The Bountiful Boreal

Few places on the planet are as crucial to wildlife as North America's boreal forest, where up to 3 billion birds breed every year; but can the vast, increasingly beseiged sanctuary survive

  • Paul Tolmé
  • Oct 01, 2004

EVERY SPRING, the aspen and poplar along the shores of Lesser Slave Lake in Alberta explode with color and sound as North America's migratory songbirds return to the continent's vast northern forest. First come the American robins, which flash their orange chests amid lingering April snows. Waves of yellow-rumped, Tennessee and Connecticut warblers follow and add to the frenzy. Canada warblers, having flown thousands of miles from as far away as Brazil, feast on caterpillars and insects in the budding branches. Olive-sided flycatchers and northern orioles join the treetop parade, followed by hummingbirds, woodpeckers, swallows, vireos and tanagers. The sheer volume of birds astounds visitors. "Sometimes you look up," says Frank Fraser, director of the Lesser Slave Lake Bird Observatory, "and there are thousands of songbirds in the sky. It's a feast for the eyes and ears."

Located along a major migratory bird flyway, the food-rich lakeshore is a gateway to one of Earth's last great avian breeding grounds: North America's immense boreal forest. Along with the Amazon rain forest and Siberian taiga, the boreal ranks among the largest remaining forests on the planet. (Its name comes from Boreas, the Greek god of the North.) Extending across the top of the continent from interior Alaska to Newfoundland, and from Arctic tundra to temperate forests and grasslands hundreds of miles south, the boreal's 1.4 billion acres—more than 90 percent of them in Canada—are big enough to hold 14 Californias.

STRETCHING across the top of North America, the boreal's 1.4 billion acres—90 percent of them in Canada—could house 14 Californias.

REMARKABLY faithful, both to their partners and breeding habitat, common loons mate for life and have been observed returning to the very same boreal lake to raise chicks each summer for as long as 20 years.

The boreal is a global treasure for bird lovers. The forest is home to at least 298 bird species, from bald eagles to loons and woodpeckers. Forty of these species, including black-backed woodpeckers, northern shrikes and white-throated sparrows, have more than half their global populations in the forest. A quarter of the world's populations of many other birds—including broad-winged hawks, ruffed and spruce grouse, black-billed cuckoos, great gray owls, belted kingfishers and northern flickers—also are found in the boreal. Four out of every 10 North American waterfowl species breed in the region's bogs and wetlands. Even American white pelicans, which winter in Mexico and Florida, breed and summer on lakes in Alberta, Saskatchewan and Manitoba.

WHITE-THROATED SPARROWRelying almost exclusively on the continent's boreal forest to breed, more than 100 million of these beloved backyard songsters nest in the region each year. But studies show that the species' numbers are declining by nearly 1 percent annually across its range.

What makes the boreal truly special, however, are the tiny songbirds so beloved by backyard birders. Up to a billion sparrows and 2 billion warblers hatch annually in the region's pine, spruce, larch, aspen and poplar. The forest provides breeding grounds to more than 80 percent of all Philadelphia vireos and palm, Tennessee, Connecticut and Cape May warblers. Dark-eyed juncos and white-throated sparrows, two of the most abundant fall and winter backyard birds in the United States, also breed in the boreal. Tennessee warblers are named after the U.S. state, yet 97 percent of these green and yellow birds hatch in the forest, along with 92 percent of Connecticut warblers. "The boreal is a mecca for all the colorful warblers and songbirds American birders enjoy on a regular basis," says Peter Blancher, a researcher with Bird Studies Canada and author of the report Importance of Canada's Boreal Forest to Landbirds.

But this songbird mecca is in jeopardy. The roar of chainsaws and the oily grind of bulldozers are beginning to drown out the birdsong. The boreal holds vast reserves of natural gas and timber. To extract these commodities, large areas of the forest are being divided and fragmented by pipelines and service roads. Timber companies have been harvesting roughly 2.5 million acres a year, and about half the forest area suitable for cutting has been licensed to logging companies for future harvests.

Sadly, U.S. consumers—even those who most enjoy boreal-breeding birds—are largely responsible: A majority of the oil and gas extracted from the boreal goes to the United States. Canada, not Saudi Arabia, is the United States' largest supplier of fossil fuels, leading some environmentalists to call the country "America's gas tank." Likewise, most of the wood products exported from Canada—about 80 percent—go to the United States.

LOGS IN ONTARIO represent a tiny fraction of the 2.5 million acres of boreal forest cut each year; two-thirds of the wood is pulped for paper.

BOREAL DENIZENS that rely on the forest for at least part of the year include (clockwise from left): the American robin, peregrine falcon, caribou, dark-eyed junco, American white pelican and spruce grouse. Many seasonal inhabitants—including robins and juncos—are common backyard birds in the United States during fall, winter and spring. But by summer, most have returned to the boreal's pine, spruce, larch, aspen and poplar to breed and raise their chicks.

