In this episode, I look at the incredible clouds of pollen that have turned the skies yellow this past week. I also look at how shortening winters is creating new challenges for animals that change colour to match the seasons. Finally, I share a little bit of the Hollywood History of the Rockies
Sulphur Storms
This past week has marked the start of pollen season in the mountain west. The white spruce, in particular, released vast amounts of yellowish-green pollen, coating every car, patio set, pond, and puddle. The railings alongside trails and even the surfaces of leaves have been covered in this fine powder.
On my car, places I previously touched were dusted in a manner similar to fingerprint dust, leaving a yellowish outline of my fingerprint.
Spruce are part of the Pine Family of trees, and all the members of this group reproduce in a similar fashion. Rather than using insects to pollinate the female flowers, they have evolved to use the wind.
When a plant relies on something as random as a mountain breeze, it better produce a lot of pollen, and this past week we saw massive sulphur storms with clouds of yellowish pollen streaming from the trees and, in some cases, entire forests were blurred in a yellowish fog as the pollen spread its way across the landscape.
Members of the pine family in the central Rockies include the white and Engelmann spruce, lodgepole, limber, and whitebark pines, Douglas-fir, subalpine fir, and the alpine larch.
Every tree contains both the male and female cones with each taking a different role in the reproductive process.
Male cones form on the lower branches while the female cones grow higher up. The male pollen cones grow at the base of the current year’s new shoots in early spring, which in this part of the mountains is usually around the latter part of May.
Different species produce different numbers of male cones, with a range between 15 and 140. Once the pollen has been dispersed by the wind, the male cones fall off the tree.
Each male cone is a smooth, oval structure that contains dozens of spore-producing bodies called microsporophylls. When the cone is ripe, it releases tremendous numbers of tiny pollen spores.
Each of these spores sport two tiny wings called sacci that help it stay airborne. When the sky turns yellow with this pollen, it’s often referred to as a sulphur shower.
Conversely, female cones grow very slowly and usually take several years to mature. This leaves cones in differing stages of maturation on the same branch with newer cones forming towards the tips.
A first-year cone is soft and small, usually just a centimetre or two in size. Its main job is to collect the pollen and fertilize the cone.
Second-year cones are much larger in size, more woody, but still green in colour.
By the third year, the cones are hard and have turned brown and now contain fully-formed seeds ready for germination.
Female cones are also much larger than their short-lived male counterparts. The cones form in either pairs or clusters along the branch and they vary dramatically in size. Lodgepole pine cones are only around 5 cm long, while the cones of limber pine can exceed 20 cm in length.
Each cone is made up of alternating bracts and ovule-bearing scales. These scales accept the pollen and transform into winged seeds as the cone matures.
Wind pollination is an ancient strategy and was utilized by the earliest of plants. It was the go-to strategy used by plants some 125 million years before flowering plants began to conscript insects to transport their pollen to other flowers. Even this was still 50 million years before the Cretaceous, the age of the dinosaurs, arrived.
Almost all land-based non-flowering plants employ wind as their primary method of passing pollen from male cones to the ovaries hidden with the ovules of female cones.
The randomness of wind as a transport mechanism means that if a grain of pollen lands on just the right spot, the female ovule needs to have some way to catch it before it blows away,
They do this with a pollen droplet. This is a sugar-rich droplet exuded from the top of the ovule with the sole purpose of giving pollen grains a sticky surface to land on.
For the pollen to maximize its airborne flight, it has to be extremely light. To do this, it’s heavily dehydrated before it’s released. When it lands, it needs water and nutrition in the form of sugars and proteins to help it develop further in preparation for pollination. The droplet offers just what a dehydrated pollen grain needs.
There is some evidence that prior to the development of flowering plants that some insects adapted to seeking out these sugary pollen droplets. It may have been this attraction that prompted further diversification in plants to develop nectar-producing flowers. Some of the more ancient plant families, like the pines, continued to rely on wind for their pollination despite the success of insect-pollinated flowers.
As you marvel at the amazing clouds of pollen released this year, while at the same time cursing the fact that every outdoor surface is covered with it, know that it is part of an age-old strategy that maintains the world’s most ancient trees.
Mismatching Colours
Whenever any bright-eyed university student begins to study ecology, they’re quickly introduced to the pepper moths of Manchester, England. These common moths can be found in two different forms, a lighter more salt and pepper-coloured variety as well as a sooty, almost black variety.
Prior to the industrial revolution, the darker variety was unknown. It was only first described until 1811. A dark moth on a light tree meant that it was far more likely to be spotted by hungry birds and so they are estimated to have represented only 0.01% of the population.
