Blackpoll Warbler
Encyclopedia
The Blackpoll Warbler, Dendroica striata , is a New World warbler
. Breeding males are mostly black and white. They have a prominent black cap, white cheeks and white wing bars. The Blackpoll breeds in northern North America
, from Alaska
, through most of Canada
, and into the Great Lakes region and New England
.
They are migratory
, wintering in northwestern South America
. They are rare vagrants to western Europe
, although their northerly range and long-distance migration make them one of the more frequent transatlantic passerine
wanderers.
Non-breeding birds of this species have greenish heads, dark-streaked greenish upperparts and yellowish breasts, with the yellow extending to the belly in young birds. Their wing bars are always present.
trees grow. These birds' breeding ranges extends to the taiga
. Blackpoll Warblers commonly nest in a relatively low site which can be found in a conifer, and they lay 4-9 eggs in a cup-shaped nest.
Baird describes the Fall migration of the Blackpoll. From their breeding grounds across the northern latitudes, they converge on the Northeastern United States south to Virginia starting in mid-August. As they forage in the staging area, the birds will often double their weight in fat. Then they fly southward over the Atlantic burning, according to Baird, .08 grams of fat every hour. They travel about 27 miles per hour. Their oceanic flight covers over 2000 miles and takes about 80 hours. Blackpolls weigh up to 20 grams when the leave the United States and lose 4 or more grams by the time they reach South America. Some of the Blackpolls land in Bermuda before going on. Some birds, often with lower body weights, don't make it.
Island stopovers at Bermuda and other places have been cited as evidence of migratory pathways. Baird's conclusion, stated above, differed from Cooke (1904, 1915) and Murray (1965, 1989). Cooke and Murray contended that the Blackpoll Warbler migrates to South America along the mainland of southeastern North America. Baird, Nisbet and others argued that most Blackpoll Warblers fly directly from northeastern North America over the Atlantic Ocean to their winter range. They used data from nocturnal accidents, banding stations and sightings to state that Blackpoll Warblers are rare autumn migrants south of Cape Hatteras, North Carolina, whereas north of Hatteras they are common. Those holding to a direct oceanic pathway pointed to this evidence to support their hypothesis.
New World warbler
The New World warblers or wood-warblers are a group of small, often colorful, passerine birds restricted to the New World. They are not related to the Old World warblers or the Australian warblers....
. Breeding males are mostly black and white. They have a prominent black cap, white cheeks and white wing bars. The Blackpoll breeds in northern North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, from Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
, through most of Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, and into the Great Lakes region and New England
New England
New England is a region in the northeastern corner of the United States consisting of the six states of Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and Connecticut...
.
They are migratory
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
, wintering in northwestern South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
. They are rare vagrants to western Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, although their northerly range and long-distance migration make them one of the more frequent transatlantic passerine
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
wanderers.
Description
The Blackpoll Warbler measures 4 inches in length and weighs about 10 grams, the weight of a ball point pen. The summer male Blackpoll Warblers have dark-streaked brown backs, white faces and black crowns. Their underparts are white with black streaks, and they display two white wing bars. The adult females essentially resemble washed-out versions of the summer males, and in particular, the females lack the strong head patterns, and their crowns and faces are shades of gray.Non-breeding birds of this species have greenish heads, dark-streaked greenish upperparts and yellowish breasts, with the yellow extending to the belly in young birds. Their wing bars are always present.
Habitat
In the southern portion of their breeding range, Blackpoll Warblers can be found on the higher elevations of mountains. They also spend their summers on the wooded coastal islands of Maine and the Maritime Provinces. Father North they have been reported throughout the boreal coniferous forest. Blackpolls breed nearer to the tundra than any other warbler.Diet
They birds are insectivorous, but will opt for berries in winter. They often forage high in trees, and sometimes catch insects while in flight.Reproduction
Their breeding habitats are coniferous woodlands, especially those in which spruceSpruce
A spruce is a tree of the genus Picea , a genus of about 35 species of coniferous evergreen trees in the Family Pinaceae, found in the northern temperate and boreal regions of the earth. Spruces are large trees, from tall when mature, and can be distinguished by their whorled branches and conical...
trees grow. These birds' breeding ranges extends to the taiga
Taiga
Taiga , also known as the boreal forest, is a biome characterized by coniferous forests.Taiga is the world's largest terrestrial biome. In North America it covers most of inland Canada and Alaska as well as parts of the extreme northern continental United States and is known as the Northwoods...
