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Fall Canadian Shield Visit us on the Web at www.ontarionature.org FAMILY NATURE NOTES FALL 2007 Written by Kerry G.Everitt Design & illustrations by JudieShore For generations the rocky outcrops, sparkling blue lakes and dense wilderness forests Hiding inplainsight of the Canadian Shield have shaped our identity as Canadians. Life is not easy on the Canadian Shield. Many species have For more information about adapted to the ever-changing environment by using their the Canadian Shield, check ability to blend into their surroundings, a process known as out thes websites: camouflage. Play this modified game of hide and seek to show • http://www.britannica. the importance to wildlife of blending into the environment. The com/eb/topic-91992/ Canadian Canadian-Shield You will need some small pieces of • Be sure to remember where you paper of different colours (paint chips put all of your pieces! Your partner, • http://encarta.msn.com/ work well), a friend and a natural the seeker, must now be a sleuth encyclopedia_761578439/ Canadian_Shield.html area such as a forest, field or park. and try to find all of your camou- Shield flaged pieces of paper. • http://en.wikipedia.org/ • Cut the paint chips or paper into wiki/Canadian_Shield small squares; two-by-two-cen- • When the seeker has found all the timetre squares work well. Use pieces or has given up, trade Your local library will also have vibrant colours — purples, blues places. The seeker is now the hider. books and articles about the and oranges — as well as “natur- Canadian Shield. • Which pieces were the hardest to al” colours such as greens and S browns. You and your partner will find? Which were the easiest? upplement to ON Nature, 2007 Fall each need at least one sample of Why would it be an advantage each colour, but having two or for an animal to be able to cam- three of each will make the game ouflage itself in its habitat? 201-366 Adelaide St. West, Toronto, even more fun! • If it is a rainy day, you can still ON M5V 1R9, Tel: (416) 444-8419, play the camouflage game inside. 1 800 440-2366, Fax: (416) 444-9866 • One player is the “hider” and the E-mail: [email protected] other is the “seeker”. The hider Try hiding your colour samples in Website: www.ontarionature.org begins by trying to match the the kitchen (no fair hiding them in Copy Editor: Sarah Webber the cupboards), living room or Reviewer: Jimmy Blackwood colour samples to things in the Printing: DTP Inc. natural surroundings. Perhaps there bedroom. are some bright blue wildflowers on which you can place your blue paint chip. Whether you call it the Canadian Shield, exposed rock, large depressions in the sur- the Precambrian Shield or the Laurentian face and very little soil. When tempera- Plateau, this land mass covers nearly half of tures began to rise and the massive glaci- Canada, parts of the northern United States ers melted, water filled these depressions, and nearly all of Greenland. creating the lakes that we can still see The Canadian Shield is part of the today. remains of an ancient and very large vol- The Canadian Shield is rich in miner- canic mountain range. Many people believe als such as iron, nickel, zinc, copper, ura- that it once resembled the present-day nium, silver, gold and platinum. As a Himalayan mountain range in both size and structure. Over result, many thriving mining communities dot the landscape millions of years, water, wind and glaciers shaped the land within this region. into the rolling hills and rocky outcrops that we see today. Because the shield stretches a vast distance from north to Only a very thin layer of soil covers most of the shield’s south, its climate varies depending on location. In the north bedrock. During the last ice age, about 15,000 years ago, the temperatures are cold and the limited amount of soil is advancing glaciers scraped the land. Acting like a giant bull- frozen for long periods. This soil is known as permafrost. The dozer, topsoil and rocks were pushed hundreds or even thou- more southern Hudson Bay region has soggy soil and many sands of kilometres from their original location, leaving wetlands, such as marshes and bogs. The rocky ground and thin soil make painters, such as the famous Group of for poor agriculture on the Canadian Seven, and writers for centuries. Shield, but provide the ideal conditions Vacationers are attracted to the many for a thick coniferous and mixed-wood secluded lakes and rivers — the perfect Aboriginal People Northern goshawk forest, the boreal forest. Spruce, pine, fir spot for cottages and resorts. The Athapaskan or Dene people, such as the Chipewyan, and Algonquians, such and birch trees can be found through- The shield’s unique and varied land- as the