These light moths almost exclusively occupied their range in 1760 when England’s industrial revolution first began to darken the skies with the soot from endless coal fires. Increasingly, in industrial towns like Manchester, surfaces of buildings and trees began to reflect this sooty character and gradually darkened in colour.
By 1811 when the first dark variety of pepper moth was discovered, Manchester was beginning to look pretty dismal and dark with coal dust staining many of the trees. Coincidentally, pepper moths used those same trees to hide from predators.
For centuries, the light-coloured pepper moths could perch on the bark of trees and effectively disappear into the patterns of the tree’s bark. As these same trees became increasingly darkened by coal dust, the moths began to lose their camouflage. Prey that can’t hide, attracts predators and the light-coloured moths increasingly became the meals of hungry birds.
That was when something very interesting happened. A dark, sooty variety first made its appearance. Its dark appearance gave it a distinct advantage over the lighter variety, and by the end of the 1800s, industrial towns like Manchester and London were dominated by these dark varieties. By 1895 the dark variety had risen from 0.01% of the population in 1760 to 98%, eclipsing the more vulnerable light pepper moth variety.
Why am I wandering down this ecological memory lane? Because the same situation is happening around us right now, not due to soot pollution, but rather human-caused changes to the climate. The mountain west is home to a large number of animals that take advantage of the seasonal changes by turning white to help them vanish into winter landscapes.
These seasonal colour changes occur in a number of animals and birds including the willow and white-tailed ptarmigan; least, long-tailed and short-tailed weasel; and the snowshoe hare.
These adaptations to the annual cycle of winter snows and summer foliage have evolved to maximize their camouflage throughout the year. Predator and prey alike have evolved similar strategies to help them to stay hidden. While weasels are voracious predators, they’re also on the menus of other, larger predators. The same pressures that forced snowshoe hares and ptarmigan to change colours, also affect them.
Changing your colour to take advantage of seasonal camouflage only works when the camouflage matches the season. Since historic weather trends varied only slightly from one year to the next, the timing of colour change for most of these diverse species was largely tied to the length of daylight in spring and fall. While in the past it may mean that a snowshoe hare, ptarmigan, or weasel might have a short period of mismatched colour, the majority of their season was ideally suited to the prevailing background colours.
Brown weasels and hares, along with mottled ptarmigan, simply disappear in the summer landscapes of the Rockies while white animals offer similar protection in snow-covered landscapes.
Many times I’ve been scared to death while cross-country skiing when a covey of ptarmigan, also called an “invisibleness” of ptarmigan, suddenly flush at your feet. These tiny grouse-like birds allow themselves to be completely buried by snow for warmth, only flushing when you’re almost on top of them. A quiet cross-country ski is suddenly interrupted by an explosion of feathers.
Changing climates is wreaking havoc on many of these animals. A white ptarmigan against a snowless alpine meadow is just as dangerous as brown snowshoe hare against a snowy forest. If your colouration is in stark contrast to your environment, you are also far more visible to potential predators.
Climate change is causing many challenges to plants, animals, and birds in the north country. Warming climates can cause mismatches in reproduction schedules, emergence from winter hibernation, migration, and even connection to key food sources.
If a bird’s migration is timed to allow it to nest just as certain insects emerge in the spring – and then those insects emerge several weeks earlier – than the bird’s reproductive success is put at jeopardy. So many of nature’s key events are timed to historically predictable connected events. Animals give birth when the maximum amount of food should be available. Birds migrate at the right time to take advantage of seasonal foods in their winter and summer ranges. Animals emerge from hibernation when new foods should be available to help them regain strength after a long winter sleep.
Just like the colour change schedule of animals, if the schedule changes then how flexible are the animals in their response to this change? So many annual cycles are hard-wired into plants and animals that their ability to respond to rapid changes can be very limited.
Back in episode 42, I talked about a discovery in Alaska where bears were choosing elderberries over salmon for the first time. Historically the berries ripened after the salmon run and offered grizzlies a nutritious food after a long period of feeding on salmon. With warming climates, the berries are now ripening at the same time the salmon are running. The bears have to choose one food and they picked the berries. This means they no longer have the same feeding period over the summer months. No longer do they have a long period of feeding on salmon, followed by time to munch down on elderberries. The foods are now out of sync with the bears historical feeding schedule.
When all of these evolutionary behaviours emerged, climates were, more or less, relatively stable. Days with snow varied year after year within a reasonable margin of error. When the climate changes so fast that winter arrives later and later, and spring arrives earlier than unless the animals can respond quick enough they’ll find themselves with a contrasting coat that makes them far more visible to their predators.
Like the moths in 19th century England, they can’t count on their colouration to help hide them from hungry hunters.
