It seemed that this spring the skies were unusually quiet of birdsong.
April, May and June is usually a noisy – and lovely – nesting time. But where were all the colourful migratory birds that herald the arrival of spring, the nest building activity, and the thrill of their ancient songs? Where were the barn swallows, grosbeaks, flickers, wild pigeons, and hummingbirds? Song birds usually fill the trees in spring and there are usually hummingbird line-ups at the feeders from the end of March onwards as dozens of them hover, pushing for their turn. But this spring, we only saw two. Raptors – eagles, hawks, owls, and turkey vultures – seemed to be relatively plentiful but something was amiss.
I thought of Rachel Carson’s prophetic classic book ‘Silent Spring’ which, this year, celebrates its 50th anniversary since its release. Has the wisdom of her words that warned of birds’ demise because of pesticides and habitat loss come back to roost?
This summer, the first ever report State of Canada’s Birds 2012 was released by the North American Bird Conservation Initiative, Canada. The report, which draws on 40 years of data, found that, overall, Canada’s bird species have declined by 12 per cent since 1970. Some 44 per cent of species have declined, 33 per cent have increased and 23 per cent are holding their own.
While raptor populations (i.e., eagles, hawks, owls, falcons) have increased due to direct conservation work, especially in pesticide control, grassland birds are in decline due to habitat loss while shorebirds have declined by almost half. Aerial insectivores – birds that feed on insects on the wing such as swallows and flycatchers – have declined the most but the reasons are still unclear. Some waterfowl populations such as the Canada goose have doubled yet the great blue heron is strongly decreasing
“Overall, more species are decreasing (44 per cent of species in Canada) than increasing (33 per cent),” the report stated. “Some groups have severely declined, including grassland birds, migratory shorebirds, and aerial insectivores. These groups have all decreased by more than 40 per cent, on average, and some individual species in these groups have decreased by more than 90 per cent.”
The Rufus hummingbird, once so frequent at our feeders, has declined 63 per cent since 1966.
The reasons are many and varied. Loss of forests, wetlands, breeding grounds, and southern wintering habitat, pesticides, acid rain, and migration dangers are all factors in the mix.
Here on the west coast, many species have declined by 10 per cent and, in regions throughout the province, forestry, agriculture, resource extraction, and urban and industrial spread all put pressures on bird habitat. Climate change has influenced the spread of the mountain pine beetle and the report indicates that the reduction of the mature pine forest will be over 90 per cent by 2015.
Fixing the problem will take the willpower of everyone from homeowners with backyards planted with fruit bushes, nesting trees and feeders to conservation projects to restore and protect riparian, woodland and grassland habitat, foster nesting areas and support environmental policies that are bird friendly.
We could take a cue from Europe too. Conservation grazing programs use large grazers such as horses to graze wetlands back to health. The program has been successful in the U.K where horses’ eating habits leave stands of grasses at various heights and thicknesses, allowing sunlight to reach the soil and trigger seed germination. The mix of grasses, sedges and reed heights creates a diversity of ecological niches, providing food for other animals and enticing rare birds to return.
Conservation programs work but clearly there’s an urgent need for much more to be done to protect bird habitats.