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049 A look at polar bear ecology, cougars that aren’t solitary, and does shooting problem bears work

In this episode, I look at some of the reasons so many people flock to Churchill every year to see polar bears. I also look at a new research study that has shown that cougars are not nearly as solitary as biologists once believed. Finally, I examine a study looking at whether shooting problem bears actually solves the problem of problem bears

Three Weeks With Polar Bears

In my last episode, I mentioned that I was heading off to Churchill, Manitoba to work as a polar bear viewing guide with Frontiers North Adventures. The trip was amazing and a fabulous opportunity to learn more about Canada’s north as well as about some amazing bears and the landscape that forged them.

I thought I’d share a little bit about Churchill and the bears that travel there every autumn, year after year, waiting for the ice to form on Hudson Bay.

Why do they gather at Churchill? It’s really a collection of geography and ocean currents that make the area around Churchill the first place on Hudson Bay to freeze, giving bears the earliest possible access to the ice in order to feed on ringed and bearded seals.

The town of Churchill is situated near the mouth of the Churchill River. This major freshwater river provides some of the earliest ice into the bay as freshwater freezes at a warmer temperature than does salt water.

Freshwater, as we all know, freezes at 0C. Saltwater though inhibits freezing until the temperature drops to around -2C. It also freezes in a different way. Since ocean ice is subject to constant currents and tides, instead of a nice thin surface layer of ice forming, you see the surface getting progressively more and more slushy in appearance as the individual crystals of ice form and are constantly moved around with the movement of the water.

At this point, there is a river of freshwater ice pouring into the bay. Further north in Hudson Bay, the temperatures may be much colder, allowing ice to begin forming there in advance of this more southerly location. So why is Hudson Bay the first place to freeze solidly enough for polar bears to travel?

If you look at Hudson Bay from the International Space Station, there is a counterclockwise current that takes ice forming in the northern part of the bay and carries it south to the area around Churchill.

Eventually, you see a mix of fresh and saltwater ice being carried past the community and then one final bit of geography acts to trap the ice as it passes by.

South of Churchill is Wapusk National Park, the only National Park in Canada that is home to polar, grizzly, and black bears.

The town of Churchill and the northern-most portion of the park juts out into Hudson Bay and acts to capture the ice flowing southward.

It all collects in the area of the bay east of the townsite and quickly, if the temperatures, tides, and currents cooperate, the ice begins to form.

Always remember that sea ice is a living, moving thing. Most of the annual ice pack around Hudson Bay shifts and moves, often colliding with other ice. This creates cracks and openings in the ice called leads. These leads are one of the places that ringed seals will use as breathing holes.

For polar bears, they mean dinner. The bears around Churchill have not fed since the end of July when the ice on the bay melted. Polar bears don’t feed on land. All of the food that is important to them requires a solid ice surface in order for them to hunt.

Even the Latin name for polar bears, Ursus maritimus, meaning “maritime bear” reflects the fact that they are really considered a marine mammal rather than a terrestrial one.

Polar bears split off from Grizzlies some 125,000 years ago. In terms of evolution, that is just the blink of an eye. In that time, they developed a longer neck and snout to help in swimming. Its teeth became smaller and more jagged to help it tear up seal carcasses, and their frigid white habitat favoured those bears with lighter and lighter coats until they became the cream colour that we now see out on the tundra.

Surprisingly, polar bears are one of the few animals that are not snow white in colour. Their very light blonde colouration makes them much easier to spot than the arctic fox, arctic hare, willow ptarmigan, and snowy owls that share the tundra with them.

Having the opportunity to guide in Churchill is a lifelong dream. There is something magical that happens when you stare into the beautiful brown eyes of a polar bear from just a few metres away. It’s an experience that changes even the most jaded observer.

Polar bears have a very uncertain future. They have roamed the frozen surface of the arctic icepacks for 125,000 years. Just as the landscape shaped the bear, it also shaped the animals the polar bears feed upon.

Ringed seals are their major prey, at least in the western Hudson Bay population. They are the smallest seal, with adults weighing in at around 70 kg. Unfortunately, even these seals are very difficult to catch. The bears are currently heading onto the bay and are finally able to feed, but they will miss far more seals than they will catch for the next few months.

