Global warming affects everything – there are no isolated instances. From increased frequency and intensity of forest fires in the northwest, to beach and dune erosion along the Great Lakes’ shorelines, to flooding around the Thousand Islands, every corner of the province could be profoundly altered by climate change. How will our wildlife feel the impact of rising temperatures? Some, like the snow goose, seem to be benefitting from a greater range of habitat, while others, such as wood frogs, could be frozen out. Here are some highlights of what’s to come.
By Allan Britnell
Black and white spruce are much more than iconic conifers; as well as being prized for their timber, spruce forests provide winter shelter for caribou and moose and their seeds sustain a diverse group of birds and small mammals. These trees also attract an eponymous pest, the spruce budworm, a moth whose larvae feeds on their shoots. While the population of this native moth ebbs and flows over a 30- to 40-year cycle, recent outbreaks have been defoliating large swaths of forest north of Lake Nipissing and along the St. Lawrence River, two areas where the insect had not previously been a significant problem. The spread cannot be attributed conclusively to climate change, but it is suspected of being a leading cause, and Canadian Forest Service researchers predict that climate change will lead to “prolonged, severe outbreaks of spruce budworm.”
Warmer boreal temperatures are also projected to increase the range of fast-growing species such as birch and aspen, as well as a number of invasive species, all of which could crowd out spruce saplings.
The sugar maple could one day be more commonly found on our flag than in the wild. A 2005 World Wildlife Fund report on the implications of a global temperature increase of 2 C by the middle of this century concluded that, according to various models, sugar maples were one of several “commercially valuable species [that] showed consistent declines.” (Others include black spruce and Jack pine.)
Such a drop would not only be bad news for the forestry industry, but could also have negative effects on a number of creatures that inhabit sugar maple forests. The trees’ seeds, leaves and bark are food sources for squirrels, porcupines, deer and countless insects; the trunk and leafy canopy provides nesting sites for black-capped chickadees, pileated woodpeckers and screech owls. The deep roots of the sugar maple draw water up close to the surface of the ground and then release it into the surrounding soil at night, where it can be taken up by shallow-rooted understorey plants.
We humans would also suffer: if freezing cold nights do not follow warm days in early spring, the trees cannot produce the sap required to make maple syrup.
Pelee Island’s latitude – south of the 42nd parallel, the island is at the same level as California’s northern border – and the moderating effects of Lake Erie combine to give the 47-square-kilometre land mass one of the mildest climates in the country, making it a suitable home for the endangered eastern prickly pear cactus. The flat, green, spike-covered oval pads of this plant are reminiscent of one that you would find in a southern desert, while its edible, pear-shaped fruit is a juicy treat for small mammals such as rabbits, whose droppings are the plant’s primary means of seed dispersal.
But the shade-intolerant species grows only in dry, sandy soils in a zone between the water’s edge and leafy inland vegetation. Intense winter storms, which are increasingly projected, could soon wash this cactus right out of Canada.