Even more troubling, about two-thirds of the wood cut in the boreal is pulped for paper used primarily to produce newspapers, promotional mailings and catalogs. (NWF's publications are not printed on this paper.) Seventeen billion catalogs alone—59 for every U.S. citizen—are mailed annually in the country, according to the San Francisco-based conservation organization ForestEthics. Most of these catalogs are made of virgin fiber, and most go straight into the garbage. While Canada's forests shrink, U.S. landfills overflow. "This senseless consumption is destroying one of the last great forests on the planet," says Lafcadio Cortesi, boreal program director for ForestEthics. "This is truly shameful."

At a time when forest habitat is also disappearing from the United States to South America, migratory birds that breed in the boreal are paying the price for this increased industrialization. The rusty blackbird—70 percent of whose population relies on the boreal—has declined nearly 11 percent a year across North America. Connecticut, mourning, Canada and blackpoll warblers are also declining, according to Blancher's study. Other birds dropping in numbers include the least flycatcher, Swainson's thrush, white-throated sparrow, dark-eyed junco and purple finch.

Up to 60 million blackpoll warblers—65 percent of the species' global population—nest in the boreal each summer. Wintering as far south as the Amazon, the species has the longest migration of any North American songbird. The bird's populations are declining nearly 4 percent a year.

In the face of such losses, conservation-minded Canadians have launched some innovative efforts to save the boreal. Last winter, for example, 11 environmental organizations, indigenous groups and timber and oil companies developed a vision for preserving the ecological and cultural integrity of the region. Outlined in the Boreal Forest Conservation Framework, it includes establishing large protected areas in at least half the region, with environmentally responsible standards for development in the other half. "Without a doubt, the boreal is one of the greatest forest conservation opportunities left on Earth," says Marilyn Heiman of the Boreal Songbird Initiative.

But as of last July, Canadian governments had not yet implemented some key parts of the framework, including planning for conservation before new developments are approved. Support from U.S. conservationists, politicians and consumers is crucial, says Heiman. "Americans have a responsibility to be part of the solution, given that we directly contribute to problems in the boreal."

IN BREEDING plumage, a male yellow warbler perches on a branch in northern Ontario. About a quarter of the global population of yellow warblers breeds in the boreal each summer.

LIKE A REFRIGERATOR, the boreal's cold temperature impedes decomposition, preventing the release of climate-changing carbon dioxide.

Heiman says U.S. birders can help by writing to catalog and other companies asking them to purchase paper only from ecologically and socially responsible sources. Birders can also assist by volunteering time to research projects such as the Atlas of Breeding Birds of Alberta. Such "citizen science" is crucial because the boreal is simply too vast for experts alone to study, says George Newton of the Federation of Alberta Naturalists. Alberta, for instance, is the size of Texas, and as Blancher points out, "only the southern edge of the boreal here has been studied."


Of all the reasons to preserve the boreal forest, its role in regulating Earth's climate may provide the strongest cause for action.

This immense northern woodland serves as a repository for vast quantities of carbon, which is stored in a layer of plant material on the forest floor that in some areas is more than 10 feet thick. (Just one centimeter can hold two-and-a-half tons of carbon per acre.) The organic matter piles up because the cold boreal forest, like a giant refrigerator, prevents fallen trees, leaves, needles and other plant remains from decomposing, a process that releases carbon dioxide (CO2), the most important greenhouse gas thought to be changing global climate.

Together, the boreal forests of Canada and Russia (also called the taiga) store more carbon than any other terrestrial ecosystem on the planet. But "the carbon stored in the soils is very vulnerable," warns boreal researcher and University of Maryland geographer Eric Kasischke. When the forest's trees are cut, its thick layer of organic matter heats up and decomposes rapidly, potentially releasing large plumes of CO2 into the atmosphere.

Higher temperatures caused by global warming already are heating up the boreal region. Indeed, the northern forests of Canada and Russia are warming faster than nearly any place on the planet. The big question is whether the boreal has transformed from a "sink," which takes in more carbon than it releases, to a "source" of carbon. "The consensus seems to be that the boreal is moving toward being a source," says Terry Chapin, a University of Alaska–Fairbanks ecology professor. If that's true, the loss of carbon from the boreal could lead to greater warming, which in turn would release more carbon, causing even more warming.

Increased temperatures are also causing more wildfires. Since the 1960s, the acreage burned in North America's boreal has doubled to 7.6 million acres annually. In Russia's boreal, which is even larger than North America's, a whopping 25 million acres are burning annually, although poor records from the Soviet era make it difficult to ascertain whether this is actually an increase.

One reason boreal fires are growing larger is that there are more infestations by bark beetles than there once were. Warmer temperatures are allowing the beetles to proliferate and kill more trees, which become standing tinder. "The more death and destruction you have in these forests, the more fires you will have and the more carbon you will see released into the atmosphere," says Benjamin Preston, senior research fellow at the Pew Center on Global Climate Change.

Over time, if nothing changes, global warming will transform the boreal: Grasslands will claim its southern edge, and the forest's vast wetlands—a third of Canada's boreal is covered in bogs, fens, marshes and an estimated 1.5 million lakes—will shrink. In preparation, the Canadian Forest Service has begun collecting seeds of spruce, pine and other boreal species to plant if the trees are decimated.

