Tringa melanoleuca-under construction

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A Greater Yellowlegs looking for food in a Florida salt marsh. Photo credit: Antonio Silveira

Tringa melanoleuca - Greater Yellowlegs

Habitat For breeding, the Greater Yellowlegs can be found in the boreal zone in wet bogs with small islands and in coniferous forests that have several clearings. They can also be found in wet areas covered with lots of mosses. A usual breeding area are small ponds and lakes. The Greater Yellowlegs have also been known to use subarctic tundra and subalpine scrub as breeding sites.

In the winter, they can be found in wetland habitats that can be freshwater or saline. If the feeding range is tidal dependent, they will roost on offshore rocks and reefs.

Range Greater Yellowlegs breeds throughout a narrow range in central Canada, Newfoundland and eastern Nova Scotia to eastern British Columbia. The breeding range also extends into Alaska, along the southern Pacific coast. They winter along the ocean coasts of North America from New York through the the Gulf of Mexico and from California south to Central America.

Description Greater Yellowlegs are medium size shorebird with distinctive long, bright yellow legs. It has a common length of 36cm. Its white tail is crossed with thin, black bars, adding to its cryptic coloration. It has a long, thin, slightly upturned, dark bill with a paler base. The bill length is about 1.5 times the length of the head. Males and females look alike and the juveniles have plumage like the matures.

During the winter, adults have pale heads and necks with little brown streaks on them. The breast and flanks are spotted and streaked grayish-brown. They also have a dark brown back with lighter featheredges.

Lastly, this species is often confused with its cousin the Lesser Yellowlegs. The most distinguishing difference between the two species is their size.

Ecological Notes Greater Yellowlegs mainly eat small aquatic and terrestrial invertebrates. They also feed on small fish, frogs, seeds and berries. Sometimes, they are observed eating insects along shores and even snatching them out of the air.

Personal Information Once considered an important game bird due to its challenge to catch, it was hunted excessively. Their population numbers were declining until the Migratory Bird Treaty Act was singed into law in 1918. Since the late 1920s, the bird has been fully protected in the U.S. and Canada. It is assumed that population numbers have increased but this has yet to be confirmed. DDE (a breakdown product of DDT) and PCBs have been studied in this species. Surprisingly, these chemicals have not adversely affected this species. The heavy metal selenium has been found in these birds. This can be a concern because it could decrease survival rates because of high toxicity. Selenium can cause developmental problems Currently, the biggest threat to these birds is habitat loss.

References

Animal Diversity Web
Cornell Lab of Ornithology
National Audubon Society


Additional Information

Before you explore the following publication, the Greater Yellowlegs is not a highly studied species. Not much is known about them and research on them specifically is limited.

Ikuta, Laurie, and Daniel Blumstein. "Do fences protect birds from human disturbance?." ScienceDirect. N.p., 7 Aug. 2003. Web. 25 Apr. 2014. <http://www.sciencedirect.com/science/article/pii/S0006320702003245>.

This publication looks at ecotourism and the conservation of avian species on protected, fenced in land and protected, opened land. They found birds on the protected sites that were fenced in responded similarly to birds at the low visitation (limited tourism) fenceless sites. Behavior at the high tourism sites was much different. In the end, they suggest that by reducing tourism traffic and providing areas of refuge within highly visited habitats is the best solution so birds can behave as they would in an undisturbed habitat.

Keywords: Conservation behavior; Human impacts; Fencing; Buffer distances

LONG, LINDA, and JOHN RALPH. "DYNAMICS OF HABITAT USE BY SHOREBIRDS IN ESTUARINE AND AGRICULTURAL HABITATS IN NORTHWESTERN CALIFORNIA." BioOne Online Journals . N.p., 11 June 2001. Web. 25 Apr. 2014. <http://www.bioone.org/doi/abs/10.1676/0043-5643(2001)113%5B0041:DOHUBS%5D2.0.CO

The authors examined the forgiving behaviors of birds that use estuarine and agriculture habitats in an area in California. They observed who used the lands regularly and seasonally. They then concluded that use of land by the species was dependent on the season and the characteristics of the land. Greater Yellowlegs were documented as seasonal users and were spotted in the estuarine habitats most of the time.


Contributed by Christopher Bierman - Spring 2014

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