Keeping ecosystems healthy means giving them enough space to thrive
Science | by Gregory Beatty
When it comes to impending ecological catastrophes, climate change is probably the one that gets the most publicity.  It’s not the only environmental challenge facing us, though. We’re also in the midst of what scientists describe as a sixth mass extinction — an ecological event where thousands of plant and animal species around the world are in danger of disappearing.
Many are already gone. The passenger pigeon, the quagga, the dodo, the Tasmanian tiger, the great auk and Stellar’s sea cow (a 30-foot-long, 10-ton Arctic relative of the manatee that was hunted to extinction within 27 years of their discovery by Europeans) are all gone. And just two months ago the last male northern white rhinoceros — a species decimated by poaching and habitat loss — died of old age. Two female northern white rhinos remain, but without a male in the mix, the subspecies is officially extinct.
Sudan’s death made global headlines but it was far from an isolated occurrence. The explosive growth in human population (from two billion in 1927 to 7.6 billion today) and our relentless plundering of Earth’s natural resources for material gain, is wiping out species at an incredible pace. Human-caused climate change, which is disrupting plant and animal habitat, is obviously not helping.
To reverse this sorry trend and preserve the biodiversity that’s both intrinsically valuable as well as essential to the sustainability of life on Earth, scientists and environmentalists have begun to advance the idea that humanity must surrender half of the planet to nature.
Sound radical? Maybe. But so is wiping out plants and animals at a thousand times the normal rate of extinction.
If we don’t act now, the future promises to be bleak.
Nature Needs Half
“The big idea is that as the 21st century unfolds we have to get our relationship with nature right because it’s going very wrong,” says Harvey Locke, a Canadian spokesperson for the international organization Nature Needs Half. 
Locke, who will be in Saskatoon May 25 for the annual Nature City Festival, will outline the challenge humanity faces, the positive steps that have been taken so far, and what we must still do to give nature a fighting chance.
At present, says Locke, Earth can be divided into three states. In areas such as Antarctica, the Amazon and Congo Basin, wilderness is largely intact. Then there are intermediate areas, where the environment has been broken up, but most of the natural habitat is still there. National parks such as Banff and Jasper fall into this category.
Then there are areas such as the Canadian prairies, where the habitat has been radically transformed and native species are facing extinction pressure.
“One thing we have got right is the realization that when we create parks and other protected areas, we protect the things that are there,” says Locke. “They are an absolute precondition to success, but if they become islands in the landscape they are not sufficient to protect species and their ecosystems.”
“We need to think about networks of protected areas, we need to think about what’s called connectivity and how species move from A to B,” he says. “It doesn’t have to be just one giant protected area. But we have to think about how the whole landscape works and how natural flows go across the landscape, from the way species move to how ecological processes work.”
The more we learn about the natural processes that regulate the quality of air, water, soil and other components of nature, it sometimes seems, the more complicated the picture becomes. So the scientific investigation of those processes, in consultation with Indigenous peoples in wilderness areas, is a key part of the Nature Needs Half movement.
But our need to gather further knowledge in this area is no excuse for inaction now, says Locke.
“We know a fair bit already. What we seem unable to do is act on what we know. Canada has to meet what’s called Target One, which is our commitment to the world under the Convention of Biodiversity. That means we need to protect 17 per cent of the land and water by 2020. Right now, we’re at 12 per cent. So we’ve got a lot of work to do.”
In the 2018 federal budget, the Liberal government committed $1.3 billion over five years to protect land, water and species at risk. That will help us reach our commitment. But in a global context, Canada lags says Locke.
“There are countries like Tanzania in Africa, for instance, that have protected far more than 17 per cent of their land and water. Bhutan in the Himalayas has protected over half of their country in an interconnected way. And Brazil, a country roughly the same size as Canada but with [six times] our population, has done far more as well.”
Cities have a role to play in the Nature Needs Half movement too. Often, says Locke, they were built in biologically productive areas. With proper management, he says, they can provide viable wildlife habitat.
“There’s an interesting movement in London to declare it a national park city,” says Locke. “It has a lot of support from municipal politicians. What they’re saying is, ‘We have a lot of public green space, nature reserves, gardens, and if we thought more about nature and how that was managed, it would make a tremendous difference in the city.’”
Boulder, Colorado; Mumbai, India; and Nairobi, Kenya are three other cities that have made a major commitment to preserve wildlife habitat.
On an individual level, home and business owners can make landscape decisions that create productive habitats, too.
One final key to the Nature Needs Half movement is international cooperation. Countries with coastal waters have the right to establish 200 km marine protection zones. To protect what are called the high seas, though, we need coordinated international efforts.
“We need the United Nations to come to an agreement,” says Locke. “Canada can play a role in that. We also need to protect our own marine environment, including the Arctic Ocean. We should be protecting a huge amount of it now before the ice melts [from climate change] and all the competing interests from other countries start to descend on it.”
That same level of cooperation needs to happen on shared land borders to make sure that hunting ranges for predators, migration routes, water flows and other features of wilderness habitat are preserved.
The Yellowstone to Yukon Conservation Initiative is one example of countries working together to maintain habitat, says Locke. But while Canada is party to the agreement, he adds, we’re being outpaced by the Americans.
“Waterton-Glacier International Peace Park is on the border,” says Locke. “It’s an area a lot of Saskatchewan people have probably visited. But the Flathead Valley on the Canadian side has no protection, where it does have protection on the American side.
“The Americans have done more than us, and it’s our turn to step up.”
When you boil arguments against wildlife habitat conservation down to their essence, they’re often based on the idea that if we move too aggressively to restrict agriculture, oil and gas exploration, mining, factory fishing, urban sprawl and other profit-generating activities, the economy will suffer.
It’s the wrong way to look at things.
“Humans are dependent on nature whether we [admit] it or not,” says Locke. “We depend on nature for the air we breathe, the water we drink [and] for storing carbon as opposed to releasing it into the atmosphere which fuels climate change.”
In ways too numerous to mention, nature and Earth’s vast web of life provide ecological services that have been crucial to our survival from our earliest days as clever primates.
Unless we act soon, though, those services are at risk of being lost.
“The problem we have right now is we’re just looking at Earth as this giant buffet for us to eat instead of it being our home,” says Locke. “That’s the shift we have to make conceptually. This is our home, and we have to look after it.”
 ^ Editor’s (foot) note: I challenge readers to find a lede like this in any other Saskatchewan publication.