University of Alberta freshwater ecologist David Schindler says the decline of this forest, which took 65 million years to evolve, is an epic tragedy. This avid outdoorsman recalls the days before natural gas pipelines and clear-cuts marred the boreal, when he could canoe and hike for days without seeing another human. "I can only hope," says Schindler, "that we see the light and change our ways before the boreal is gone forever."—Paul Tolmé

Only now are ornithologists beginning to answer basic questions about crucial boreal species. Take the yellow-bellied sapsucker, believed to be a keystone species whose fate affects large numbers of others. This bird pecks holes in birches and aspens and feeds on the sap, which draws insects that in turn feed other birds. During cold springs, hummingbirds, for example, survive thanks to the work of sapsuckers. Despite the importance of the birds, researchers are "clueless" about the distribution and numbers of sapsuckers, says Richard Thomas, a private environmental consultant who has studied deforestation in Canada. "It is my firm belief," says Thomas, "that birders should tithe a percentage of their time to bird conservation and research so we can answer some of these questions."

THE BELTED kingfisher, a quarter of whose global population breeds in the boreal forest, is one of just 11 kingfisher species worldwide that migrates, and is the only North American species that makes seasonal journeys.

Scientists, meanwhile, are racing to understand the effects of industrialization on birds. "There is no doubt we are changing the forest," says conservation biologist Fiona Schmie-gelow of the University of Alberta. But "how are these impacts changing the quality of the habitat? That's what we must find out." Another significant unknown is the extent to which timber harvesting in the boreal will contribute to global warming (see previous page).

At Lesser Slave Lake, Fraser directs a bird-banding program aimed at unraveling some of the boreal's mysteries. Researchers catch songbirds in large nets, place bands on their legs and release them. Fluctuations in bird numbers from season to season are cataloged, but it will take many more years of research before scientists understand the breeding behavior of many songbird species. "We are trying to determine where all these species go once they leave here," he says.


NWF prints all of its magazines, catalogs and promotional mailings on paper that is either recycled or made from pulp originating in sustainable, certified forests. Taking a more active role to safeguard the boreal, NWF participates in the Boreal Songbird Network, a partnership of environmental groups working to build international support for protecting the forest, including adoption of the Boreal Forest Conservation Framework. In addition, NWF urges its members to contact catalog retail companies that use paper harvested in the boreal, asking these companies to change their purchasing strategies. To learn more, see

One thing is certain: Come late summer, newly hatched songbirds and their parents, fattened up on boreal bugs and fruit, will point their beaks southward and commence the fall migration. Cooper's and sharp-shinned hawks, peregrine falcons and other raptors will follow in hot pursuit. The fall migration is even larger than in spring because of the volume of juvenile birds. By some estimates, up to 5 billion birds wing their way into the United States and further south from late summer into September. First to arrive each spring, American robins are also the last to leave Lesser Slave Lake. By October, ice and snow once again blanket the land, and winter's quiet descends on North America's greatest bird breeding grounds.


While much of the boreal's extraordinary bird life occurs far off the beaten path, there are many accessible Canadian parks and reserves where the forest's abundant avian fauna—both year-round residents and migrants—can be easily observed. Here are four of the best:

• Terra Nova National Park, Newfoundland. Where: 155 miles north of the capital city of St. John's. When to go: June or early July. What to look for: boreal chickadees, gray jays, spruce grouse, pine grosbeaks, black-backed woodpeckers, ruby-crowned kinglets, blackpoll warblers, plus 20 other warbler species during the breeding season.

• Whiteshell and Nopiming Provincial Parks, Manitoba. Where: on the edge of the Canadian Shield along the Ontario border in southeastern Manitoba. When to go: March through June or winter (for owls). What to look for: yellow-bellied flycatchers, Connecticut and black-throated blue warblers, Le Conte's sparrows, yellow rails, sharp-tailed and spruce grouse, wood thrushes, scarlet tanagers and boreal owls.

• Prince Albert National Park, Saskatchewan. Where: 125 miles north of Saskatoon near the town of Prince Albert. When to go: mid-May (for migrants) through the first two weeks of June. What to look for: blue-headed vireos; blackburnian, black-throated green, Cape May and magnolia warblers; boreal chickadees; gray jays; western tanagers (right) and all boreal woodpecker species.

• Lesser Slave Lake Bird Observatory, Lesser Slave Lake Provincial Park, Alberta. Where: 155 miles north of Edmonton. When to go: May through mid-August. What to look for: American redstarts, white-throated sparrows, least and alder flycatchers and yellow-rumped warblers (the observatory's five most frequently encountered banded species), plus numerous other songbirds during spring migration. —Neil Osborne

Colorado journalist Paul Tolmé wrote about climate change and wildfires in the August/September 2004 issue.

Get Involved

Where We Work

More than one-third of U.S. fish and wildlife species are at risk of extinction in the coming decades. We're on the ground in seven regions across the country, collaborating with 52 state and territory affiliates to reverse the crisis and ensure wildlife thrive.

Learn More
Regional Centers and Affiliates