Life Linked to
Tundra Leader’s Manual Borgir, Nordurslod 600 Akureyri, Iceland +354-­‐462-­‐3350
www.caff.is
www.arcticbiodiversity.is [email protected] @CAFFSecretariat facebook.com/CAFFS Writing, research and design by: Eamer Science & Policy (Claire Eamer, Megan Osmond-­‐Jones, Kelly Badger) www.eamerscience.com Artwork by: Sherrie York www.sherrieyork.com Funding and support provided by CAFF Secretariat and Alcoa Foundation.
ii Contents 1 Introduction ........................................................................................................................................ 1 2 The Tundra .......................................................................................................................................... 2 3 Equipment for Exploring the Tundra ................................................................................................... 6 4 Activities for Individuals and Small Groups ......................................................................................... 8 4.1 LISTEN LIKE AN OWL ..................................................................................................................... 8 4.2 GO SLUG HUNTING ....................................................................................................................... 9 4.3: MAKE A TRADITIONAL STRING HARE ........................................................................................ 10 4.4 EXPLORE TRADITIONAL ECOLOGICAL KNOWLEDGE ................................................................... 11 4.4.1 TRADITIONAL ECOLOGICAL KNOWLEDGE EXTENSION ............................................................ 12 5 Activities for Larger Groups and Classes ........................................................................................... 13 5.1 BUILDING TUNDRA FOOD WEBS ................................................................................................ 13 5.2 FOOD WEB TAG .......................................................................................................................... 15 5.3 WHAT KIND OF TUNDRA IS NEAR YOU? ..................................................................................... 17 Appendix A: Species Information ......................................................................................................... 22 Lichens .............................................................................................................................................. 22 Arctic Willow .................................................................................................................................... 24 Marsh Slug ........................................................................................................................................ 25 Arctic Woolly Bear Caterpillar .......................................................................................................... 26 Lemmings (Brown Lemming and Collared Lemming) ....................................................................... 27 Hares ................................................................................................................................................ 29 Rock ptarmigan ................................................................................................................................ 31 Caribou and Reindeer ....................................................................................................................... 32 Snowy Owl ........................................................................................................................................ 34 Wolf .................................................................................................................................................. 36 Further Information ......................................................................................................................... 37 Appendix B: Activity Sheets .................................................................................................................. 41 Building Tundra Food Webs worksheets .......................................................................................... 41 What Kind of Tundra is Near You? worksheets ................................................................................ 46 iii GLOSSARY tundra The tundra biome is a vast, cold region of Arctic ecosystems characterized by mostly treeless vegetation and and a frozen layer of subsoil. biomes A large community of plants and animals defined by their regional climate and dominant vegetation types. bioclimate A climate and its influence on living organisms. alpine tundra occurs at higher elevations, where summer temperatures stay low enough to discourage trees ecosystem All the living things in an area and the ways they interact with each other and with the non-­‐living world around them primary productivity The rate at which organisms in an ecosystem convert energy from the sun (or chemical energy in some cases) into organic matter. In a tundra ecosystem this is the rate of plant growth. biodiversity Short for biological diversity. It describes the variety of life forms on earth, in a region or in an ecosystem. deciduous Describes trees or shrubs that shed their leaves at the end of the growing season. prostrate Describes a plant that grows close to the ground. endemic Species that are native to a region, and not found elsewhere. thallus The body of an individual lichen, composed of a protective skin of fungal tissue and a photosynthetic layer beneath. substrate The surface on which an organism grows or is attached. biomass Material that originates from living, or previously living organisms. Can be animal or vegetable material, living or in various states of decomposition. catkins An erect or drooping spike of male or female flowers. Usually lacking petals, these are the reproductive structures of many shrubs and trees. gall Growths on the stems, leaves, flowers or roots of plants caused by parasitic fungi, bacteria, insects or plants. iv gastropods Large diverse group of molluscs. Includes terrestrial, marine and freshwater snails, slugs and limpets. ungulates Used to describe all large hoofed mammals. Arctic ungulates include caribou, muskoxen, moose and elk. instars The developmental stages insects go through between each moult until they reach sexual maturity. v 1 Introduction Background to the Project In May 2013, the Conservation of Arctic Flora and Fauna (CAFF), the biodiversity working group of the Arctic Council, released the Arctic Biodiversity Assessment (ABA). The ABA contains the best available science—informed by traditional ecological knowledge—on the status and trends of Arctic biodiversity during a time of rapid social, economic and environmental change. While much of the report is aimed at Arctic policy makers, the information it contains is important to all Arctic residents and to many people outside the Arctic. In order to make that information more easily available, particularly to young people, CAFF is developing a set of educational kits about Arctic ecosystems and Arctic biodiversity. Each kit includes a pocket field guide that can be used on its own or together with additional material available on the CAFF website (www.caff.is). Accompanying each pocket field guide is a Leader's Manual to help teachers, youth groups and community leaders make use of the field guides in their educational programming. For a complete list of available pocket field guides and manuals, and for downloadable and printable versions of them, go to the CAFF website at www.caff.is. Life Linked to Tundra: Pocket Guide and Leader’s Manual This Leader’s Manual and its related pocket field guide look at some of the organisms and processes closely associated with tundra. The pocket guide focuses on a set of plants, animals and other organisms—with brief information about how they fit into an ecosystem. The leader’s manual provides background information about the tundra, the nature of ecosystems and some of the changes and threats that could affect Arctic ecosystems and biodiversity. Appendix A, provides more detailed information about the organisms in the pocket field guide. Appendix B provides printable worksheets for the activities designed to get young people—