In the central Rockies, we talk about buffaloberries being the most important food allowing grizzlies to build their fat layers for winter. In Hudson Bay, it’s the pups of the ringed seals that are the real smorgasbord.

When the pupping season begins in April, the bears will begin to feed on the easily captured baby seals and this buffet will provide up to 2/3 of their annual caloric intake. Much like buffaloberries for grizzlies, seal pups are absolutely critical to the polar bear’s survival.

Polar bears don’t hibernate. Males and females with cubs never enter a den at all, but stay active 12 months of the year. Pregnant females will den up in November in order to give birth and nurture their tiny cubs but will emerge from the den in April, just in time to take advantage of the huge numbers of seal pups available for feeding.

Pregnant females will have been without significant food for around 9 months by this time and their milk is around 30% fat so nursing their cubs takes a huge toll on mom’s already depleted fat reserves. She will be very ready to head out in the spring for seal blubber.

Yup, you heard that right – seal blubber. The first few seals they catch will be fully consumed until they take the edge off their long hunger. Soon though, they’ll begin to eat just the blubber on the seals. The actual meat will be left for scavengers like arctic fox to finish off later.

Blubber is what it’s all about. They can very efficiently convert blubber into fat and, at the same time, blubber releases water when the bear digests it so they also don’t need to drink much water during this period.

Polar bears and ringed seals have evolved in lockstep with each other for 10s of thousands of years. If the landscape is the canvas upon which the painting of the north is created, the constant process of adapt and respond has honed these two animals into the unique creatures that we see today.

As one author put it: “where would the deer be without the wolf to whittle its swift legs”. Predator and prey and ice. It’s one of our greatest stories but is at risk of turning into one of our greatest tragedies.

This year, the ice is forming up nearly a month earlier than last year. Unfortunately, the trend is for the bears to lose more and more time to hunt. At the same time, the seals lose time for their young to use the ice pack to build blubber for them to stay warm in the frigid water.

The seals create birth lairs in snowdrifts that form atop their breathing holes. Warming climates mean these collapse earlier and earlier, exposing the pups to hungry polar bears.

Climate change is not something to worry about in the future, it’s something that is happening every day in the north.

I also witnessed another unfortunate side effect of warming of the north country – invasive species, in this case, the red fox.

The arctic fox is perfectly adapted to its northern home. It has one of the warmest coats of any arctic animal. In order to reduce heat loss, it has developed a smaller body size, shorter legs, and small ears. These are classic adaptations for animals living in cold climates.

Unfortunately, with warmer winters, red fox are moving in. They are twice the size of the tiny, house-cat sized, arctic fox and we watched as one red fox chased down and ate an arctic fox.

This is an interaction that would not be happening were it not for warmer winters. Red fox do not have nearly the cold tolerance of the arctic, but for the moment, the red fox is slowly wiping out the most southerly populations of arctic fox, forcing them further and further north. Eventually there may be a time when there is no place further to go.

I learned a great deal this year working with Frontiers North Adventures. They are the original creators of the tundra buggy and they operate incredibly ethical tours. As a naturalist, I loved the way that we didn’t approach the bears too close – we let them come to us. If we saw the behaviour of a bear change, then we stopped and left the site to the bear.

This is a time of extreme energy conservation for polar bears and we don’t want our actions to cause them to squander any additional energy resources.

The season is short, but if you’d like the opportunity to experience this amazing story first hand, then check them out at www.FrontiersNorth.com. I hope to see you there next fall.

Are Cougars Really Solitary Hunters

When we look at carnivores in the Rockies, we generally divide them into two groups; wolves which are social and cougars which are solitary. Cougars have long been considered the lone wolves of the cat family. They don’t socialize with other cougars and need to bring home their own bacon so to speak.

OK, sure, they do occasionally hang out together, but there is usually either sex involved or kick-ass, drag-down battles designed to settle territorial disputes. That’s it – no cat cuddles or kibble sharing.

Stay out of my territory unless yer looking for a cuddle or a bruisin’. These solitary hunters have vast territories with few opportunities to interact, except where accidents of geography and pheromones intersect.

How would anyone get an idea of whether they shared a howdy-do in the rare chance that they might bump into one another?

