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015 Rutting Moose, Gravel Rivers, and Mountains 101

In this episode I look at some of the dangers moose need to overcome to survive the annual rut. I also examine new research that looks at the gravel rivers in the Rockies and just how important they are. Finally I look at a new course offered by the University of Calgary on Mountain Ecology.

Story 1 – Rutting Moose

As a wildlife photographer, I’m naturally drawn to natures greatest events, and the fall rut for our hoofed animals provides a great opportunity to see life at its rawest. Most mountain residents are familiar with the elk rut. It begins in late-August as the blood supplying the velvet on the males antlers is cut off and the velvet begins to dry up and hormones begin to flow. The bulls rub the antlers against trees and shrubs to remove the velvet, since this is living tissue, there is also some bleeding while the velvet is being shed. This dried blood is what gives antlers their darkened appearance. A close look at a shed antler will reveal grooves along the surface. These sinuous lines represent the veins and arteries that brought the blood supply to the antlers during the growth phase of the antlers. A big bull elk can see growth rates in the neighbourhood of 1cm (.5 inch) every day – a big bull moose, almost 2 cm or 3/4 inch every day.

Around this same time the larger bulls begin gathering females into discreet herds and excluding other bulls from the area. These dominant bulls are referred to as herd bulls while the smaller bulls hanging around the fringes are known as satellite bulls. These less dominant stags are always on the lookout for a cow that they can steal from the herd bulls collection.

Any satellite bulls that want to challenge the dominant stag will be met with a formidable response. The bulls lower their antlers and attempt to shove their opponent while twisting their heads to knock them off balance. Bulls are often injured in these battles, sometimes fatally.

The moose rut is very different thing to watch. Compared to watching the elk rut, the moose rut is much slower. It feels like a grade 9 high school dance. Since there are fewer animals in the moose population, there may only be a few females, and sometimes an equal number of bulls. They spend a seemingly endless amount of time just standing around. While smaller bulls may test the water, opportunities for them to mate are extremely rare. The herd bulls spend a lot of time sizing each other up, moving in for a sniff of a cow, and then returning to the margins.

A study in Alaska’s Denali National Park found that young bulls sparred constantly. Sparring however, is not battle, it’s more of a prep for the battles that lie in their future. One minute they’re feeding side by side and the next they’re sparring. It’s rarely an aggressive. The intent isn’t to harm but to learn.

Dominant bulls rarely spar. They conserve their energy for real challenges from equally large stags. Long before they actually come into contact with another bull, there will be fair amount of posturing and threat movements. They paw the ground and tear up local shrubs with their antlers, all in an attempt at intimidating their opponent to back down. If this fails, the battles are epic. Their antlers are designed to protect them from injury while inflicting maximum damage on their opponent. Once they their antlers connect, they put all of their weight into the conflict. With big bulls weighing in excess of 700 kg or 1500 pounds, these battles are monumental.

Bulls shove their opponents and twist their heads violently in an attempt to either knock him down, or gore him. It’s not uncommon for a bull to be fatally injured in one of these clashes or – even worse, for both to become inescapably locked together by their antlers. When this happens, both bulls perish from a combination of exhaustion and starvation. Just this week, circled the web showing just such a situation in Alaska. In this case, two big bulls became entangled and must have stumbled into a slough pond. One may have been injured during the battle and as he perished, dragged his rival down into the water with him. When they were discovered, they were frozen into the ice with just their antlers and one side of their carcass sticking out above the frozen surface. It was a surreal situation. You can see the images from Alaska here: Moose Perish with Antlers Locked

About 10 years ago, the Lake Louise Visitor Centre had a pair of moose skulls on display that were found hopelessly locked together after having perished in that position. This also happens to elk, mule and white-tail deer as well. YouTube is full of videos of people rescuing entangled stags by sawing off their antlers. For two trophy stags, this is a terrible way to end their reigns.

For victorious bulls, they quickly escort the loser out of the area. While these battles are incredibly violent, they serve an important purpose. It is nature’s way of making sure that the fittest animals have the best opportunity to mate. In the Alaska study, the big males accounted for 88% of the mating while young bulls achieved less than a 2% success rate.