either individually or in groups—out on the land and actively investigating the natural world around them. 1 2 The Tundra Tundra is a mostly-­‐treeless landscape covered mainly by low, ground-­‐hugging plants. The word, tundra, comes from the Finnish word Tunturia, which means barren land. Generally, tundra occurs where a short growing season, low summer temperatures and long, cold winters make conditions difficult or impossible for trees to grow. Tundra is one of Earth’s major biomes. Biomes are large natural communities that are defined by the kind of vegetation that dominates them and adaptations that organisms (living things) make to live there. Other examples are forest, desert, grasslands, freshwater, and marine (the oceans). Where Do You Find It? In the Arctic, the largest expanse of tundra covers the area between the Arctic Ocean and the northern edge of the boreal forest, as well as most of the Arctic’s many islands. The main vegetation is low shrubs, grasses, sedges (grass-­‐like plants), forbs (low-­‐growing flowers and other leafy plants), lichens and mosses. Much of the Arctic tundra lies within 100 km of seasonally ice-­‐covered seas, where cold sea breezes keep temperatures during the growing season below what is needed for tree growth. Where you find tundra and the type of tundra depends very much on the climate. The map shows the Arctic tundra divided into bioclimate zones. Bioclimate zones have distinct climates that influence the types of plants that can grow in them. To a 2 large extent, as the map shows, these broad zones are determined by latitude—that is, how far north they lie. In southern regions of the Arctic, where boreal forest covers low-­‐lying areas, there is another kind of tundra: alpine tundra. It occurs at higher elevations, where the snow stays late and arrives early and where summer temperatures stay low enough to discourage trees. The vegetation is similar to Arctic tundra vegetation, and many of the same animals—or their close relatives—live there. Tundra Ecosystems An ecosystem is all the living things in an area and the ways they interact with each other and with the non-­‐living world around them. Within the very large area classified as a biome, there can be many different ecosystems. The ecosystem of a tundra pond, for example, is different from the ecosystem of a rocky Arctic plain, although they both fall within the tundra biome. Land-­‐based tundra ecosystems are shaped by low primary productivity. That means that the most basic organisms—the ones at the bottom of the food chain that all other organisms depend on—are scarce and tend to grow slowly. On the tundra, short, cool summers limit plant growth and slow the metabolic activity of other organisms, such as bacteria, fungi and invertebrates. As a result, there simply aren’t as many species of plants and small organisms as there are in a place with a longer growing season and a gentler climate. And there’s less for other organisms to eat. Tundra ecosystems might be simpler and less crowded with organisms than ecosystems in many other biomes, but they still perform important functions. Some, such as food production, are crucial for the livelihood of local people. Others are essential in the global climate system. Tundra-­‐based processes help control the exchange of heat and greenhouse gases in the Arctic and beyond—important factors in climate change. Because they are relatively simple and uncrowded, tundra ecosystems are also extremely vulnerable to change. If one species of insect disappears, there might be nothing to replace it—as a pollinator, as food for other species, as a predator keeping other populations in check, or as a processor of waste materials. If it is not replaced, then all the organisms linked with it could be affected. Effects of this sort—called cascading effects—can happen more quickly and cause more damage in the Arctic than in other regions. 3 Common tundra vegetation You can find more information about types of tundra at the website of The Circumpolar Arctic Vegetation Mapping Project, the source of the following images: www.geobotany.uaf.edu/cavm/download. Moist tundra with sedges, dwarf shrubs and mosses The photo on the left is from Russia, but typical of this type of tundra in many other places. Note that it naturally has barren spots, some formed by frost action. The photo on the right has many tussocks of cotton grass—common on eastern Russian, Alaskan and western Canadian moist tundra. Shrub tundra This is the most widespread tundra type and is increasing in some areas with warmer conditions, related to climate change. The photo on the left, from Canada, is dwarf shrub tundra: shrubs are generally less than 40 cm high. The photo on the right, from Alaska, is low shrub tundra: shrubs are generally over 40 cm high. Barren tundra types The photo on the left is mountain tundra. The variety and size of plants decrease higher on the mountain and farther north. The photo on the right is a herb barren: dry or wet landscapes with very sparse, low-­‐
growing cover of flowering plants, lichens, mosses and liverworts. Both photos are from Greenland. Changes and Threats Tundra is affected by climate change. The warmer summers and longer growing seasons mean that some types of tundra are increasing, and others are decreasing. 4 In particular, shrubs are getting bigger and covering more of the tundra, and other smaller vegetation types, including lichens, are becoming less common. Another change is that the amount of vegetation growth on tundra is increasing in some areas, filling in bare spots and getting denser and taller. In the summer, there is much less sea ice compared to 40 years ago, and it melts earlier in the year. This warms up coastal regions in particular. Snow also does not last as long on the ground in the spring, so the ground begins to warm up earlier and plants start to grow sooner. The dark earth and vegetation traps heat more than white snow does. When permanently frozen ground (permafrost) thaws, the tundra changes—sometimes turning into wetlands with completely different vegetation. Thawing of permafrost also releases carbon into the atmosphere, and that contributes to climate change. These are general trends and will not be noticeable each year or in all places—but studies at many locations in the Arctic, as well as studies based on taking a broad view of tundra from climate and satellite records, provide good evidence for these trends. Because greenhouse gases are still increasing in the atmosphere and the climate is continuing to warm, it is very likely that these trends will continue. Tundra