Well as it turns out, cougars are not nearly as solitary and antisocial as scientists have long believed. I love science. We live in a landscape where so many species interact in subtle, rarely observed ways that leave no record.

Like the old adage, “does a bear….in the woods”? Well, a recent stint in polar bear country answered that question for me…at least in the willows anyway. Wildlife biology has long been hamstrung by the simple fact that we can’t actually be out there to observe these rare interactions…or can we?

Every year, new technological advances give scientists a new way to observe, record, and understand the day to day interactions that historically have occurred without any scientific remark.

Perhaps one of the most important advances in the past few years has been related to wildlife cameras. Biologists can set up a camera in the wilderness and anything that wanders by can suddenly find itself the star of the show.

Twenty years ago, these cameras were a significant investment for biologists, but recently the cost has dropped to such an extent that hundreds can be deployed to look for a myriad of behaviours.

Ok, back to the story, cougars avoiding cougars.

In 2012, Mark Elbroch, the lead scientist for Panthera, a global organization focused on the conservation of wild cats like lynx and cougar, decided to see what cougars did when they were out and about.

He installed cameras throughout a 900 km area of Yellowstone and experienced one of my favourite scientific constructs – serendipity.

He wasn’t looking for social behaviour, but simply to get a better idea of what the cougars were feeding on in order to better understand how much they ate as well as what their impact would be on the wider Yellowstone ecosystem.

His cameras revealed some amazing discoveries. For instance, they showed that cougar kills attract a wider diversity of scavengers than any other carnivore. This means that they contribute more food to the local wildlife and birds than do the carcasses of wolves.

His cameras revealed that 10.9% of local birds and 28.3% of local mammals took advantage of the cougar kills. In total, he captured a total of 39 different birds and animals scavenging these carcasses.

He also discovered that this diversity was consistent when scavenger counts at other carcasses were compared. Let’s think about this. For every successful kill that a cougar makes in this particular area of Yellowstone, 39 different species benefit.

So their study was successful in their primary goal, but it was also successful in a much more surprising way. The cameras revealed that cougars may not be as solitary as biologists have always believed.

In 2012, one of his cameras showed a female cougar approaching the kill of another female. Amazingly, after a short time of hissing and posturing, both cats proceeded to feed on the same carcass.

This happened over and over for a day and a half. The two cats stayed in the area of the kill and continued to feed together. DNA analysis also showed that the two cougars were not related to each other either.

Now I know what you’re saying. This could have just been a fluke. Nobody’s ever seen this before so this was probably just an exceedingly rare occurrence.

Well after this discovery, Elbroch began to specifically look to see if other cougars socialized with their neighbours. In fact, between 2012 and 2015, he was able to capture images of 118 different incidents where two cougars socialized.

Previously, it was believed that cougars interacted only rarely, and in specific situations such as mating and territorial disputes. The belief was that these interactions are so brief that the cougars wouldn’t build any social strategies. Globally, 179 of 249 species of land-based carnivores are considered to be equally solitary.

This puts each individual within a population in the role of a competitor when it comes to food resources. This makes scarce resources that much more important in creating reasons for animals to be solitary. If there’s only so many elk, then I’m going to get my share before the others.

This study threw many of these presumptions on solitary animals into doubt. By looking at this single animal, perhaps there could be parallels with other apparently solitary carnivores around the world.

When we talk about social animals, we’re often talking about pack animals like wolves, however, in our human population, there are many degrees of social.

Even seemingly solitary people may have many social ties with others in widely varying degrees. They just don’t stand out as the usual definition of social.

Female and male cougars will make different decisions when determining their territories. Females are looking for a good place to raise young. That means that they need a range large enough to be able to consistently find enough food, but also that intersects with potential males for mating.

Male cougars are looking for a range that includes several females, while also excluding competing males from the same landscape.

When the first evidence of cougars socializing came out, it was believed that they must be related in some way. This study showed that the social behaviours extended well beyond any familial ties and included unrelated individuals.

As Elbroch considered the unique case of cougars, one of the most important aspects of their behaviour was the fact that they hunted prey several times their own size. This means that when a cougar kills a moose, for a time it has far more food than it could ever consume in one sitting.