These colour mismatches have prompted numerous studies to look at how individual species are able to respond to these rapid changes. A 2012 study looking at snowshoe hares looked at their response to fewer snow-covered days each year. It found that since the colour change of hares is most likely connected to the length of day, their vulnerability to shorter winters would be a factor of their flexibility to alter the timing of their autumn and spring moults where they grow a coat of a different colour. Any hare that is white when the landscape is not, has a target on their back. Conversely, a brown hare is in danger against a snowy backdrop.
Populations of snowshoe hares, more so than most animals are absolutely tied to their level of predation. Lynx evolved to eat snowshoe hares almost exclusively while many other animals will also take a hare whenever possible. The simple fact that they were born delicious means they’re on the menu of any carnivore lucky enough to see past their camouflage.
In the mountain west, the population of hares rises and falls in concert with predation from lynx. As the hare population rises, lynx produce more kittens which means they need more hares. As lynx increase their predation on hares, the hare population drops. Fewer hares result in a subsequent drop in lynx numbers. These two animals are connected like few others.
For an animal that lives and dies by its ability to hide, having the right match between colour and landscape provides huge advantages to appropriately coloured individuals. This means that, as climate changes, those hares who’s pelts allow them to best hide will have the optimum opportunity to survive and, subsequently, pass those adaptations on to their young.
This study looked at the hare’s ability to vary its colour phase based on changing climate realities. If individual hares are able to adjust to rapidly changing seasonal realities than those changes would be quickly passed on through the population. This study found that the fall moult which turned their coat to white had little flexibility in terms of timing. This meant it was likely hard-wired to its connection to the length of daylight. The spring moult though showed some signs of adaptation with a slight ability to slow or increase colour change based on local conditions.
Ptarmigan are in a particularly dangerous situation in the mountain west. Not only are climates warming, but these birds are specialized to live at the very highest elevations. As climates continue to warm, conditions will likely see them forced up higher and higher up the mountain until they literally run out of habitat.
Ptarmigan are also experiencing a similar mismatch between seasonal colour. While physiology can take too long to adapt to rapid changes in their environment, out of season white ptarmigan are known to work to soil their feathers after breeding to try to minimize their contrast to the background landscape.
Many weasels are experiencing similar challenges. Recent studies of the smallest predator in the country, the least weasel, have found that it’s also finding itself moving from predator to prey due to its unexpected visibility caused by lack of snow. Almost all predators are also prey to larger animals and for this diminutive weasel, being visible means potentially being someone’s dinner.
In a Polish study looking two varieties of least weasel, one that changes colour during the winter and one that doesn’t, it shows that climate change, like the moths of England, is showing rapid changes to populations.
In many colour changing animals, there are usually individuals who don’t change colour. In northern climates, this usually means that the brown weasels have a lower chance of survival during snowy months.
For many weasels, predation from largely, birds of prey, can be the highest cause of mortality in a particular year. Like the moth study in England, this study found that camouflage was the most important factor determining predator detection in weasels.
As climate changes and winter snows dwindle, weasels may find that white winter weasels are more heavily predated than weasels that don’t change colour. Southern brown populations will likely shift north as white weasels find themselves falling to the talons of hawks.
Changing climates are changing everything. The news stories often talk about what WILL happen with changing climates but the changes are happening right before our eyes.
Last fall I watched a red fox kill an arctic fox near Churchill Manitoba while working as a polar bear viewing guide. The red fox has migrated north and arctic fox are very vulnerable to invasive predators.
Alpine animals like ptarmigan and pikas are being forced higher and higher up the mountains until they simply run out of mountain. This makes them some of our most vulnerable animals.
The role of seasonal colour change will evolve over the next 50-100 years. Animals that are out of phase with the season will find themselves increasingly on the menu. Behavioural adaptations, like the ptarmigan soiling its white plumage, may help, but we may also see populations migrating, changing, and disappearing depending on each animals ability to react to unprecedented rates of change.
For now, marvel at every sighting of ptarmigan, hare, and weasel. They’re dealing with intense climate challenges and only time will tell how they succeed to changes, not of their making.
Next up…Hollywood North
Hollywood North
The mountain west has long been the backdrop behind many successful movies. I get a kick out of the fact that the first silent movie filmed in the Rockies was called Cameron of the Royal Mounted, and Cameron is my last name.
In this early film, a Scottish immigrant becomes a member of the Mounties only to be accused of forgery. To clear his name, he had to capture a gang of train robbers and stop a band of rogue natives.
Yup, this is about as unlikely a story as you could imagine in Canada. However Hollywood fell in love with the landscape – not to mention the exchange rate on the dollar – and Hollywood has been returning every year since.
