Lawrie McFarlane: No foxes or coyotes on Vancouver Island

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Why are there no foxes or coyotes on Vancouver Island, when these animals are present in good numbers on the Mainland? Couldn’t they swim this far?


We have raccoons and squirrels. If they made it here, why not coyotes and foxes?


You would think the east coast of our island would be perfectly suited to these predators. Look at all the urban deer on the Saanich Peninsula that coyotes could feast on. Equally, the farmland in the Comox Valley seems a natural fit for foxes.


True, both of these species were traditionally rural rather than suburban dwellers. Yet the modern era has seen both animals move close to, and even into, suburban habitats. They’re increasingly common in Lower Mainland residential areas, often too close for comfort.


And the mystery doesn’t stop there. Why do we lack some of the smaller mammals, such as badgers, skunks and porcupines, while we do have marmots and otters? If some of the weaker brethren found their way here, why didn’t others?


It seems several factors are at work. Offshore islands always have a narrower range of wildlife species than the adjacent mainland.


There are 19 mammal species on Vancouver Island, but 32 in other regions of the province. You see this contrast also on Haida Gwaii, which has just seven species (and likewise, no foxes or coyotes).


But that doesn’t account for our peculiar mix of animals. Two other explanations play a role.


First, the minimum number of animals required to sustain a breeding population is much larger than once thought. The traditional view was that a few hundred would suffice.


However, more recent research suggests that to guard against genetic damage caused by inbreeding, and to provide a cushion against harsh winters, you need about 4,000 animals.


But Vancouver Island doesn’t offer sufficient habitat to maintain that many foxes or coyotes, and not even close to it. Ditto badgers and porcupines.


Raccoons, by contrast, are a semi-aquatic species. They like being around lakes, rivers and estuaries, of which we have our share. They also do well in urban settings, digging through trash cans and pinching backyard chickens.


Second, there is the matter of predation. Foxes are killed by coyotes, and coyotes are preyed on by wolves — and we do have wolves on Vancouver Island. It’s possible there were originally populations of these smaller predators, but they lost a battle for survival.


This is happening in Yellowstone National Park, where reintroduced wolf packs have decimated the local coyote population.


Again, cougars, of which we have the largest number per square kilometre in North America, readily kill porcupines. And owls, which are also abundant in our forest-fringe communities, eat their share of skunks — partly because their paths frequently cross, since both are nocturnal.


In short, while it might appear our mix of species isn’t readily explainable, there are in fact some biological traits that do reveal the reasons.


All the same, I fantasize about rounding up 40 or 50 coyotes and letting them loose in central Saanich to eat all the deer. I mentioned this to the biologist who explained the facts of Island wildlife to me.


Yup, he said, for a year or two they’d make a dent. But then they would run out of deer and move on to family pets (or even family members, at least the little ones). After that, they’d die out.


Too bad, though. If we leave this problem to municipal politicians, there will never be a solution. And who wouldn’t want to see an invading army of foxes making inroads on the Canada-goose population?


Nevertheless, if you were wondering, that’s why we have no foxes and coyotes on Vancouver Island.


jalmcfarlane@shaw.ca

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