Bird of the Week: Canada Warbler

Canada warber by Darlene Friedman
A male Canada warbler rests on a branch in Ohio's Crane Creek State Park. Photo by Darlene Friedman.

Across the United States, tens of thousands of birds that have wintered in Mexico, Latin America and the Caribbean are on the move this month, making their way toward breeding grounds in North America. To celebrate the amazing long-distance feats performed by these birds, as well as raise awareness about the threats migratory species face, communities throughout the continent are sponsoring a variety of activities for International Migratory Bird Day, this Saturday, May 14.

Frequent Fliers

Among the hundreds of species migrating this month, one of the most remarkable is the Canada warbler,  a colorful little insect eater that spends less time on its summer breeding grounds than do most Neotropical migrants—no more than two months total. The birds breed in cool, moist forests across the northeastern United States, boreal Canada and along the central ridge of the Allegheny Mountains as far south as Georgia. They winter  along the western slope of the Andes Mountains, from western Guyana to northwestern Bolivia. The Canada warbler is one of the last warblers to arrive north in spring and one of the first to leave in fall.

Biologists still know very little about the behavior of Canada warblers,  but according to the Cornell Lab of Ornithology, the species appears to be monogamous year-round—somewhat unusual among birds. Pairs of the warblers have been spotted together during both spring and fall as far from their breeding territory as Panama.

Declining Populations

Scientists also know that the Canada warbler has been declining in recent decades. According to the Boreal Songbird Initiative, the species’ numbers in the southern part of its breeding range initially decreased due to forest clearing during the 1700s and 1800s. Beginning in the 1900s, its populations grew to, then surpassed, original levels as farmland was returned to forest.

But data from the North American Breeding Bird Survey show a 3.2 percent annual decline (in the species’ breeding range) since 1980. Forest fragmentation and disturbance are most likely to blame. Meanwhile, Andean forests in the warblers’ winter range also are being lost as are critical stopover sites along the birds’ spring and fall migratory routes.

Voice: Song is an irregular jumble of rich, sweet notes, with an introductory tchip note and syncopated rhythm. Call is a sharp tsik.

Sources: Cornell Lab of Ornithology’s All About Birds, Boreal Songbird Initiative and National Wildlife Federation Field Guide to Birds of North America.

Explore more:
Learn about the threats confronting warblers and other migratory species.
Find out what you can do to help migratory birds in and around your home.
Six top birders share the best places to go birding during spring migration.

May is Garden for Wildlife Month

May is peak migration time for hundreds of species of birds that breed throughout North America. Here at the National Wildlife Federation, it is also when we celebrate Garden for Wildlife Month. During spring and fall migration, birds particularly need food, water and safe places to rest during their long journeys–and you easily can provide these in your own backyard.

Enter Our Photo Contest!

Darlene Friedman took this photo of a Canada warbler in Ohio’s Crane Creek State Park and entered it in the annual National Wildlife photo contest two years ago. Why not enter your best shots this year in the 41st annual National Wildife Photo Contest? Winners in seven categories (including birds) will appear in National Wildlife magazine alongside images taken by some of the world’s top nature photographers.