Movies like Son of Lassie filmed in 1944 and Emperor Waltz in 1948. 1953 was a big year. That year Jimmy Stuart filmed the Far Country, Shelly Winters and Alan Ladd filed a movie called Saskatchewan…in Alberta, Howard Keel and Ann Blyth did a remake of the classic film Rose Marie, and Marilyn Monroe almost died on the Bow Falls in the town of Banff during the filming of The River of No Return.
If you watch the movie, the characters portrayed by Marilyn Monroe and Robert Mitchem are fleeing from a group of renegade natives by taking a raft down the Bow River. While the movie is ostensibly set in the middle of nowhere Montana or Wyoming, it was filmed in and around the communities of Banff and Jasper.
One of the pivotal scenes in the movie has them rafting over the Bow Falls while a hail of arrows falls around them from the cliffs above. Since movie effects weren’t as advanced as they are today, it’s pretty obvious that it’s two mannequins on the raft but the effect is still a good one.
Even though Marilyn was not actually on the raft, the crew had to do some close-ups of her near the actual falls so they could see the look of terror in her eyes. Unfortunately, while she was posing, she fell and almost did go over the falls. In the end, she was lucky to limp away with just a broken ankle. After this point, the bell staff at the Banff Springs Hotel got to draw lots to see who would get to push Marilyn around in her wheelchair.
A quick google search will turn up numerous photos of Marilyn relaxing around the hotel and golf course with her crutches during filming.
In one of the other classic films of 1953, Howard Keel and Ann Blyth did a remake of the classic Nelson Eddy and Jeanette MacDonald film Rose Marie. One of the biggest tourism myths in the Rockies is that the 1936 film with Eddy and MacDonald was also filmed in this area. At the Maligne Lake Chalet, they even have a canoe nailed to the ceiling with a carved wooden sign claiming to be the original canoe from the movie. Unfortunately, it’s a complete falsehood. Nelson Eddy and Jeanette MacDonald never filmed in Canada. Their scenes were filmed in the Lake Tahoe area of Nevada.
There were some scenes of Mounties training that were filmed in Canada but none of the major scenes was filmed here.
Today, few movies come to Banff and Jasper to film. Scenes like Bow Falls are photographed several million times each year making many of the panoramas simply too recognizable to sell the illusion that they are in Montana or Alaska.
They did continue to use the mountain parks in movies into the 1960’s, including 1965’s Doctor Zhivago. In that movie, one of the classic scenes takes place on the train to Yuriatin, ostensibly in Siberia, but it’s actually filmed in the Spiral Tunnels in Yoho National Park. When the train emerges, a keen observer will recognize the distinctive peak of Cathedral Mountain rising above the valley.
According to the IMDB movie database, this scene used stock footage and none of the actual production was done in Canada. The Wikipedia page does suggest the train scene was actually filmed here with the cast members.
Another long-held myth was that the train station at Lake Louise was used in the movie. That’s completely false, Almost all of the filming took place in Spain and Finland over a 10-month period.
Regardless of whether the actors were actually here, the Spiral Tunnels will live on in one of the most classic films of the 20th century. The film earned 111.7 million dollars in Canada and the U.S. and when adjusted for inflation, ranks it right up there with many of today’s big screen blockbusters.
After Doctor Zhivago, the area around the Stoney Reserve near Morley began to be the focus of film crews. The mountain panorama that includes Mount Yamnuska is a constant presence in some classic films. Films that represent this area include my favourite Dustin Hoffman film, 1970’s Little Big Man, and 1975’s Buffalo Bill and the Indians starring Paul Newman and Burt Lancaster.
Before long, movies began to discover the wider Kananaskis Country landscape and it’s now become one of the most filmed mountain locations in Canada. Films that kicked off the filming in this area include the 1980 film Death Hunt with Lee Marvin and Charles Bronson, and 1988’s Dead Bang with Don Johnson and Penelope Ann Miller. Others include 1993’s The Last of the Dogmen with Tom Berenger, which also included footage of Takakkaw Falls in Yoho National Park and the classic film Legends of the Fall with Anthony Hopkins and Brad Pitt. This movie had locations in Calgary, Morley, and Vancouver.
More recent films have included 2010’s Inception with Leonardo DiCaprio as well as another DiCaprio film, 2015’s The Revenent.
The movies and TV series keep coming back to this amazing landscape. Popular TV shows like Hell on Wheels and Fargo were also filmed in and around Calgary. If you visit the mountain west this year, be sure to study the vistas around you. You may see them in your favourite movies.
And with that, it’s time to wrap this episode up. Don’t forget to check the show notes at www.MountainNaturePodcast.com/ep061. As usual, if you’d like to reach out to me directly, you can comment on the show notes or hit me up on Twitter @wardcameron. And with that said, the sun’s out and it’s time to go hiking.