Moose put everything they have into the rut. During the rut, dominant bulls have little time feed and expend all of their summer reserves in an attempt to earn the right to mate. This means that, once the rut is over, they will enter the long winter in poor condition…and unfortunately, once they have mated, they become irrelevant. Their chance of surviving the winter is significantly lower than younger bulls who did invest so much into the rut. These smaller stages kept their summer fat reserves to help them through the cold months ahead. In time, they’ll be the dominant bulls and it’ll be their turn to put it all on the line for the chance to mate. In the meantime, they have a better chance of emerging from the winter healthy

Story 2 – Gravel Bed Rivers

Take a close look at any of our Rocky Mountain streams and you’ll see a very distinctive gravel  bottom. Personally, I never really thought much about it, but for Dr. Richard Hauer, a professor at the University of Montana, these stream beds have revealed an incredible biodiversity that may be key to much of the biological diversity of the Rocky Mountain ecosystems. Say what? These barren, rocky river bottoms are the key to much of the diversity of life in the Rockies? Dr Hauer’s work offers a glimpse into our landscape and one of the most areas most vulnerable human disturbance.

First of all, we should try to get an understanding of the actual geography of Rocky Mountain’s river valleys. Riparian habitats are those areas directly adjacent to rivers and have long been known to be a hotspot for birds, plants and wildlife. As we look around the mountain landscape, we are amazed at the expansive wideness of our glaciated river valleys. These broad u-shaped valleys, carved by the glaciers and then inherited by the rivers left behind have created a truly unique hotbed of biodiversity.

One of the most important aspects of this story has to do with the constantly changing patterns of rivers and streams in the mountain landscape. While some streams are constrained by rock channels, most of our mountain streams are in constant movement back and forth across the valley bottom. Swift water flowing around the outsides of river bends will cut into the bank, eroding away the shoreline. These sediments are then deposited along slower areas of the river. For millennia, our streams have been migrating back and forth across the valley bottom, constantly eroding one area and depositing in another, essentially erasing one area and renewing a new one. This cut and fill process of change is distinctive of the gravel bed river systems that characterize the Rockies.

Runoff constantly varies with the season. Occasional floods surge over the riverbanks, while also renovating the channels in dramatic ways. Anyone in the Bow Valley in 2013 can attest to the dramatic changes that massive floods can have on the landscape. This particular flood redesigned much of the geography of the Bow River and adjacent valleys.

We need to imagine a river moving back and forth across and entire valley over thousands of years, and constantly changing, eroding here, depositing there but never staying the same. If you were to look beneath the water of the river channel and the vegetation stretching across the valley bottom, you would also see a mosaic of sediments including cobbles, gravels and finer sediments.

At the same time, this wide floodplain shows a landscape in varying levels of successional change. A quick examination will show flowing rivers, ponds, old and new channels, dry gravel beds, and vegetation varying from tiny mountain avens flowers to aspen forests and finally to old growth spruce. It is a constantly changing continuum of renovation and rebirth.

Beneath this gravel is a hidden world of water flows. While our visual perception focuses on the actual river channel, the water from that river also percolates across the entire gravel basin, from one side of the valley to the other – perhaps a kilometre or more across. No longer can we look at a river as a discrete entity.  Rather it is a series of veins that are part of a circulatory system of water flowing through the gravels bringing water, nutrients, minerals and life throughout the entire valley. In a single day, water can move several hundred metres across the valley bottom, all hidden within the gravel that hides beneath the forests at the base of the valley.

As water warms due to summer sun, cool water wells up from the underlying gravels creating a wide variety of water temperatures within the river and the adjoining floodplain. In the winter, as surface temperatures cool, warmer water rises from the gravels and helps prevent the river from freezing.

Once we can visualize water moving across the entire valley bottom, we can also envision it bringing with it nutrients and minerals. These, in turn, support a huge assortment of microbes, crustaceans and insects. In fact there is far more diversity of habitats across the valley bottom as compared to the actual river channel. As water moves further from the river channel, microbes help to decompose the organic material carried within the water. These microbes deplete the oxygen in the water and release carbon dioxide, nitrogen and phosphorous.

Where these mineral rich waters emerge, algae blooms thrive, providing food for many different types of insects. At the same time tiny crustaceans and other aquatic insects may spend a portion of their life cycle within these gravel layers, well protected by the overlying layers of gravel. The flowing water cycles nutrients and organic material to them as it flows through the gravel.

Eventually, many of these tiny creatures make their way back into the river to reproduce. When  they do, they become a an integral part of the diet of fish, birds, amphibians and animals. For our native bull and cutthroat trout, survival depends upon these gravel bottom landscapes. The flow of warm and cold water through the gravel also keeps the water cold in the summer and unfrozen in the winter months.