can be damaged by activities that tear up the vegetation and often cause the permafrost to thaw where the damage has occurred. Sometimes this damage is part of building roads or doing seismic testing, but it can also occur from activities like driving ATVs on tundra. These are impacts that are not widespread, but they can last a long time, as the whole process of growth on tundra is slow. Tundra can also be damaged from pollution—for example, from oil barrels that are abandoned and then rust out and leak. 5 3 Equipment for Exploring the Tundra If you want to make the most of a field trip to the tundra, here’s a general list of useful equipment. Any special equipment needed for the activities in the next section of this manual is listed with the activity. Basic gear • Notebook and pen or pencil: Things to record on a field trip include: date, time of day, weather conditions, and location. The notebook can be used to record details of a specific project or activity, but it can also be used to make notes and sketches of things you observe. If you want to identify a plant or animal later, a few notes about its features and a quick sketch will make that a lot easier. • Measuring tape: Longer is better, and this should be at least 1 m long. It’s useful for measuring short distances or the size of larger objects (for example, the size of a crustose lichen). • Short ruler: To measure small things and show scale in photos. When photographing a small thing, such as a leaf or a caterpillar, place it beside a small ruler with clearly visible markings. That way you will know exactly how big it is. • Magnifying lens: Any kind of magnifying glass will make it easier to see the details of leaves, lichens, insects, or any of the other small things found on the tundra. • Camera: A cheap and simple camera or camera phone will work to record most of your discoveries or document a project. Taking an image of an interesting creature or plant means that you can leave it to live and grow in the tundra, and still have a ‘sample’ to study later. This is great for difficult to identify plants that you want to try and identify after. • Drinking Water: For thirsty explorers. Optional • Binoculars: Can be heavy and expensive, but they make it much easier to observe and identify birds and animals without disturbing them. On a field trip, several people can share one set of binoculars. • String and 4 tent pegs or short sticks: To mark out study plots It’s helpful to mark out a limited area to examine in detail, especially when exploring small tundra vegetation and looking for traces of tiny animals. String and a few pegs are all you really need. • Plastic bags: Sometimes it’s hard to identify plants and lichens in the field. Taking a few leaves or fragments of lichen as examples can help, and a couple of small plastic bags will protect them. While it is preferable to take pictures and leave sensitive tundra plants and slow-­‐growing lichens intact, sometimes it is easier to study a physical sample. If a student finds something they are really keen to take back and examine further, ensure that only small samples are taken and that multiple students don’t take samples from the same plant. • Compass: Direction is often important to where and how tundra vegetation grows, so it’s useful to be able to tell directions, even on an overcast day. It also helps you avoid getting lost! 6 •
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Field guide (a book or a person): A portable collection of expert information. Usually we think of a field guide as a book, but it could just as easily be a person who knows about the tundra (a scientist, an elder, someone who works on the land) and is willing to join the field trip. Snack: For hungry explorers. 7 4 Activities for Individuals and Small Groups 4.1 LISTEN LIKE AN OWL Goal: To deepen our understanding of owl ears. Location: Classroom or field Background information: Snowy owls have very sensitive hearing, and can pinpoint the location of prey animals under deep snow. Owls have no external ears. Instead they have ear openings at the sides of the head, behind the eyes. One ear opening is higher than the other. A ring of rigid feathers, the eye sockets and the beak form facial disks. These act as funnels, guiding light into the eyes and sound into the ear openings. This allows owls to see in near-­‐darkness and to catch prey animals without seeing them. Having the ear opening higher on one side than the other allows the owl to pinpoint the exact location of a prey item. Owls can triangulate where a sound is coming from by sensing tiny differences in the time the sound arrives at each ear opening. This allows the owl to pinpoint exactly how near or far, left or right, and up or down a sound is coming from. What to do: To demonstrate how the facial disks guide sound into the ear openings, have your students extend their own ears with their hands, by cupping the hands just behind the ears. Then ask them to hoot like owls. Now take away the hands and hoot again. Do they notice a difference in volume? The hoot will sound significantly louder with the hands placed around the ears. Having extra surface area around the ears allows more sound to be caught and funnelled into the ear canal. Questions to consider: • Why would the owl need this kind of hearing? • What other animals use this technique to improve hearing? • Why do you think those animals need super hearing? 8 4.2 GO SLUG HUNTING Goal: Discover if there are marsh slugs living in an area of tundra. Location: Field Background information: Marsh slugs are not common in the Arctic, and they are very hard to spot because they are so small. If you want to check for slugs in the tundra where you live, here’s the trick. Slugs like wet, dark places, so a sheet of wet cardboard dropped over tundra vegetation makes a perfect slug hideout. Equipment: • A few flat sheets of cardboard, maybe from old cardboard boxes • A magnifying glass What to do: Take a few sheets of cardboard (a few old, used cardboard boxes flattened out will work) and make sure they are damp. Place them over several patches of tundra vegetation, and leave the cardboard lying undisturbed on the tundra for 24 hours or so. Then lift the cardboard carefully and turn it over. If you’re lucky – and if there are slugs hiding in the local tundra – you should find that a few tiny slugs have crawled onto the bottom surface of the cardboard. The magnifying glass will help you see them more clearly. Record how many slugs you found and the kind of vegetation where you found them. Questions to consider: • What is the role of slugs in the ecosystem? • Why are they slimy? • What color is a slug’s blood? Why? 9 4.3: MAKE A TRADITIONAL STRING HARE Goal: Have fun with a traditional Inuit activity related to the hare. Location: Classroom or field Background information: String games and string figures are part of many traditions around the world, including the traditions of Arctic peoples. The string hare or rabbit (Ukaliq in Inuktitut) is a traditional Inuit string figure. It can even move! Equipment: • A piece of string or a shoelace 130 cm long • Access to the Internet or to an instructor What to do: Detailed instructions and an instructional video for making a traditional Inuit string hare are available at nature.ca/ukaliq/030act/021_str_e.cfm. Or, if you are lucky, there might be someone in your community—possibly a grandparent or an elder—