. Blackpoll Warblers commonly nest in a relatively low site which can be found in a conifer, and they lay 4-9 eggs in a cup-shaped nest.
Migration
The Blackpoll is the latest of the spring warblers to come north.Baird describes the Fall migration of the Blackpoll. From their breeding grounds across the northern latitudes, they converge on the Northeastern United States south to Virginia starting in mid-August. As they forage in the staging area, the birds will often double their weight in fat. Then they fly southward over the Atlantic burning, according to Baird, .08 grams of fat every hour. They travel about 27 miles per hour. Their oceanic flight covers over 2000 miles and takes about 80 hours. Blackpolls weigh up to 20 grams when the leave the United States and lose 4 or more grams by the time they reach South America. Some of the Blackpolls land in Bermuda before going on. Some birds, often with lower body weights, don't make it.
Scientific Studies and Discussion
The Blackpoll Warbler's transoceanic flight has been the subject of over twenty-five scientific studies. Sources of data include radar observations, bird banding and weights taken, dead birds recovered from field sites and fatal obstacles.Island stopovers at Bermuda and other places have been cited as evidence of migratory pathways. Baird's conclusion, stated above, differed from Cooke (1904, 1915) and Murray (1965, 1989). Cooke and Murray contended that the Blackpoll Warbler migrates to South America along the mainland of southeastern North America. Baird, Nisbet and others argued that most Blackpoll Warblers fly directly from northeastern North America over the Atlantic Ocean to their winter range. They used data from nocturnal accidents, banding stations and sightings to state that Blackpoll Warblers are rare autumn migrants south of Cape Hatteras, North Carolina, whereas north of Hatteras they are common. Those holding to a direct oceanic pathway pointed to this evidence to support their hypothesis.
Sources Cited
Database entry includes justification for why this species is of least concern- New World Warblers by Curson, Quinn and Beadle, ISBN 0-7136-3932-6
- Blackpoll Warbler. The Cornell Lab of Ornithology: All About Birds. Access: May 20, 2011
- http://books.google.ca/books?id=KP3JlIvW88QC&pg=PA65&dq=%22blackpoll+warbler%22&hl=en&ei=Wt7WTZPsNMOWtwe8zdyIBw&sa=X&oi=book_result&ct=result&resnum=2&ved=0CDUQ6AEwAQ#v=onepage&q=%22blackpoll%20warbler%22&f=falseBaird, James. (1999) Returning to the Tropics: The Epic Autumn Flight of the Blackpoll Warbler in Kenneth P. Able's Gathering of Angels. Ithaca, New York: Cornell University Press, pages 63-78.]
External links
- Blackpoll Warbler Information and Photos - South Dakota Birds and Birding
- Blackpoll Warbler Species Account - Cornell Lab of Ornithology
- Blackpoll Warbler - Dendroica striata - USGS Patuxent Bird Identification InfoCenter
- Stamps for: GrenadaGrenadaGrenada is an island country and Commonwealth Realm consisting of the island of Grenada and six smaller islands at the southern end of the Grenadines in the southeastern Caribbean Sea...
, GuyanaGuyanaGuyana , officially the Co-operative Republic of Guyana, previously the colony of British Guiana, is a sovereign state on the northern coast of South America that is culturally part of the Anglophone Caribbean. Guyana was a former colony of the Dutch and of the British... - Blackpoll Warbler videos on the Internet Bird Collection
- Blackpoll Warbler photo gallery VIREO