When mammals are threatened, we are threatened | Science Matters | David Suzuki Foundation
Photo: When mammals are threatened, we are threatened

Polar bears and grizzlies are particularly susceptible to decline because they require a lot of food for energy, they are large, and they reproduce infrequently and have few offspring when they do reproduce (Credit: rubyblossom via Flickr).

By David Suzuki with Faisal Moola

We humans sometimes forget that we are animals. We're mammals, and like all mammals, and indeed all animals, we are connected to and dependent on the web of life. When part of that web is in danger, we are all in danger.

And our mammal cousins are in danger. According to the International Union for Conservation of Nature, one quarter of the world's 5,487 known mammalian species face extinction in 30 years if we don't act now to protect them. This includes many of the planet's apes and monkeys; bears such as polar bears, sun bears, and pandas; and dozens of marine mammals, such as sei and fin whales.

The causes of this biological crisis include habitat loss and damage, introduction of invasive species, pollution, harvesting, and climate change. Because many mammals are large (elephants, hippos, rhinos), exhibit extraordinary intelligence (chimps and gorillas), or have a ferocious nature (lions, tigers, and bears), we have often assumed that they are somewhat resilient to human impacts. This couldn't be further from the truth.

Scientists now believe that the biology of many mammals contributes to their vulnerability. For example, polar bears and grizzlies are particularly susceptible to decline because they require a lot of food for energy, they are large, and they reproduce infrequently and have few offspring when they do reproduce. Human impacts such as unsustainable hunting or habitat destruction put more pressure on the ability of these species to survive.

There is some good news, though. The IUCN assessment showed that "concerted conservation efforts" can bring mammals back from the brink. For example, by reintroducing the black-footed ferret into eight western U.S. states and Mexico, the U.S. Fish and Wildlife Service managed to move the animal from the list of animals that were extinct in the wild to the endangered list.

But who cares about the black-footed ferret, or the wild horse, or the African elephant? We humans are not in danger of extinction, are we? Humans are the most numerous mammal species and our influence now extends to every square inch of this planet, as well as the atmosphere. But if we think we can survive such a rending of the web of life as the extinction of one quarter of all mammal species, we're living in dreamland. The long-term consequences could be catastrophic because, as the top predator on the planet, our survival and well-being depend on the health and well-being of all life that supports us. (And remember that long-term in this case is only 30 years!)

Even if we look just at the short term, we see that it's in our best interest to protect our fellow animals. As Dr. Jane Smart, head of the IUCN's species program, points out: "The longer we wait, the more expensive it will be to prevent future extinctions. We now know what species are threatened, what the threats are and where — we have no more excuses to watch from the sidelines."

The rapidity and scale of response to failing financial institutions shows that we are capable of action when we perceive danger. Well, the extinction crisis on the planet imperils our very survival.

In Canada, we've seen some recent progress in the area of habitat protection. The federal government announced that it will protect 10.1 million hectares of boreal forest in the Northwest Territories, and the Ontario government announced that it will protect 50 per cent of its intact northern boreal forest.

But, as always, we must do much more to ensure that all species at risk survive. Besides the mammals, the IUCN added the iconic Pacific sockeye salmon to its red list of endangered species. People on the West Coast know that the salmon is the lifeblood of coastal ecosystems, providing food for people, bears, and birds, and fertilizer for the forests. That's a perfect example of how interconnected our web of life is.

We have to make some big changes in the way we do things on this finite planet. We can't just keep destroying habitat, polluting water and air, and killing fish and other animals faster than they can reproduce. And because we are all connected to this fragile web, we need to protect animals and their habitat not just for their sake, but for our own as well.

October 17, 2008
http://www.davidsuzuki.org/blogs/science-matters/2008/10/when-mammals-are-threatened-we-are-threatened/

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