yellowlegs are found year-round out on the coast, but the greatest density of their population can be seen mid-March through mid-May and late June through October. Look for them striding through shallow waters in marshy areas, wetlands, and yes, on golf courses in the rain. Good places to find them are Bottle Beach State Park on SR 105 between Aberdeen and Westport, any sewage treatment pond, and both the John’s River and Oyhut Wilderness Areas. Just look for the long yellow legs.