who knows how to make string figures and can teach the group. Learning to make a string hare provides an opportunity to talk informally with the children about the hare, its importance to other animals and people of the tundra, and about how people lived on the land in the past. Questions to consider: • What does a hare eat? What eats a hare? • How would hares be affected by temperatures? • What would happen to the hare if the Arctic warms up? 10 4.4 EXPLORE TRADITIONAL ECOLOGICAL KNOWLEDGE Goal: Learn about how people have been and are part of the local tundra ecosystem. Location: Classroom and in the community Background information: Not so long ago humans relied heavily on their local ecosystems to sustain them, providing them with most of their food, clothing and shelter. This has changed in much of the world, with food coming long distances to stock our supermarkets. Many of us are removed from our local food sources, relying on items from far away to sustain us. However, many Arctic communities still maintain a traditional lifestyle, living off of the tundra landscape around them. There is a wealth of knowledge held by the local peoples of these areas, but too often it is being lost. Whether you live in a community where these ways are still practiced or not, much of that knowledge remains. What to do: Have your students go out into the community and look for answers to some of the questions below. Suggest they ask grandparents or other family, community elders or teachers. Who else in the community might provide information? People who work on the land? People who study the tundra or who manage wildlife? Ask for suggestions. As a group, you might create a booklet, information sheet or a poster describing the traditional uses of tundra organisms and showing which ones were most important in your area. Questions to consider: • Traditionally, which plants were the most important food plants in your area? • What time of year were these plants harvested in? • How were they prepared? How were they stored? Were there plants used for fiber, or for dyes? • What animals were most often hunted for food? For hides? • How were they hunted? • How were they preserved? • Have there been changes in the tundra? • Are there differences in the species seen today on the tundra? 11 4.4.1 TRADITIONAL ECOLOGICAL KNOWLEDGE EXTENSION Goal: Explore local foods. Location: Classroom Background information: Traditional foods on the tundra were simple. Meat was the staple of the diet, from caribou, muskoxen, seals, whales, fish and even polar bear. Vegetables were mostly absent, with berries being one of the few plant foods. The most common tundra berries eaten are lingonberry (also known as cowberry or low-­‐bush cranberry), and cloudberry (also known as low-­‐bush salmon berry). Scurvy was not a problem as most meat was eaten raw. This preserved the natural vitamins, providing the people with all the nutrients they needed. As trade increased, flour was traded for fur, and fry-­‐breads and other new foods became a part of the diet. Over the past century, the traditional way of eating is being lost. Processed foods, high in saturated fats, sugars and chemicals are widely available. While some communities maintain a subsistence lifestyle, many peoples of the Arctic are now disconnected from the local foods that sustained them in the past. In recent years, there has been a growing movement to return to traditional foods. Evidence has shown that the western diet has resulted in an increase in health problems, such as diabetes and heart disease, across the Arctic. What to do: During the Explore Traditional Ecological Knowledge activity, students gathered information on traditional local foods. Some students may have grandparents or family with recipes and an in depth knowledge of local foods. Invite these elders to the class to share stories. Ask students to collect recipes, and bring a traditional dish. Share a meal of traditional foods, and discuss the following questions: •
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Do you know any traditional dishes from your area? Describe them. How was food traditionally hunted, gathered, prepared or preserved in your area? In what ways are traditional activities still practiced in your community? What traditional activities, foods or rituals have been lost to modern culture? Does it feel good to be eating foods from the local area? Would you prefer fast food? As you grow older will you try to maintain a connection to local, traditional food? Why, or why not? 12 5 Activities for Larger Groups and Classes 5.1 BUILDING TUNDRA FOOD WEBS Goal: To explore interactions among species and the impacts of change within a food web. Location: In the classroom or in the field Background information: This activity engages children in exploring the linkages among organisms, and between organisms and their environment. It also introduces concepts relating to biodiversity and ecosystem health. What is the difference between a food web and a food chain? A food web is made up of a whole bunch of food chains. Both of them show how energy moves and cycles through an ecosystem or across a landscape. A food chain is very simple, showing just one connection per organism. The reality is much more complex. On lower levels of a food web, organisms will have more connections. Small and large herbivorous mammals, insects, birds, snails and slugs might eat one plant. A large carnivore will have far fewer links in a food web, maybe just a handful of prey items and nothing preying on it. The more tundra organisms your students can think to put in their food web, the more complex and interesting it will get. The Energy Cycle What is the main source of energy for life on Earth? The sun. It is the beginning of the cycle, and it provides energy for vegetation (producers) to grow. The vegetation then feeds the herbivores (primary consumers). Meat-­‐eaters (secondary consumers) come in and feed on the herbivores. To close the loop, we have decomposers that break down all of the once-­‐living material of any of these organisms into nutrients that can be taken up by vegetation. It really is the circle of life. Producer: An organism that produces its own food, using energy from the sun. Plants, lichens and algae are producers. Lichens and Arctic willow are both primary producers. Consumer: An organism that cannot produce its own food and must eat other living things for energy. Consumers can be herbivores, carnivores or omnivores. Arctic woolly bear caterpillars, lemmings, hares, ptarmigan, caribou, snowy owls and wolves are all consumers. Herbivore: A consumer that eats only vegetation. Arctic woolly bear caterpillars, lemmings, hares, ptarmigan and caribou are all herbivores. Carnivore: A consumer that eats only meat. Snowy owls and wolves are both carnivores. Omnivore: A consumer that eats both meat and vegetation. Humans and bears are the main omnivores living on the tundra. 