Legends of the fall
For everything, there is a reason
WINNIPEG’S Portage and Main is famously known as one of the coldest corners on Earth when winter rolls around. But fall holds a special charm on the prairies no matter who shivers at that cold intersection a month or two from now. Here are a few of the things that mark the season in the natural world in Manitoba. Autumn in Churchill is pretty magical, said Douglas Clark, an assistant professor at the University of Saskatchewan School of Environment and Sustainability and former chief warden of Wapusk National Park near Churchill. “It happens early. The bugs die, the tundra plants turn the most amazing colours — red, gold, orange. Geese flock up and head south. Caribou have bright white ruffs of fur around their necks and the bulls gather their harems. Polar bears look unusually vivid against that coloured backdrop, and the light is so clear that when the sun is behind them their fur looks like a golden halo around their entire body,” the polar bear expert said. “Once the ponds freeze up, which will probably happen in a few weeks, the bears start to move around more, and that’s when ‘bear season’ really gets active up there. That’s in terms of both people and bears. The weather is up and down, but getting steadily worse, the bears are all over, and then one day — you never really know in advance when — there’s ice on the bay and the bears are gone. It happens amazingly fast. Within a week, Churchill goes from jam packed to empty and everyone left settles into winter.” While southern Manitoba can’t rival eastern Canada and the Maritimes with their milder fall weather and sheer variety of colour in changing leaves — the palette here is rich in orange, gold and yellow — there’s no question the leaves are the biggest show around from The Pas to Steinbach. “That’s the big thing, changing colours,” said Bruce Ford, biological science professor and curator of the University of Manitoba’s Herbarium. Basically, leaves change colour because of changes in their pigment in response to cooling temperatures. “Leaves on trees contain three main pigments, carotenoids, anthocyanins and chlorophyll. When it gets cold, nutrients cause the chlorophyll to disintegrate and that allows the other pigments to shine through. They’re always there but you just don’t see them,” Ford said.
The orange and the yellow are carotenoids, the same stuff that makes carrots orange. Red is from anthocyanins, a chemical that stores sugar in plants, he said. Ford believes leaves in colder climates like ours probably show more orange and yellow because their leaves contain a higher concentration of carotenoids compared to the red sugar stuff. Most birds head south in the fall. Owls, don’t, but they have a peculiar link with the season through centuries of superstitions about Halloween. Because they’re nocturnal, owls were traditionally associated with witches and magic. Halloween is rooted in the pagan festival Samhain and those ties still bind centuries on into the Christian era. Nicole Koper, associate professor at the University of Manitoba’s Natural Resources Institute, said the main thing birds do in the fall is fly thousands of kilometres to warmer climates but it’s not all they do. “Obviously the migration is the main one. Songbirds will lose up to half their body weight so you can imagine how much they have to eat, they have to stuff themselves to make the journey south,” Koper said. One of the other things some songbirds do in autumn is check out nesting grounds for next year. To do that, they’ll listen for other bird songs. For some birds, if they sing in the fall, it means they were successful that summer. So where they are, that’s a good patch to rear young. Listeners and singers both remember that patch for next year. “That’s particularly important for hatchlings from this year because they have no experience nesting,” Koper said. So if you hear birds singing a lot, they’re bragging about the hatchlings they raised and the other birds that hear them are lining up the same patch of ground, bush or tree to nab it next year for themselves. Smaller birds are more sensitive to cold but the larger raptors, such as bald eagles, will stay around longer. “You’ll see a lot of bald eagles now, heading out in groups,” said Koper. She reported two juveniles flying with two mature bald eagles a few days ago and figured it was a family heading south. Not all birds fly south. Chickadees will stay all winter as will house sparrows and white-breasted nuthatches. “Everybody else has left so they spread out and eat whatever.... That’s a risk, to stay here, but they fluff up their feathers and cross their fingers!” Moose, elk and deer are caught up in mating rituals for the annual rut and bears take a berth for winter, heading to their dens to sleep out the cold.
Autumn foliage frames a horse munching grass in a field east of Libau. Background, Autumn leaves are reflected in a creek near Virden.