Young trout take advantage of slow flowing tributaries and eddies and will also use the trunks of trees and other debris that has fallen into the river for shelter and protection. Tall trees lining the river also spread their branches wide to offer shade to the young trout as well.

Aspen and poplar forests also rely on the barren gravel floodplains nearer to the water’s edge to become established. They do not compete well with other trees and their seeds only have a few weeks to become established. Seeds are also carried on the wind and in the river’s current to be deposited and eventually to colonize new areas deposited by flowing water.

Further from the water’s edge, spruce and pine forests will gradually replace the aspen forests over time. Some 60% of the plants that call the mountains home can be found in this floodplain zone. Many of these plants are what we biologists call pioneer species. These plants thrive in barren gravel flats where other plants have not been able to plant a tenuous root hold. They tolerate regular flooding but may not play well with others. New river deposits are perfect place for the tiny yellow mountain avens. These nodding yellow flowers carpet these dry gravel washes and create a great habitat for aspen and poplar trees to colonize.

Birds also benefit from these unique habitats. Some 70%, of our local birds rely on the river corridors for part, if not all of their yearly home. Sure, some birds simply hang around the river channels, others expand their presence across the entirety of the valley. Some may just use the area briefly during seasonal migrations.

Our understanding that the river extends completely across the valley bottom is completely new while our plants, animals and birds have taken advantage of this for millennia.

For our larger animals, these habitats are home. Most of us expect to see beaver, moose and otters near water sources, but elk, bison, mule and whitetail deer, as well as black and grizzly bears also take advantage of this habitat.

These floodplains are the first place new shoots emerge in spring so animals that depend on early season plants will also migrate to these same locations. In turn, animals like wolves, grizzly bears, and cougars that prey upon these larger game animals will also follow their dinner to these low valley habitats. In winters, some 40% of wolf kills in Banff National Park were found within these gravel river floodplains. Come spring, when these hoofed animals are weakened by long winters with poor food supplies, but are also attracted to the early growth, the predators are their waiting for them. Wolves will den up in these areas, waiting for the spring migration to attract elk, deer and moose.

Grizzly bears are also attracted to these habitats for other unique reasons. Plants like buffaloberry, the single most important plant for black and grizzly bears in the central Rockies, grow best in these habitats and so we can expect to see far more bears in these areas during the berry season than at higher elevations.

Now for the bad news. One of the challenges of being people is that we love to build our communities at crossroads. We look for places where rivers meet, or where rivers meet a large body of water or an ocean. We build cities and townsites smack dab in the middle of these critical gravel bottom ecosystems. In addition, we often look at these areas of the river valleys as places to be tamed. In towns like Canmore, Banff, Bragg Creek and High River, millions of dollars have been spent since the 2013 floods to make sure that the rivers could never again change their course.

Unfortunately, the entire ecology around us has been built by 10,000 or more years of exactly that…rivers changing, migrating, eroding and depositing. It’s the change that is the dynamic lifeblood of the river valley ecosystem. For animals like grizzly bears, that are very susceptible to human disturbance, this focus on their key habitat patches serves to dissect their travel corridors and prevent movement. When we talk about grizzlies, it’s all about girl power. The ability of females to move freely is a critical aspect of sustaining strong populations. In an area that has become fragmented by human development, the arrival of a female bear can add vitality and new hope to a dwindling population. At the same time, females are also more wary and less likely to spend time wandering through increasing human development.

At one time, grizzlies ranged all the way south to California. As more and more people invaded the landscape, the bear populations found themselves cut off from one another.  Every time populations were reduced to tiny islands, the bears disappeared. In many cases, while the males are a little more tolerant of development, it’s the female’s ability to disperse that makes all the difference in terms of maintaining viable populations over the long term. As the cubs of a female grizzly disperse, they don’t just leave. They tend to simply look for a place nearby so they can develop a range that overlaps that of their mother. She doesn’t just give them a cheeseburger and a road map, rather she remains a part of their lives.

Unfortunately for the animals that rely on these floodplain valleys, many, if not most, are privately owned and very prone to modification and development. We people tend to be the places we armour the banks to prevent the natural processes of erosion and deposition, we build dams and reservoirs, and…oh yah, housing developments, roads and highways.

