In northern Manitoba, black bears, grizzly bears and polar bears are now living together

Awwww. Image: Getty.

North America’s three bear species – black bears, grizzly bears and polar bears – don’t typically live in the same place. But in Wapusk National Park, on the west coast of Hudson Bay in northern Manitoba, we caught all three bears on camera – for the first time.

My colleagues and I began studying the bears in Wapusk in 2011, after more polar bears than expected began visiting new field camps in the park. We used remote cameras – a widespread, economical and non-invasive tool for studying wildlife – to find out why and when the polar bears were visiting these camps.

The cameras picked up more than 366 visits by polar bears to the camps in five years. They also detected other bears.

A bevy of bears

Wapusk is best known for its polar bears. They come ashore in the summer and autumn when the sea ice in Hudson Bay melts. Some stay for the winter to den in the permafrost where they give birth. What we see on the cameras reflects that pattern.

But Wapusk also lies along the northern edge of the boreal forest, where black bears are well established. We saw them too, but we were surprised that their visits to our most southerly cameras, on the Owl River, were almost as numerous as those by polar bears.

Grizzly bears visited all three study sites along the coast of Wapusk National Park. Image: Douglas Clark/creative commons.

What was new to us were the grizzlies. It wasn’t just one or two transient bears, but several, and we suspect at least one of them may be denning there.

Barren-ground grizzly bears have been expanding their range across the Arctic in recent decades. In Wapusk, they’ve been increasingly frequent since the 1990s, and have even shown up in the nearby town of Churchill.

Ecosystem convergence

There’s much our observations don’t tell us, but they are significant for conservation efforts and, more fundamentally, for understanding what to do with these new ecological insights.

Three dynamic ecosystems – forest, tundra and ocean – converge at Wapusk, and all are changing quickly as the Arctic warms.

What we’ve seen in Wapusk is consistent with how researchers expect northern carnivore populations to respond to climate change. The waking life of all bear species is governed by their need to accumulate fat stores for the next hibernation, so this overlap is most likely a response to changes in the availability of bear foods. Which foods, however, we don’t yet know.

Three polar bears walk past a camera trap in Wapusk National Park. Image: Douglas Clark/creative commons.

We also don’t know how these species interact with each other, but we predict that grizzlies will benefit most since they dominate both other species elsewhere.

Grizzly bears have displaced and eaten black bears and polar bears in other places, and polar-grizzly hybrids have been documented in the Northwest Territories. It’s clear that the potential for hybridization exists in western Hudson Bay too.

Polar bears and grizzly bears face conservation challenges in many parts of Canada. Learning more about they way they interact with each other – and their surroundings – would probably tell us more about why they are now inhabiting the same place.

Controversial change

But how might we use this information?

When environmental changes occur in national parks, they often become controversial. People often assume the conditions present when the park was established, or the status quo, are “baselines” that must be protected, even though they may just be snapshots in ecological time.

Change has become increasingly central in ecological theory, and its implications have produced heated debate within the conservation community.

Black bears are well established in the boreal forest of Wapusk National Park. Image: Douglas Clark/creative commons.

This matters for the grizzly because its expansion into the Arctic has been portrayed as a threat to polar bears. Some argue such a threat should be removed.

In 1998, when I worked in Wapusk, I was told by a manager to get rid of the first grizzly we saw. (I didn’t.)

Such actions might not be wise since the long and complex evolutionary relationship between grizzlies and polar bears suggests their populations have, at times, benefited from the other.

Instead of looking at this new range overlap as a risk to any of the bears, my colleagues and I think it should be viewed as an ecological response to environmental change that needs to be better understood.


What’s at stake?

While locals may not be surprised by this scientific observation of the three bears, it is a novel situation that we can learn from – and one that matters beyond northern Manitoba.

Climate change will continue to move species around and create new combinations of them. It’s no easy task for wildlife or park managers to determine which environmental changes are desirable and which aren’t.