13 Primary An organism that eats only producers. A herbivore. This may consumer: includes insects, invertebrates, and small or large mammals that only eat vegetation. Secondary An organism that eats herbivores. This may be a carnivore or an consumer: omnivore. Decomposer: An organism that breaks down material that used to be alive. Fungi, bacteria and many insects are decomposers. Lichens can act as decomposers and producers. Why are the links important? These links between organisms are important for the organisms themselves, but also on a much bigger level. Changes in an ecosystem can have far-­‐reaching effects, because everything is interconnected. If you take away one organism, it can have an impact across the landscape. Even a small change in the population size or health of one organism in a food web can have big impacts on biodiversity in the area. Biodiversity is short for biological diversity. It describes the variety of life on Earth and the natural processes associated with it. As climate change alters ecosystems across the Arctic, maintaining biodiversity is an important conservation concern. Another important factor is pollutants moving through the food web. As toxic substances move up through the food web, they accumulate in higher and higher concentrations. Herbivores may eat polluted vegetation, and then those pollutants accumulate in their bodies. Carnivores, who have to eat large numbers of the herbivores to meet their energy needs, accumulate the pollutants from each prey animal. In this way, carnivores (and omnivores) can build up dangerous levels of toxins. This has happened in parts of the Arctic to caribou and marine mammals. Begin this activity in with small groups working together. Then bring the whole class together for the rest of the activity. Equipment: • Scissors • Tape • Pens or pencils • String • Life Linked to Tundra Field Guide • Student activity sheets (in Appendix B of this manual) PART 1. What to do in small groups: Have the students work in small groups, each with a set of blank species cards cut out. Ask them to draw and label as many local tundra producers, herbivores, carnivores, omnivores and decomposers as they can think of—one per card. Guide them in finding information on species living nearby if necessary. Each functional group must be represented in the cards in order to create a realistic web. Now students can practice making a food web, laying out the cards with producers near the bottom and carnivores at the top. Students can make connections by laying bits of string between the squares. 14 Questions to consider: • What is at the primary source of energy for all living things? • How does that energy travel between organisms? • Where does the food web end? • What role do decomposers play? PART 2. What to do as a class: Cut out the species cards provided in Appendix B and tape them to a board (this can be laid out on a table if a whiteboard or blackboard is unavailable), arranging producers at the bottom and primary then secondary consumers at the top. Using their Life Linked to Tundra booklets for reference, ask students what links exist between the species. Draw lines between the cards as they identify links. Ask students to name some of the species they chose for their own webs. As they name a species ask them to take turns coming up and adding it to the web, drawing in its food web links. Continue this until each different species has been put up. Discuss the food web and invite any comments on what links have been made. Depending on the age of your students you might want to stop here, or continue below to explore the food web further. Tell the students there has been an environmental disaster of some sort and a species has gone extinct. We’ll use the Arctic Hare as an example. Remove that species from the food web. Now remove any species that preyed upon the Arctic Hare. Explain to the students that if the hare is gone, then its main food source, the Arctic Willow, would grow rampant. It would compete with the lichen, shading it out and removing it from the web as well. Without the lichen the caribou/reindeer will be removed, and then anything that preys on them. Continue in this way until it seems reasonable to stop. Now have students evaluate what is left of the food web and discuss the following questions. Questions to consider: • Is the food web very complex? • Why might it be important to have so many links? • Would having a high level of biodiversity be beneficial to the food web? • How would removing one species affect the rest? • When you remove one species, how far-­‐reaching is the impact? • How might climate change affect the food web in your area? 5.2 FOOD WEB TAG Goal: Explore food web interactions and the energy cycle in a fun and energetic game. Location: Field 15 Background information: A food web is a set of connections through which the sun’s energy travels. Primary producers, like plants, store the sun’s energy. When these plants are eaten, the energy is passed into the consumers. When the consumers die, decomposers break down their bodies and use the stored energy for food. The minerals and nutrients broken down by the decomposers are then taken up from the soil by more plants – and the whole cycle starts again. The cycle is a never-­‐ending circle, and it is the basis for life in most of the world’s ecosystems. Equipment: • 2-­‐4 red Consumer armbands, bandanas or strips of cloth • 4-­‐6 green Decomposer armbands, bandanas or strips of cloth • Enough yellow Producer armbands, bandanas or strips of cloth for the remainder of the group • A timer or stopwatch Instructions: Review the definitions of Producer, Consumer and Decomposer. These are the three food web components being explored and acted out in this game. Consumers eat the Producers, and Decomposers bring back “dead”’ Producers by recycling nutrients. Define the play area boundaries, preferably somewhere flat with few obstacles. Assign the students roles. Select 2 to 4 students to be Consumers, giving them red armbands to wear. Select 4 to 6 students to be Decomposers, giving them green armbands to wear. The remaining students are the Producers, and receive yellow armbands to wear. Explain the following rules: Consumers like to eat plants, the Producers. When a Consumer tags a Producer they say “I EAT YOU!” Tagging is done gently: no biting, hitting, scratching or pulling! • When a Producer is tagged, they fall to the ground, dead. • Decomposers break down dead organic matter into nutrients that feed plants. Decomposers can bring a dead Producer back to life by tagging them and saying “I FEED YOU!” Now the Producer is alive and back in the game. Set the timer for 10 minutes. After this time, switch the roles around and play another round or two. •
Questions to Consider: • In what way is this tag game a cycle? How long could the game go on if we didn’t have a timer? Why? • What is getting passed around between the players? • What role do the Decomposers play in the cycle? What would happen if they were removed? • What is at the very beginning of this cycle, but not a part of the game? It is something very big, very far away, and without which this cycle would not exist. [Hint to leader: the sun.] 16 5.3 WHAT KIND OF TUNDRA IS NEAR YOU? Goal: Introduce participants to a local tundra ecosystem. Location: Field Background information: This activity is a field trip that introduces participants to the methodical monitoring methods used by scientists studying the tundra. It’s most suitable for organized groups of older children or school science classes. The activity is designed to structure the children’s exploration of the tundra, while still allowing them the freedom simply to look around and record what they see. Tundra vegetation studies are carried out through an international program: the International Tundra Experiment (ITEX). Some of the studies are based on observing and recording information in plots—just as you are doing in this field trip. Main questions addressed by studies based on vegetation plots are: •