When we look beyond the apparent barrenness of eroded river valleys and understand that the river is the artery that nourishes the entire valley, we also need to change our interaction with it. The entire valley contains more than double the diversity of insects and invertebrates than that limited to the physical river itself. Our trout spawn exclusively where the mixture of groundwater and gravel bottoms provide the perfect conditions for laying eggs. Even though this area represents only 3% of the landscape, it contains more than 70% of the regions birds and most of our large game animals.

Dr Hauer and his colleagues work is helping us to realize that the floodplains are the most endangered land forms on the planet. As rich as they are, most of their magic has remained hidden from view and as a result they have been colonized, diverted, dammed, drained and rip wrapped. We put so much effort into controlling and harnessing the water that we forget that there is much more going on beneath and adjacent to the river than the tiny ribbon of water can reveal.

Story 3 – Mountains 101

I make my living helping people to understand the natural and human history of Canada’s western mountains. I’ve spend the last 30 years trying to get a handle on the formation of the mountains, their gradual sculpting and evolution, as well as the ecosystems and individuals that call them home. If there is one thing I’ve learned is that I can never stop trying to learn more. The science I learned when I first arrived is no longer the science by which we make decisions today. Our understanding is constantly evolving and as a guide, I need to try to stay on top of the curve.

If you’re like me, and want to get a really good grounding in mountain landscapes, geomorphology and ecology then do I have a deal for you. The University of Alberta has just announced an new FREE course called Mountains 101. it is a 12 lesson course for home study and the cost to audit the course for those of us looking for the knowledge but not a certificate is well – free. The course covers the entire spectrum from the formation of the mountains, the ecosystems that have been built upon that foundation and the ecology surrounding the mountain landscapes.

Zac Robinson, who is an associate professor with the faculty of physical education and David Hic, an ecologist with the biology department came up with the idea. They realized that to get a true understanding of the mountain landscape would require a multi-disciplinary approach. It would involve combining geology, geomorphology, Climatology, Ecology, Biology and even an understanding of human history and recreation.

After creating an undergraduate course, the university asked if they wanted to develop a course that would be open to the public. The answer was a resounding yes and they embarked towards creating an entirely new type of course. The goal was to immerse students into the mountain landscape by using a documentary style along with green screen technology and actual footage taken from the field.

Since the course is free to audit, you don’t have any deadlines or assignments to complete, all you need to do is watch the video presentations at your own pace and gain whatever information that you find useful.

The course also includes experts from Parks Canada, the Alpine Club of Canada and other organizations. It’s a treat to find an academic program that reaches out to organizations beyond the academic sphere.

As a guide and mountain professional, my certificate requires me and other guides to do ongoing continuing education. Simply producing this podcast requires many times the amount of research required to fulfill this requirement but this course is one that EVERY guide, as well as every lover of mountain landscapes, should sign up for. The course begins on January 9 and immediately, all of the episodes will be available to you. Think of it as the Netflix of mountain education…you can binge watch the entire course, or if you prefer, take as long as you would like to work your way through the episodes.

What’s truly exciting about this course is that it represents a new approach to education by universities. The U of C should be commended for creating an academic program and then making a commitment to not only make it available to everyone, but to do so free of charge…well sort of. After each episode, you will need to fill in a quiz before continuing on to the next lesson.

If you miss this course, it will be offered again in May, as well as in the fall. There are no downsides to this opportunity. The course is FREE. There are no commitments as to schedule, and the worst that can happen is that you learn a little more about the landscapes and ecology of mountain landscapes.

If you’re interested in checking out the course, just point your browser to I for one, am looking forward to it.

With that it’s time to wrap up this episode. Thank you so much for sharing your time with me and I hope we can continue to share our stories with you, and with your friends. Why not take the time to share this podcast with at least one friend over the next few weeks. If we all did that, we could double our listernership in a very short time. Also, if you have an idea for a story that you’d like to hear, please drop me a line using the contact link on this site, or hit me up on twitter @wardcameron. You can also leave a comment on our facebook page at We love to hear from you and we’re always looking for new ideas for stories for the show.

I appreciate any feedback that I receive as this program is only as good as it is able to fulfill the goals of people like you – its listeners. If you haven’t yet subscribed, please be sure to do so. All you need to do is click the large “Subscribe” button at the top of this post. Once you click subscribe, every new episode will magically appear on your device ready for you to enjoy whenever you listen to podcast episodes.

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