In nature, predators usually go after the weakest of the prey — the oldest or youngest, the injured or ill. It makes sense; these animals are easier to catch, even if they're not always the meatiest.
We humans are different. We're often out to prove something, and so, with our fancy hunting or fishing gear, we go after the biggest and strongest animals — the trophy bucks with bigger horns, the bears with the best coats, or the biggest salmon or halibut.
In the natural order, the predator-prey relationship can ensure that wildlife populations stay strong, as the weakest animals get culled while the strongest and healthiest survive to pass on their genes.
Some hunting and harvesting done by humans has the opposite effect. New research published in the Proceedings of the National Academy of Sciences shows that many of our current hunting and fishing practices not only reduce population numbers but also cause dramatic and often negative changes in the behaviour, size, and characteristics of targeted species.
Researchers from Canadian and American universities looked at 29 earlier studies, mostly of fish but also of larger animals such as bighorn sheep and even some plants, and found that rates of evolutionary change were as much as three times higher in species that are hunted and harvested by humans.
We've long known that unsustainable rates of hunting and fishing can devastate wildlife populations and fish stocks. Just think of the Atlantic cod fishery and the looming crisis in the Pacific salmon fishery. Now, as the new study shows, we're not just affecting the numbers; we're also having an impact on the characteristics of the animals themselves, such as body size and the age at which they reproduce. We have become a part of the evolutionary process, and that has huge implications when you consider how ignorant we are about the web of living things.
It's an important issue to consider when we look at hunting and fishing practices and regulations. When rules are overhauled to allow hunters to take even more species of animals, we have to think hard about what effect that may have on biodiversity and on evolution.
For example, the Ontario government recently posted a proposal to radically overhaul hunting rules in Kawartha Highlands Signature Site Park, a large protected area in the province. These changes would expand the existing hunting season for traditional "game" species such as black bears, and would allow hunters to kill previously protected non-game species, such as foxes, weasels, groundhogs, porcupines, raccoons, skunks, and a range of amphibians, common bird species such as crow and grackle, and snapping turtles. The increased hunting opportunities would, in turn, trigger an increase in ATV use in the park.
While I don't hunt (although I love fishing), I'm not opposed to sustainable hunting and fishing for subsistence and even commercial purposes. But we should be clear: the Ontario government's proposed hunting rules for Kawartha Highlands Park are not about putting venison on the table. This is about expanding the human footprint within a protected area. Doing so is hardly consistent with the park's stated mandate to "preserve, protect and enhance the natural composition and abundance of native species, biological communities and ecological processes in the Park." I'd bet it's also at odds with the values of most citizens in Ontario, who believe that parks should provide a safe haven for wildlife — especially considering that more than 90 per cent of Ontario is already open for hunting.
What really steams me is that the proposed plans are at also odds with a key principle of sustainable wildlife management: that we should keep common species common to ensure they aren't placed at risk in the first place. For example, the Committee on the Status of Endangered Wildlife in Canada, or COSEWIC, the expert and independent science body that advises governments on species at risk, has just assessed snapping turtles as a species of special concern. The turtles are found within Kawartha Highlands Park and could be hunted if the new regime is approved, even though they are particularly vulnerable to human activities.
Parks like Kawartha Highlands Signature Site are an integral part of a commitment to maintain ecological integrity. Wildlife species in Canada are already under enormous pressure, due mainly to habitat loss and fragmentation. We need to act in a precautionary way now to minimize our actions that affect the ability of species to survive and evolve.