Ojibwe, Cree, Naskapi, Ottawa, Algonquin, Innu and Montagnais were out much of the shield. As a result, scape provides ideal habitat for many forestry is one of the largest primary the original inhabitants of the Canadian Shield. different plants and animals. The glacial industries (a primary industry is one lakes and wetlands are home to fish Like the birds and mammals of the forest, many of these people moved to the that is based on natural resource extrac- such as largemouth bass, muskellunge, more southern reaches during the most inhospitable months and travelled in tion) on the shield. The boreal forest of (better known as muskie), sturgeon, search of caribou, moose or other sources of food. Canada is nearly six million square kilo- rock bass and northern pike. Loons, Although food was not always abundant for the Aboriginal people, with a lit- metres in size, approximately the same turtles, salamanders, newts, otters, tle ingenuity they made do with a variety of food from different sources. They size as the Amazon rain forest! muskrats, herons, beavers and moose hunted and speared large mammals such as deer and caribou, and snared smaller One of the largest cities on the are also attracted to the watery mammals such as hares. The Ojibwe built fences of sticks and brush and placed Canadian Shield is Sudbury, habitats found on the shield. them across a stream. These traps allowed water but not large fish to pass Ontario, home of the big The boreal forest provides through. The women would dry and pound the fish meat and mix it with oil. nickel — a nine-metre habitat for wolves, caribou, Winter This nutritious mixture, which stayed fresh for several months, was a winter sta- high replica Canadian bears, deer and numerous ple when food was scarce. nickel. This area is other mammal species, as on the Shield The Iroquois and the Algonquin planted corn and pumpkins, and harvested believed to be the site The winters on the Canadian Shield are well as birds. wild rice, blueberries, choke cherries, sumac and wintergreen in some of the where an asteroid that long, cold and harsh. Many species Unlike many lakes in southern areas of the Canadian Shield, where small pockets of soil occur. crashed to earth nearly have adapted to the changing seasons southern Ontario, those two billion years in unique ways. You probably only eat blueberries in your pancakes or muffins, but young found on the Canadian ago. Nickel, copper Snowshoe hares and ermine use camou- Ojibwe and Cree children also used blueberries for medicinal purposes. The Shield are often crystal clear. The sur- and platinum are the main flage — changing colours to blend into leaves were made into a tea to help cure headaches, and crushed leaves could be rounding granite rock is very hard and minerals found in asteroids, their surroundings — to hide from applied to wounds to help speed healing. does not dissolve easily in water. As a The Boreal and this chance collision has predators. During the warmer months, result, bacteria, algae and plankton can- For travelling in the shield region, which had countless rivers, the Aboriginal made Sudbury one of the these creatures are brown and so are dif- not thrive because of a lack of nutrients, people made canoes made from birch trees. They created a wooden frame from Forest largest nickel producers in the world. ficult to see against a background of making the lakes sparkling clear. the lightweight wood and then stretched birchbark, which is pliable yet strong, Reach into your pocket and pull out a grasses and vegetation. In the winter, Did you know … portions of over the frame. To waterproof the seams between pieces of bark, these people nickel; you are holding “alien” money! Did you know … fossils of bacteria any brown creature would stand out the Canadian Shield formed used either a “glue” they obtained from the bladder of the sturgeon, heated Nature abounds on the shield and and algae that are over two billion against the snow, but then these species nearly 4 billion years ago, which means spruce gum or grease from one of the many mammals they hunted for attracts both adventurers and tourists. years old have been found on the are ghostly white. that it contains some of the world’s food. The result was a lightweight but strong canoe that Its rolling landscape and picturesque Canadian Shield. oldest rocks. To escape the cold, many birds could be hoisted overhead and carried when the lakes and forests have inspired poets, migrate to warmer climates during the rivers were blocked or became unnavigable. If winter. Many boreal mammals, amphib- damaged, the canoe could easily be repaired Northern Pike ians, reptiles and insects hibernate, or using materials readily available in the forest.
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