As I’ve already mentioned, some 39 different types of mammals and birds are also lined up waiting for a piece of the kill. In nature, having a surplus of food can make a predator more tolerant of being crowded.

Pumas also maintain their territories for many years. This creates the opportunity for regular interactions with the same neighbouring cougars repeatedly during those years.

This study focused on cougars interacting at kill sites for two reasons. At the beginning of the study, it was noticed that cougars more commonly interacted at carcasses. Even more critical though was the ability to categorize the relationships. One cougar is the giver and the other cougar the receiver.

If cougars ARE social and regularly share kills, then is it a reciprocal behaviour. If I share my moose with you today, will you share your elk with me tomorrow?

To test these theories, they needed to be able to follow the cats as they travelled and determine when they were congregating. They fitted 16 cougars with satellite collars with 11 of the cougars sharing overlapping territories.

In the end, the interactions involved 9 females and 4 males. DNA studies showed that they were not related to each other so the interactions would have been unrelated to any familial ties.

Of the female cougars, older females appeared to be more tolerant than younger ones, but males benefitted far more than they reciprocated.

When it came to sharing a kill, a female that shared her food with another female was almost 8 times as likely to receive similar treatment when the tables were reversed.

The study also showed that a male that was familiar with both females was far more likely to be tolerated during these food sharing interactions.

Male cougars were not nearly as big on sharing. They tended to guard their kills and not allow females to share the food with them.

When two females met at a kill, the cats would usually meet, followed by a bout of posturing and hissing. This was followed by peaceful periods of calmly feeding beside each other.

When a male joined a female at a kill, they usually approached slowly and in a crouched position which made them look smaller than they really were.

By the end of Elbroch’s research, it was apparent that every single puma in the study participated in this sharing behaviour. They would tolerate a rival for long periods at a kill site

While the textbooks call cougars solitary, this study shows that perhaps we need to redefine the term. In times of plenty, solitary animals have little to lose by sharing the wealth. Sharing that is later reciprocated also benefits the cats over other scavengers waiting in the wings to finish off the carcass.

There are many solitary animals that have been witnessed feeding together when food is plentiful. I’m currently up in Churchill, Manitoba guiding polar bear viewing trips. Polar bears are well known to feed in groups when the carcasses of large whales wash ashore. A recent series of photographs taken on Wrangel Island in Russia showed more than 200 polar bears feeding on a single bowhead whale carcass.

Grizzly bears are well known to fish communally on salmon streams across the mountain west.

Social behaviour by cougars is only now coming to light, but it’s also a behaviour that makes sense. Cougars occupy territories with a wide likelihood of regularly encountering their neighbour.

Cooperation can help to reduce the likelihood of riskier territorial disputes when these interactions occur. At the same time, a solitary cougar is surrounded by other scavengers looking to steal as much of the meat as possible.

Sharing a kill today means that cougars in overlapping territories can essentially share the burden of making kills while still remaining largely solitary.

Hopefully, this study will spur an entirely new look at the social behaviours of animals believed to be solitary. Perhaps we’ll be surprised.

Next up…killing grizzlies is not the answer to human-bear conflict

Killing Grizzlies

Across the mountain west, all too often, bears that get into trouble are either removed or simply shot. These two decisions are the most difficult decisions any wildlife manager will ever make. Conservation officers usually enter the field trying to make a positive difference in the community and to help keep wild animals…wild!

There are many reasons for human-wildlife conflicts. They can range from individual problem animals, overpopulation and even a limited food supply. Current management practices can mean that individuals, as in the case of Bear 148 this summer, are removed from the landscape.

A recent study published in the Journal Scientific Reports, did not specifically look into bears on the eastern slopes of the Rockies, rather it looked at bear conflict in areas of British Columbia that contain salmon streams.

Grizzly bears don’t want to interact with people. We’re their only true threat. If that’s the case, then why do we end up in conflict situations? And are current management procedures consistent with the causes of conflict? Finally, do the current practices reduce future conflicts?

This study tested three different cases. The first proposes that conflicts are more commonly caused by individual problem animals. The second, that overpopulation is the primary driver and the third, that conflict is caused by changes in the local food supply or availability.

It also recognized that the number of bear-human conflicts varies year by year with some years having far more cases of negative interactions.

