It's harvest time here in the Yukon, at the northern edge of the boreal forest. The leaves on the aspen trees are beginning to turn sunshine-yellow, the fireweed is crimson, and the high alpine bushes are showing red. People are out in the bush every weekend, picking berries and gathering mushrooms.So, I might add, are the bears, so the wise human berry-picker makes plenty of noise!
The forest here can look pretty sparse -- spindly trees and a forest floor covered with tiny plants, mosses, and lichens. You'd think that by the time the big two-footers and four-footers were done harvesting, there wouldn't be much left for anyone else.
But you'd be wrong. A lot of little creatures depend on the foods provided by the boreal forest to make it through the long winter, and they're out harvesting too. If you look closely at the tiny plants that flourish beneath the trees and along the forest's edge, you'll find plenty of goodies to gather.In the alpine, where forest gradually gives way to alpine tundra, pikas are building up their haystacks. A small cousin of rabbits, a pika can stash away 20 kilograms of grasses, leaves, seeds, and flowers over the summer, much of it in large piles just outside the entrance to its burrow. When the winter wind whips across the bare mountainside, driving snow before it, a pika doesn't have to go far for a snack.
Down on the forest floor, the voles are also tucking away winter groceries. They're less ambitious than pikas, and a lot smaller -- like tiny, delicate mice. Still, a single northern red-backed vole might store up to 3 kilograms of seeds, berries, and fungi near its winter burrow.But voles and many other creatures of the forest floor don't just depend on food hoards all winter. When snow covers all that autumn bounty and the forest looks barren, many of the forest's smallest creatures are still out there, awake and busy.
They scurry around all winter under the snow, in an area called the subnivean zone where the warmth of the ground partially melts the snow above it. There, tiny animals search the buried vegetation or scoot through tunnels in the snow above, still harvesting frozen blueberries, bearberries, cranberries, rosehips, seeds, kinnikinnick berries, fungi, and all the other tiny jewels of the boreal forest's treasure chest.If you'd like to know more about what people and animals are harvesting in the Yukon forest, Jozien has a blog called Yukon Wild Berries.
To find out more about the physics of the subnivean world, the Cable Natural History Museum of Wisconsin has a nice online article about Subnivean Temperatures.
And here's a nice article in the St. Albert Gazette (Alberta) about subnivean life a little farther south in the boreal forest.
Or you can check out the chapter about life in the cold -- "Ice is Nice" -- in my book Lizards in the Sky: Animals Where You Least Expect Them.
Best of all, go for a walk in the autumn woods, with your local guidebook and a berry bucket. Happy harvest!
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This summer, as a volunteer assistant, I joined a biology project. A friend in
Amy Groesbach took these photos. To see lots of pictures of how she and her mentors investigate traditional First Nations clam gardens, go to
And here's Amy holding one of the squares she made out of 1-inch PVC tubing, so we could dig holes exactly 25 cm across. We had to dig them 30 cm deep, which is exactly the length from my elbow to my knuckles. In a few beaches, there were experiments placed where Amy buried hand-made mesh bags holding living clams, and retreived them later.
I learned how to make a sampling device. A kitchen scrubber called a Tuffy was attached to a ten-inch piece of rebar with a cable tie. Easy as pie. After the rebar was pounded into a clam garden, the Tuffy would collect clam spat. Intertidal biologists have been inventing devices to collect clam spat. Someone tried using kitchen scrubbers, and found the Tuffy brand was particularly effective. The fun part is pounding the rebar into the garden, when the pounding has to be done underwater. Smack! Smack! into the water. "Science! Doing it all for science!" Spit out muddy sea water. "I'm still having fun!"
The first time we catalogued clams, both living clams and the shells of dead clams, our group gathered under the tarp over our kitchen area. Seated on five-gallon pails, we hunched over our shells. A rain squall fell around us, and we got chilled and stiff before we were done and dinner could be made.
The second time was a sunny afternoon, so after lunch on a rocky slope below a midden across the bay from camp, we set up the calipers and notebooks. Each of us moved into the shade or sunshine at will. Our postures were not hunched this time, but varied from leaning on one elbow like a diner at a Roman feast to laying back against rocky slopes perfectly designed to support our backs and heads. Looking out across the bay was wonderful. I'd always thought that doing science involved wearing lab coats, not bathing suits or my shortie wetsuit. This place was much nicer than a basement lab somewhere.
If you look over a clam garden at high tide, from a boat or from the shore, you probably wouldn't see anything to tell you that this is a place shaped by human gardeners. When the tide is a little lower than full, you might guess at the shallows near shore, usually in a small bay or between two rocky points. But when the tide is low, approaching a zero tide, the clam garden is revealed.
