Lesser Yellowlegs are small shorebirds that can be found along mudflats, sandy beaches, and the edges of ponds and marshes across North America. Identifying Lesser Yellowlegs can be tricky since several shorebird species have yellow legs and a similar body shape and size. However, Lesser Yellowlegs have some unique identifying features and behaviors that can help bird watchers confidently distinguish them from other shorebirds.
Size and Shape
Lesser Yellowlegs are slim, long-legged shorebirds that measure around 9-11 inches in length. They have a thin, needle-like bill that measures about 1-1.5 inches long. Their long legs appear yellow from a distance but are actually a mix of gray, green, and yellow when seen up close. Compared to the very similar Greater Yellowlegs, Lesser Yellowlegs are smaller with a more delicate build and thinner bill. Greater Yellowlegs measure 11-14 inches in length and have legs that appear more solidly yellow from a distance.
Plumage
The plumage of Lesser Yellowlegs provides some key identification clues but can also be confusingly similar to other shorebirds in the Tringa genus. In breeding plumage, Lesser Yellowlegs have subtle gray, brown, and white mottling on their back and wings. Their chest and neck are covered in streaks and spots of gray and brown. They have a white belly. During non-breeding months, their plumage appears more uniformly gray above and white below with a lightly streaked neck and breast.
To distinguish them by plumage alone, focus on the fine streaking on the flanks and neck and very thin, sharp bill. Greater Yellowlegs have bolder streaking below and a proportionally larger and stouter bill compared to their body size.
Behaviors
Lesser Yellowlegs exhibit some behaviors that can aid identification:
- Foraging – They forage by wading in shallow water and mudflats, plunging their bill into the water or mud to catch small fish, crustaceans, and insects. They will sometimes submerge their head completely underwater.
- Flight – Their flight pattern consists of stiff, shallow wingbeats with glides on bowed wings. Their flight appears buoyant compared to other shorebirds.
- Vocalizations – They make a clear, ringing “tu-tu-tu” call while feeding and in flight.
- Habitat – Look for them along inland mudflats, ponds, lakeshores, and saltmarsh edges in migration and winter. In summer they breed in open boreal wetlands and marshes.
- Movement – They frequently bob their tail and rear up in a see-saw motion when wading and foraging.
Range and Seasonality
Paying attention to location and season can also help clue you in to Lesser Yellowlegs sightings:
- Breeding Range – They nest across Canada and Alaska and in the western mountains of the contiguous U.S.
- Migration – They migrate in flocks through interior North America, reaching their wintering grounds by October.
- Winter Range – They winter along the Atlantic and Pacific Coasts from the Southeastern U.S. south to Mexico and parts of South America.
Similar Species
Lesser Yellowlegs share their range with several other small to medium-sized shorebirds with yellow legs. Here is how to distinguish them from similar species:
Greater Yellowlegs
- Larger with a proportionally thicker bill
- Legs appear solid yellow from a distance
- More extensive streaking below
- Slightly larger with a heavier build
Solitary Sandpiper
- Darker legs
- Bold white eye-ring
- Habitat is freshwater streams and ponds
- Distinctive stiff tail pumping motion while walking
Willet
- Thicker gray legs
- Heavier bill
- Black and white striped wing pattern in flight
- Bold black and white stripe on face
Lesser Yellowlegs vs. Similar Shorebirds
| Lesser Yellowlegs | Greater Yellowlegs | Solitary Sandpiper | Willet | |
|---|---|---|---|---|
| Size | 9-11 in | 11-14 in | 7.5-9 in | 15-18 in |
| Legs | Thin, yellow-gray | Thicker, solid yellow | Dark gray legs | Thick gray legs |
| Bill | Thin, needle-like | Long, thicker | Straight, thinner | Thick, slightly upturned |
| Plumage | Finely streaked | Heavily streaked | Plain gray and white | Bold black and white face, stripes on wings |
| Habitat | Mudflats, marshes, ponds | Mudflats, marshes, ponds | Freshwater streams, ponds | Coastal marshes, beaches |
Conclusion
Distinguishing Lesser Yellowlegs from other similar shorebirds takes practice but just remember to focus on size, bill shape, leg color, streaking patterns, behavior, habitat, and vocalizations. The next time you see a small to medium sized shorebird wading in a marsh or along a pond edge, look for those thin legs, a delicate build, and fine streaking to identify it as a Lesser Yellowlegs.