In this study, they learned that on years with reduced salmon runs, the number of human-bear conflicts increased. This is particularly true of the late summer and fall periods when bears go into a state of hyper-feeding known as hyperphagia.

Bears need to put on fat for the winter. This period of hyperphagia accounts for the vast majority of a bears annual caloric intake.

For coastal bears, these calories come from salmon. As they looked at spikes in bear conflicts, they noticed that the spikes usually coincided with years of poor salmon runs.

Studies on collared bears showed that they were more commonly attracted to townsites in years when food resources were scarce. In years of plenty, these same bears avoided people.

We can see this same parallel in Canmore in recent years. Locally, we are very focused on the story surrounding Bear 148 this past summer. It was a tragic story that helped to mobilize the community towards making sure that she is the last to suffer this fate.

Here’s the reality. She isn’t. Conservation Officers have one of the toughest jobs in resource management. They often get none of the credit and all of the blame. 148 was a tragic story that is not the fault of local CO’s, but it’s the fault of each and every one of us that live in Canmore.

We need to hold our neighbours accountable for violating closures and ignoring bear warnings.

As heartbreaking as this summer was, let’s look back to 2015 when we had an utter failure of the buffaloberry crop. By the beginning of September, 12 black bears had been relocated to areas further away from Canmore. The bears were desperate. Lacking buffaloberries, they were attracted to the many fruit trees within the community.

2017 has been predominated by the loss of one iconic bear. We need to remember that in other years the number of human-bear conflicts is often many times higher.

The berries will be here every year. We need to continue to work to make sure that the number of bears either killed or translocated is minimized as much as possible.

This study showed that in cases of higher than normal conflict numbers, killing individual bears did not reduce conflict in future years.

Thankfully here in Alberta, the bias in bear management is towards saving bears. In many areas of British Columbia, 148 would have been killed much earlier in the management process.

This year alone, some 500 black bears were euthanized in the province of British Columbia. While there are bears that need to be euthanized. There are still more that are simply food-stressed and trying to fulfill their minimum caloric intake.

We all need to support Alberta Environment and Parks efforts to keep bears on the landscape. We won’t always like their decisions, such as their recent decision NOT to intervene in the case of a small black bear showing signs of injury.

Facebook went mad and, contrary to the pitchforks and torches crowd that wanted officers to intervene, I support their decision.

This bear has sustained an injury. Darting it and capturing it would likely mean that it would never see its wilderness home again. Nature is not always pretty. This bear may heal, or not. I support AEP’s decision to let it have the opportunity to survive or pass on while living free on the landscape.

The bottom line is that food stress is the greatest indicator of bear-human conflict. If we can reduce the food stress, and/or reduce the attractiveness to our communities in times of food stress, then we can hopefully reduce the number of bears that are removed from the landscape.

Communities in the Rockies are doing the right thing in reducing the number of fruit trees in order to reduce the attractiveness of our townsites to bears.

We are so ahead of the game on a national scale. Eastern Canada has way more bears destroyed every year. I started my career as a park naturalist in 1982 in a park now known as Sleeping Giant Provincial Park. They still have a garbage dump less than a kilometre from the main campground. Their most recent management plan from 2007 indicates that they will do a “closure plan” to get rid of the dump, but it is still there.

We are lucky to live in an area where bears still roam free on the landscape and are not largely human food conditioned. We need to continue to evolve as communities to help make sure that our grandchildren’s grandchildren can still see wild bears on the landscape around the mountain west.

We still have some battles ahead in Canmore in terms of making sure our wildlife corridors remain viable and that people learn that they simply can’t violate area closures. As Bear 148 taught us all, the bears always pay the price for our neglect.

And with that, it’s time to wrap this episode up. Don’t forget to check out the show notes at www.MountainNaturePodcast.com/ep049 for some photographs from my polar bear trip this year but also for links to additional information and resources.

If you’d like to reach out to me personally, you can hit me up on twitter @wardcameron or drop me a line using the contact link on the website.

Don’t forget that Ward Cameron Enterprises is your source for making the most out of your western Canada experience. If you’re looking for a step-on, snowshoe, or hiking guide, drop me a line at info@wardcameron.com.

And with that, the snow is falling and it’s time to go snowshoeing. I’ll talk to you next week.

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