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What are the current patterns and the trends in tundra vegetation types? What are the most important effects of climate change on tundra ecosystems? (Examples of these effects are changes in snow cover, water availability, soil temperature, nutrients and growing season length.) What are the risks for species or groups of plants and animals from changes that are likely to happen in the future from climate change? Other ITEX studies are based on experiments. For example, to see the effect on tundra of warmer spring and summer temperatures, scientists construct small open-­‐
topped chambers that act as greenhouses (see photo). They can then compare plots without greenhouses (called control plots) and plots with greenhouses. Other types of experiments involve removing snow earlier in the year from some plots, adding nutrients to some of the plots, or building a fence around some plots to keep plant-­‐
eaters out and look at the effect of grazing. 17 This photo shows a pair of ITEX plots on Ellesmere Island, Canada. Data from plots around the Arctic are combined and analysed. Some trends scientists have seen—
through comparing the plots with open-­‐top chambers to the control plots—include taller vegetation overall (greater canopy height) in the warmed plots, as well as more shrubs and sedges and grasses, and less lichen and moss cover. (Greg Henry) Types of tundra vegetation Rather than trying to identify all the species that you see on the field trip, focus on the types of vegetation and on identifying some common species of flowering plants and shrubs. •
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Lichens: See the pocket guide for information on lichens and identification of two common types. Mosses: Is one type of moss obviously dominant in your area? Mosses grow on shallow soils and in moist areas, since they are simple plants that do not have systems to transport water. Grasses and sedges: Sedges, which often have solid triangular stems, thrive in moist conditions. Grasses have nodes on their rounded or flattened stems and generally grow on drier, better drained terrain. Cottongrass, common in some areas, is a sedge. Small flowering plants: These are the most interesting to identify if you have a flower guide book. Even if it is not flower season, the leaves and forms of the plants are quite distinctive. Shrubs: See the description of Arctic willow in the pocket guide. Shrubs can be evergreen or deciduous (lose their leaves in the winter), and they can be upright or prostrate (growing flattened on the ground). See Section 2 of this manual for general information about types of tundra. See Appendix A for more detailed information about the organisms in the Life Linked to Tundra pocket guide and for links to further information. 18 Equipment: • Notebook, and pen or pencil • Measuring tape • Stakes, tent pegs or spikes, and flagging tape or string. • A ruler (one per pair of kids or small group). If the local tundra has good-­‐
sized shrubs, you might need meter sticks. • A camera • Life Linked to Tundra Field Guide • Activity sheets in Appendix B What to do: The data sheet gives the participants a task: to describe the tundra systematically. While doing this, they learn to distinguish different types of tundra vegetation, and they learn some of the conditions that shape tundra ecosystems. Follow-­‐up discussions could focus on classifying tundra, ecological relationships and impacts of climate change on tundra—and/or more on the actual plants and animal species that were observed. Before the trip • Assemble the equipment needed and print the two-­‐page data sheet for each pair (or small group) of children. • Select a site that will have adequate space and ease of access for setting up the plots. Take a look at the soil and vegetation and make sure that you have a marking technique that works. • Discuss the field trip with the children, establish working pairs or small groups, and plan out how the children will work together to accomplish the tasks. General site investigation This is where the leader can ask questions that get the children looking around them and sharing and recording what they observe. Throughout the field trip, have them keep a lookout for animals and for signs of animal presence. Plot study 1. Lay out plots. The standard is 1 x 1 m, but they can be bigger or smaller. For example, if the terrain has a lot of bare ground and is uneven, you might want to use bigger plots. Mark the corners (using tent pegs, stakes, spikes or flagging tape tied to twigs). It is a good idea to put string around the perimeter so that it is clear where the plot is—but you can also just use corner markers. 2. Point sampling within the plot. The points do not need to be marked. They can be selected randomly by tossing a marker into the plot and doing the measurements at the point where the marker lands. This marker could be a small toy, or a pen, or a glove, for example. A good number would be ten points within each plot, but this number could be halved for younger children. For each point, have the children work in pairs or small groups to: • Measure the canopy height. Using a ruler or meter stick, measure from the ground to the top point of vegetation at the 19 sampling point. Record this measurement in centimeters. Have the child holding the measuring stick keep it in place. • Identify and record what is at the top and at the bottom of the ruler or meter stick. This might be a type of plant (a shrub, flowering plant, lichen), or it might be bare ground, rock, or dead plant material. 3. Presence and absence of different plant types in the plots. After the point measurements have been made, have the children explore their plots and see, and record, what types of vegetation are present. You could also spend some time looking at the types of plants and identifying common ones. Questions to consider (in the field): • What kinds of information are scientists looking for when they do this? • Why would they want to know these things? • Why would they sample in this way? • What kinds of things can we learn about the larger environment by looking at this one small space closely? • What types of species are you seeing? • Why do you suppose they are growing here? • What might eat these plants? After the trip Discuss what you saw on the field trip. Some ideas: •
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Make a list of all the animals that were seen and all the types of animal signs (for example, tracks, feathers, bits of fur, droppings, pathways). Discuss the roles that these animals might play in tundra ecosystems. What do they eat? What eats them? Ask the children how they think the tundra might change with climate change. How might these changes affect the animals in your area? For example, climate change might lead to more shrub growth that might be good for moose. But less lichen growth could be bad for caribou or reindeer. Overall, how would you describe your tundra type? Have the children refer to their plot data for this—especially their observations on what types of plants were present. Is this typical of your region, or is it a lot different in other places nearby (places that are wetter, at different elevations or perhaps on different types of soils)? See Section 2 of this manual for examples of different tundra types commonly found in the Arctic. Ideas for doing more with the data that you have collected. •