Wapusk, however, is a co-managed park that aims to integrate scientific and traditional knowledge with human values. It is equipped for addressing these hard questions. And the question of how to navigate increasing environmental variability more effectively – while recognising the stakes local people have in these conservation decisions – is the biggest challenge environmental managers face today.

This particular story of the three bears isn’t over, and we don’t know how it will end. Consequently, we need to bring a heavy dose of humility to answering the scientific and societal questions the three bears have handed us.

The Conversation

Douglas Clark, Centennial Chair in Human Dimensions of Environment & Sustainability, University of Saskatchewan.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 
 
 
 

These maps of petition signatories show which bits of the country are most enthusiastic about scrapping Brexit

The Scottish bit. Image: UK Parliament.

As anyone in the UK who has been near an internet connection today will no doubt know, there’s a petition on Parliament’s website doing the rounds. It rejects Theresa May’s claim – inevitably, and tediously, repeated again last night – that Brexit is the will of the people, and calls on the government to end the current crisis by revoking Article 50. At time of writing it’s had 1,068,554 signatures, but by the time you read this it will definitely have had quite a lot more.

It is depressingly unlikely to do what it sets out to do, of course: the Prime Minister is not in listening mode, and Leader of the House Andrea Leadsom has already been seen snarking that as soon as it gets 17.4m votes, the same number that voted Leave in 2016, the government will be sure to give it due care and attention.

So let’s not worry about whether or not the petition will be successful and instead look at some maps.

This one shows the proportion of voters in each constituency who have so far signed the petition: darker colours means higher percentages. The darkest constituencies tend to be smaller, because they’re urban areas with a higher population density.

And it’s clear the petition is most popular in, well, exactly the sort of constituencies that voted for Remain three years ago: Cambridge (5.1 per cent), Bristol West (5.6 per cent), Brighton Pavilion (5.7 per cent) and so on. Hilariously, Jeremy Corbyn’s Islington North is also at 5.1 per cent, the highest in London, despite its MP clearly having remarkably little interest in revoking article 50.

By the same token, the sort of constituencies that aren’t signing this thing are – sit down, this may come as a shock – the sort of places that tended to vote Leave in 2016. Staying with the London area, the constituencies of the Essex fringe (Ilford South, Hornchurch & Upminster, Romford) are struggling to break 1 per cent, and some (Dagenham & Rainham) have yet to manage half that. You can see similar figures out west by Heathrow.

And you can see the same pattern in the rest of the country too: urban and university constituencies signing in droves, suburban and town ones not bothering. The only surprise here is that rural ones generally seem to be somewhere in between.

The blue bit means my mouse was hovering over that constituency when I did the screenshot, but I can’t be arsed to redo.

One odd exception to this pattern is the West Midlands, where even in the urban core nobody seems that bothered. No idea, frankly, but interesting, in its way:

Late last year another Brexit-based petition took off, this one in favour of No Deal. It’s still going, at time of writing, albeit only a third the size of the Revoke Article 50 one and growing much more slowly.

So how does that look on the map? Like this:

Unsurprisingly, it’s a bit of an inversion of the new one: No Deal is most popular in suburban and rural constituencies, while urban and university seats don’t much fancy it. You can see that most clearly by zooming in on London again:

Those outer east London constituencies in which people don’t want to revoke Article 50? They are, comparatively speaking, mad for No Deal Brexit.

The word “comparatively” is important here: far fewer people have signed the No Deal one, so even in those Brexit-y Essex fringe constituencies, the actual number of people signing it is pretty similar the number saying Revoke. But nonetheless, what these two maps suggest to me is that the new political geography revealed by the referendum is still largely with us.


In the 20 minutes it’s taken me to write this, the number of signatures on the Revoke Article 50 has risen to 1,088,822, by the way. Will of the people my arse.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and on Facebook as JonnElledgeWrites.

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