A Forest For Ducks
November 03, 2010
The boreal forests raises 40-percent of our ducks, and they could be in big trouble
The vibration of the big Pratt and Whitney came up through the jump seat, churned through the scrambled eggs in my stomach, and settled in the fillings of my teeth like a bumblebee in a peanut butter jar. DeHaviland built the Beaver to take off from a patch of water not much bigger than a hot tub, to stay in the air when even a migrating goose is grounded, to fly impossible loads into impenetrable country. It is the quintessential bush plane.
For all that, the designers figured, most backcountry air travelers are willing to make certain sacrifices in comfort. There was no point trying to talk to the rest of the passengers over the roar of the engine, so I put my nose against the window and watched the forest slide by below.
I've spent a fair amount of time flying over wilderness in the Rocky Mountain West, and I've decided I don't like the bird's-eye view. A plane makes big country seem very small. I've looked down on jagged ridges and spruce tangles that took me a week to walk through only to realize that the motor homes and tourist traps were never more than ten or 15 miles away. Wyoming has the most remote wilderness in the Lower 48, and even there, you're never more than 38 miles from a road.
But this was not Wyoming. This was northern Saskatchewan, and the tangle of trees and water below was part of North America's great boreal forest, 2.3-million square miles of timber stretching from the Bering Sea to the rock-bound coast of Newfoundland. The conifers stretched to the horizon in every direction, and the more we flew, the more we saw. The size of the place was beyond imagining.
The processes at work down below operated at a scale worthy of the landscape. As we flew on, I saw the scars of old forest fires, and the sky was hazy and tan with smoke. Out of sight to the west, a fire was in the process of consuming several hundred thousand acres of spruce and jack pine, a cataclysm forestry officials were powerless to stop. The ecological forces in play were invisible from the air, but they were, if anything, even more far-reaching than wildfire, stretching out down the migratory corridors of the New World to touch the tropics and grasslands of Patagonia far to the south.
It's been estimated that 300 species of birds pass the long days of the northern summer in America's boreal forest. Ninety-six of these species depend on this system as a nursery--more than half the breeding populations of these birds nest in the boreal forest. Birds as tiny as the bay-breasted warbler and pine siskin, as imposing as the whooping crane and trumpeter swan, raise their families here.
And it's a great place for ducks. Thirty-percent of the boreal forest is covered with water, bogs, fens, marshes, lakes, and rivers that provide pristine nesting habitat for many species of North American waterfowl. Last summer, 87-percent of our buffleheads nested in the boreal forest.
Eighty-three percent of scaup and common goldeneye, 74-percent of wigeon, 67-percent of green-winged teal, 61-percent of pintails, half of all black ducks summer in the boreal system. When the prairies are dry, a third of the continent's mallards may move north into the conifers to raise their broods. Overall, some 40-percent of our ducks breed in the boreal forest.
That ought to be good news. With a wilderness stronghold to sustain ducks through drought and habitat loss in the prairie potholes, waterfowl and waterfowl hunters should have a buffer even when times are hard. Trouble is that this wilderness stronghold is not as invulnerable as we thought it was a generation ago. As remote as it is, the boreal forest is beginning to feel the effects of human activities.
Name the mineral and the boreal forest has it--diamonds, gold, platinum, uranium, cobalt, iron, copper, lead, zinc. The mines for these commodities don't take up all that much space, but the development that surrounds the mines can have extensive effects on the surrounding forest. Roads, powerlines, toxic wastes in the air and water, a simple demand for water as part of processing can alter habitat.
Development of oil sands on the Athabasca and Peace rivers continues and will probably intensify as the price of oil rises. The oil-bearing sediment is strip-mined and the hydrocarbons in it are "cooked out" with heat, typically in a furnace fired with natural gas. These operations use lots of water, give off large amounts of carbon dioxide, and the pipelines and roads that serve them cut hundreds of miles through the timber.
Farming continues to move north as new crop hybrids and genetically engineered strains are developed to mature faster and resist low temperatures better. As the agricultural technology advances, the southern edge of great forest is steadily giving way to the plow.
It's been estimated that 3,500 square miles of Canadian boreal forest have been flooded for hydroelectric projects. If current plans for new dams are implemented, another 4,000 square miles could be under water by the year 2010. The lakes that result may offer some staging areas for migrating waterfowl, but they are unlikely to provide much nesting or brood-rearing cover.
Of course, hydropower is one of the cleanest sources of energy known. Canada is the top hydropower producer in the world and sells significant quantities of electricity to the United States, so the impacts of new hydro projects in the boreal forest have to be balanced against the potential damage that increasing carbon dioxide and climate change may have. More on that in a moment.
In a 2006 technical paper, Eric Kasischke and Merritt Turetsky reported that the amount of boreal forest that burns in an average year has doubled since 1959. At the same time, the number of fires started by people has declined.
"This likely has occurred because drier conditions have increasingly allowed fires to grow faster and/or burn over a longer time period," they conclude.
A drier forest means less habitat for waterfowl, and it also makes it easier to build roads, which accelerates development.
Drier, warmer weather also gives an edge to native insects that attack boreal timber. CBC reports that as much as 8,000 square miles of pine forest on Alberta is at risk of attack from the mountain pine beetle, a native tree parasite whose populations have exploded across the Rockies in the last four years as a result of unusually warm, dry winters in the region.
Insect outbreaks and increasingly severe forest fires may well be symptoms of a more serious threat to the future of the boreal forest--climate change. Scientists with the Intergovernmental Panel on Climate Change expect that temperatures in Alaska and central Canada will see "much greater than average warming" over the next century. Temperatures in the boreal region have already increased by three to four degrees Fahrenheit, and some models estimate that the temperature may ris
e as much as 18 degrees Fahrenheit in the next century.
Even if precipitation increases, the overall effect of this warming will be to make the landscape drier and move the edge of the forest north.
It's hard to say whether this suite of problems has already begun to take effect. On one hand, the boreal forest is vast-- the losses in area are miniscule in comparison. On the other hand, the populations of at least forty of the bird species that use the forest have declined over the last 60 years.
The trouble is distributed across sizes and habits. The bay-breasted and blackpoll warblers have shown troubling declines, probably due to spraying for spruce budworms. The white-crowned sparrow, a common and widespread boreal forest nester, has seen steady declines. The solitary sandpiper is particularly difficult to monitor, but available information suggests a decline in numbers. The rusty blackbird's population is in freefall.
And several ducks that favor the boreal forest have also shown signs of difficulty. The greater and lesser scaup have struggled in the last 30 years; so have the pintail, black duck, and white-winged scoter. At the same time, the American wigeon and green-winged teal have generally prospered in the north country. These mixed trends may be accident, or they may suggest a range of ecological effects we don't yet understand.
Just once, it would be nice to get ahead of a major challenge in waterfowl conservation. We have that chance with the boreal forest. The Canadian government has launched a collaborative program it calls the Western Boreal Conservation Initiative, which may at least provide a forum for discussing land uses in the boreal forest.
But the key issue is beyond the reach of any single government. Climate change is beginning to change the world. We can try to dodge it, deny it, excuse it, but if we don't get on our way toward a solution, a decline in boreal forest ducks may be the least of our problems.