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Calculate the average canopy height for each plot and for the site. There is a place to write this for each plot on the data sheet. Calculate the percent cover. You can do this for the measurements at the top of each point (canopy top) and the bottom of each point (ground cover). 20 Example: Canopy top Type of vegetation Number of times it occurs (or rock, soil or dead plants) in each plot Shrubs #1: 5 times; #2: 8 times; #3: 3 times; #4: 7 times; #5: 7 times. Small flowering plants #1: 5 times; #2: 3 times; #3: 3 times; #4: 1 time; #5: 3 times. Total for 5 plots 5 + 8 + 3 + 7 + 7 = 30 times 5 + 3 + 3 + 1 + 3 = 15 times You can estimate a percent cover from this. In our simple example, shrubs were recorded at 30 points of the 50 points measured (in the 5 plots), so you have 60% shrub cover at the top of the canopy (30 ÷ 50 x 100). Small flowering plants were recorded at 15 points, so you have 30% cover by small flowering plants. The remaining 10% might be a mix of bare ground, moss and grasses, which could be calculated for each type or just lumped together as other. Question to consider (in the classroom): •
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How could you get a better estimate? (Measure more points. Or measure more plots. The standard method measures 100 points in a 1 m2-­‐ plot.) How similar are the plots? If you ended up with plots that are very different, discuss the reasons, based as much as you can on the children’s recorded observations. For example, were some plots on more hilly ground, had less soil, in wetter conditions? 21 Appendix A: Species Information This section provides further information about the species featured in the Life Linked to Tundra field guide. The information is presented in the same order that it appears in the field guide. VEGETATION Lichens Lichens are a partnership of two organisms: a fungus and an organism capable of creating its own food—usually green algae or cyanobacterium (often called blue-­‐green algae). The fungus traps moisture and provides a protective structure, while the algae or cyanobacteria produce food for both partners. There are over 1,600 known species of lichens in the Arctic. In some areas, up to 50 species can be found in a 1 m2 plot. Of the known species, 133 are endemic, meaning they are not found outside the Arctic. The two lichens featured in Life Linked to Tundra are elegant sunburst lichen (Xanthoria elegans, a crustose lichen) and reindeer lichen (Cladonia rangiferina, a fruticose lichen), also called reindeer moss or caribou moss). Physical description: The body of the lichen, mostly composed of the fungus, is called the thallus. It can come in many different shapes, but it usually falls into one of the following categories: •
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Fruticose: Branching and shrubby lichens, growing upwards from the substrate. Reindeer lichen is an example of a fruticose lichen. Foliose: Low-­‐growing lichens with a leafy appearance. Clinging to substrate. Dog lichen and rock tripe are foliose lichens sometimes found in Arctic tundra. Crustose: Crust-­‐forming lichens that may grow on rock, bark or soil. A common type of lichen in the tundra, and often brightly coloured. Elegant sunburst lichen is an example of a crustose lichen. Habitat: Lichens grow in a huge variety of habitats and in a range of conditions, but their three basic requirements are a surface, time and clean air. That surface can be most anything—bark, wood, moss, rock, soil, glass, metal, plastic or cloth. Most lichen species use only one type of surface (or substrate). A species of lichen found growing on rock will likely always be found on rock, and a species growing on tree bark will most often be found on some type of wood. Range: Found on every continent, including Antarctica and in the Arctic. 22 Food: The lichen’s alga or cyanobacterium produces carbohydrates, which feed the fungus too. Reproduction: Lichens reproduce in several ways. Sometimes the fungal partner produces fruiting bodies or tiny, powdery spores. Sometimes bits of the lichen structure itself break off. Any of these forms can be carried to a new location by wind, water or animals, resulting in a new lichen. Life span: Large patches of crustose lichen have been estimated to be up to several thousand years old. However, it is difficult to determine how long lichens can live. They grow very slowly: crustose lichens might only grow between 0-­‐0.5 mm per year. Reindeer lichen grow faster, up to 6 mm a year. Lichen can survive long periods without water or light. They go dormant when they dry out and begin to grow again when there is more water and light. Some species can grow in -­‐20°C. Ecosystem functions: •
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Lichens are often the first lifeforms to be established on a bare rock or a barren site. As lichens grow, they trap dust, silt and water. When they die, they leave behind a layer of organic matter that can provide a substrate for seeds to germinate or mosses to establish themselves. Next herbivores can move in, followed by carnivores. Lichens are significant primary producers. Their biomass ranges from 2% in the low Arctic to 18% in high Arctic tundra and up to 65% in polar deserts. They form an important part of the diets of a number of Arctic animals. Lichens are an indicator of air quality. They absorb moisture and nutrients through their surface cells, which makes it easy for environmental pollutants and radiation to pass into the lichen, where they can be detected and measured. However, these toxins can also be absorbed by animals that eat the lichen, and then by the carnivores (including humans) that eat those animals. Reindeer lichen forms almost three-­‐quarters of the diet of some caribou and reindeer in winter. Human use: Lichens are eaten by many different cultures. In the past, Iceland moss (Cetraria islandica) was an important human food in northern Europe. It was cooked as a bread, porridge, pudding or soup, or eaten as a salad. Wila (Bryoria fremontii) was an important food in parts of North America. Rock tripe (Umbilicaria spp. and Lasalia spp.) has been used as a food source in North America when little else was available. Lichens have also been used as mild antibiotics in medicine and food preparation and fiber dyes, fuel, tinder, soap and in the perfume industry. Impacts of climate change: •
Impacts on lichens due to changes in Earth’s climate are expected to be gradual, but radical over time. Expansion of vascular plants and increased shrub cover in the Arctic will reduce lichen habitat and increase competition for space. Interesting facts: 23 •
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Caribou have special microorganisms in their stomachs, which let them digest lichen. The stomach contents of a freshly killed caribou are often eaten raw, as a delicacy. The partly digested reindeer lichen is said to taste like a fresh lettuce salad. However, people can’t digest untreated lichen in the way reindeer and caribou can. If the lichen isn’t boiled or soaked to make it digestible, it will give you a bad stomachache. Wolf lichen (Letharia vulpina) is poisonous to wolves. For hundreds of years, in both Europe and North America, it was used to control wolf populations. In Europe, powdered lichen was mixed with powdered glass and stuffed in reindeer carcasses. It was thought that the glass would cause internal lacerations that would increase the effects of the poison. Arctic Willow Scientific name: Salix arctica Arctic willow is related to the willow trees that grow below treeline. It is an important food source for many tundra animals. Physical description: •
