小蓝视频

Skip to content

Aflockalypse now: mass animal die-offs

On New Year's Eve, 5,000 red-winged blackbirds dropped out of the sky in Beebe, Arkansas. Necropsies revealed no evidence of poisoning but did indicate the birds had suffered massive internal trauma.
GN201110110129944AR.jpg

On New Year's Eve, 5,000 red-winged blackbirds dropped out of the sky in Beebe, Arkansas. Necropsies revealed no evidence of poisoning but did indicate the birds had suffered massive internal trauma. Days later, fishermen observed schools of fish floating belly up on Chesapeake Bay. In England, tens of thousands of dead crabs washed up on local beaches, and reports come in almost daily of penguins, turtles, and even dolphins dying unexpectedly in the wild. Are these events signs of the "aflockalypse", as the media have dubbed the recent die-offs? The answer is yes. And no.

Our inherent love and respect for the natural world compels us to take notice when animals die in large numbers, but observations going back more than a century suggest that the mass-mortality events of recent weeks aren't as unusual as we might think, and they are often the result of natural causes, such as adverse weather, disease outbreaks, or stress associated with long-distance migration.

In analyzing bird counts, journal records, and other observations dating back to the late 19th century, European researchers found frequent reports of deaths of birds in the hundreds and thousands. One massive kill occurred in spring 1964, when an estimated 100,000 king eiders, representing nearly a tenth of the species' western Canadian population, perished in the Beaufort Sea. These large, beautiful ducks starved when pools of open water among the sea-ice re-froze suddenly, preventing them from getting to the food in the water below. More recently, an estimated 40,000 individual birds from 45 different species were killed on April 8, 1993, when a tornado crossed their migration routes off the coast of Louisiana.

While the sudden death of wildlife in great numbers is alarming, the unravelling of entire food webs is happening all around us and every day - but in a far less obvious manner. With every patch of forest cut, wetland drained, or grassland paved, our ongoing destruction of wildlife habitat is leading to population declines, and even driving some species to extinction.

According to the experts, more than 17,000 plants and animals are threatened with extinction because of human activity, mostly through habitat loss. This includes 12 per cent of all known birds, nearly a quarter of known mammals, and a third of known amphibians. Climate change is predicted to sharply increase the risk of species extinction within our own children's lifetime. According to the Intergovernmental Panel on Climate Change, 20 to 30 per cent of plant and animal species assessed will likely be at increased risk of extinction if global average temperatures continue to rise with escalating emissions of carbon pollution.

This wildlife crisis has been described as a silent epidemic by scientists like famed Harvard entomologist E.O. Wilson, because it receives so little attention from governments. The David Suzuki Foundation recently released a study of government records showing that nearly half of all known wildlife species in British Columbia are at risk, including grizzly bears, caribou, and orca whales. Yet, B.C. has no endangered species law to protect its wildlife and habitat from logging, mining, urban sprawl, and other human activity.

Canada has a federal endangered species law, but the government is dragging its feet on implementing it. As a consequence, some wildlife populations, like the northern spotted owl in southwestern B.C., have declined precipitously under the watch of our politicians and are now on the verge of extinction in Canada.

The unsettling events of recent weeks reveal the inherent vulnerability of wildlife to sudden and dramatic population declines, often as a result of natural causes. This is all the more reason to ensure we don't exacerbate the challenges faced by wildlife in an increasingly busy world. We need to reduce the environmental stressors that we impose on wildlife, so that they can better cope with and survive the challenges they face every day. We need to eliminate dangerous pesticides and other toxic materials, protect the habitat of endangered plants and animals like caribou, and get serious about tackling climate change.

It's good that people are concerned about the recent animal die-offs, but if we really care about the future of wildlife, we need to start paying more attention to our own role in the extinction crisis - and urge our elected officials to take concrete steps to protect the biological richness with which our planet is blessed.

Learn more at www.davidsuzuki.org.

push icon
Be the first to read breaking stories. Enable push notifications on your device. Disable anytime.
No thanks