[Mike]

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by David Suzuki 04.16.04

Recently, I wrote about a report from Birdlife International that
described how birds around the world were in trouble. The authors
noted that birds were an indicator species—canaries in the coalmine,
you might say—and they argued that if birds were faring poorly, then
other species, and the environment in general, probably weren’t doing
so hot either.

Just days after the report, results of a long-term study of bird,
butterfly and plant populations in Great Britain were published in
the journal Science. The results confirmed that, in Great Britain at
least, many bird species are indeed declining. But even more
disturbing, the researchers found that birds and other vertebrates
may not necessarily make good indicator species because lesser-known
creatures, like insects, seem to be faring much worse.

For the Great Britain study, researchers looked through 15 million
records of species amassed by some 20,000 volunteers. Over 40 years,
these volunteers kept detailed records of more than 3,000 separate
ten-square-kilometre test areas across the country. Great Britain is
the only place in the world where such detailed records have been
maintained for so long.

After studying the data for a year, researchers concluded that 28 per
cent of plant species and 50 per cent of bird species have
disappeared from at least one study area. Butterflies fared the
worst, with 71 per cent of those species disappearing from at least
one area over the past 20 years. In fact, two butterfly species went
extinct from Britain during the study period, as did six native
plants.

These findings are disturbing because insects account for more than
half of the known species on the planet. According to the
researchers, if insects are disappearing faster than birds, then
biologists have actually been underestimating the loss of life on
Earth, thus “strengthening the hypothesis that the natural world is
experiencing the sixth major extinction event in its history.”

While the last major extinction event occurred when an asteroid
collided with the planet some 60 million years ago, current
extinction levels have a much more mundane cause—human activities.
Sometimes the effects of these activities are obvious, like when we
fill in a wetland to build a parking lot. Others are more subtle. For
example, results of a study published in Science found that excess
nitrogen from intensive agricultural production and air pollution in
Great Britain is reducing plant biodiversity by creating conditions
more favourable to plant species that are better adapted to high
nutrient levels.

When most of us think of species extinction, we tend to think about
the big, charismatic species that we feel an affinity towards,
species like tigers, gorillas and whales. But plants and insects form
the backbone of biodiversity on the planet. To a certain extent,
everything else, including us, relies on them. Humans evolved at a
time of plenty on Earth. A stable climate, bountiful natural
resources, high levels of life diversity and vibrant ecosystem
services have all helped provide us with everything we needed to
develop our modern society. By degrading these services and driving
so many species to extinction, we put our own future in peril.

The good news is that if humans are causing the problem, we can still
fix it. It won’t be easy, but it’s not impossible either. Across
Canada, municipalities are banning the cosmetic use of insecticides
and herbicides. That will help. As we learned from the Great Britain
plant study, reducing air pollution and developing more sustainable
agricultural practices will help too. And Canada’s new species at
risk act will help, if it ever shows some teeth. These are a start,
but we have along way to go. If butterflies and plants are indeed
canaries in the coalmine, we don’t have any time to lose.