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Small, ground-­‐hugging shrub that rarely grows taller than 15 cm Trunk and branches spread across the ground, forming a twisted mat Branches can put down new roots where they touch the soil Leaves are longer than they are wide; dull green on the upper surface, grayer and hairy on the lower surface, turning red in autumn Large, conspicuous catkins (reproductive bodies) grow upward from twigs Habitat: Arctic willow can grow in a wide variety of habitats, including Arctic and alpine tundra, mountainous regions, meadows, fens, bogs and around the edges of pools and snowfields. Range: It occurs throughout northern Canada, Alaska, Greenland, China, far eastern Russia, Iceland and as far south as the northern United States and northern Europe. Reproduction: There are male and female plants, and both produce catkins. The catkins contain nectar to attract insect pollinators. Male catkins also have brightly colored red or yellow pollen as an attractant. Life Span: Arctic willows usually live about 85 years, but a 236-­‐year-­‐old specimen was found in Greenland. Ecosystem functions: •
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Arctic willow is an important food source for most plant-­‐eaters on the tundra. Rock ptarmigan rely heavily on the frozen willow buds in winter. 24 •
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Arctic woolly bear caterpillars eat nothing but Arctic willow. They emerge from hibernation as soon as willow shoots start to appear on the tundra in June, and they feed all through June when the willow is at its nutritional peak. Arctic willow makes up to 95% of the diet of Arctic hares, year-­‐round. Impacts of Climate Change: •
Increased summer warmth and a longer growing season is already leading to taller and denser stands of Arctic shrubs, including Arctic willow. Interesting fact: •
Sometimes, on the branch of an Arctic willow, you can find a tiny growth shaped like a wooden flower. It’s called a willow rose, and it’s a gall—a deformation of plant tissue caused by an insect. The larva of a midge called Cecidomyia rosaria makes the willow rose. Through chemical secretions, the larva causes the leaves of the Arctic willow bud to grow in the shape of a tiny rose. Willow roses are easiest to spot in winter, when the willow’s leaves don’t hide them and before the adult midge emerges. HERBIVORES (PLANT-­‐EATERS) Marsh Slug Scientific name: Deroceras laeve This is one of a few species of slug that are adapted to life in the Arctic. Slugs are gastropods, closely related to snails, but they usually have no shell. Physical description: •
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Brown to dark brown, with faint dark spots arranged in groups Almost cylindrical shape, with widened posterior end Wrinkles on the skin, and thin colorless mucus The size of a pinhead as babies, and up to 1 cm long as adults Habitat: Places where the tundra is consistently damp. Range: Found worldwide, except for Antarctica, and as far north as Canada’s Arctic Archipelago. Food: Mainly vegetation, herbaceous plants. Reproduction: Reproduce year-­‐round, usually by self-­‐fertilization. Round-­‐to-­‐oval eggs are laid in clutches of up to 33 and hatch in 10-­‐15 days. The eggs are deposited in cracks and crevices in the soil or in leaf litter. The eggs can survive in water and sometimes travel downstream with moving water. The juveniles hatch underwater and climb to the surface. This is the only land gastropod that goes deliberately into water and can survive for days submerged. 25 Life span: Not more than one year; and as little as one month. Ecosystem functions: •
This species of slug is host to parasite larvae that can infect Arctic herbivores—particularly ungulates, hooved animals that chew cud. The larvae develop for part of their lifecycle within the slug (or snail) and then leave the slug to curl up on some vegetation. If an ungulate, such as a sheep, muskox, or caribou, eats that bit of vegetation, it also swallows the parasite, which continues the next stage of its lifecycle in the host mammal. Impacts of climate change: •
Warmer, wetter summers could mean favorable conditions for the slug, which in turn could increase occurrences of lungworm and related parasites. Interesting fact: •
Slugs have green blood. Instead of the iron compound we have in our blood, which helps turn it red, slugs and their relatives (snails, clams, oysters, and other molluscs) have a copper compound that makes their blood green. Arctic Woolly Bear Caterpillar Scientific name: Gynaephora groenlandica The Arctic woolly bear caterpillar is the juvenile form of medium-­‐sized grayish and rather hairy moth with very faint patterning on its wings. The moth lives for only a few hours or days. However, the caterpillar can live for many years. Physical description: •
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Newly hatched caterpillars are tiny and tend to stay out of sight Older caterpillars covered with long tufted hairs, ranging from black to yellow. Can grow up to 3-­‐4 cm long Habitat: Spends 95% of its life enclosed in a cocoon and hidden among rocks on the tundra, frozen solid. Caterpillar thaws and emerges in June; spends the month eating Arctic willow leaf buds and young catkins. During its active period, the caterpillar can often be found on rocks, basking in the sun in order to raise its temperature and speed up its metabolism. About the end of June, it retreats back among the rocks to spin a protective cocoon in preparation for winter. Range: Two mainly North American species, Gynaephora groenlandica and Gynaephora rossii range from Eastern Greenland to Siberia; one European species, Gynaephora selenitica, occurs across Europe, but less commonly in tundra locations. Food: The leaf-­‐buds and catkins of Arctic willow. 26 Reproduction: Caterpillars pass through several stages, called instars, before turning into moths. Because summer is cold and short in the Arctic, it can take several years for the Arctic woolly bear to develop from the first instar to adult moth. In most parts of the Arctic, the caterpillar probably develops for 7 years, but that development might be extended to 14 years or even 21 years in the far northerly locations. In its last summer, the caterpillar weaves a silk cocoon around itself and transforms into a moth. The moth does not feed and lives just long enough to lay eggs for the next generation of caterpillars. Life span: 7-­‐14 years, almost all as a caterpillar. There is some indication that a few live for 21 years. Ecosystem function: •
Food source for birds, including ptarmigan. Impacts of Climate Change: •
The caterpillar's development each year is limited by the short Arctic summer. If summers grow substantially longer, the Arctic woolly bear caterpillar might need a shorter time to turn into a moth. Interesting fact: •
The Arctic woolly bear caterpillar produces an antifreeze-­‐like substance that prevents ice crystals from forming in its cells during the long Arctic winter. Lemmings (Brown Lemming and Collared Lemming) Lemmings are small stout rodents in the mouse family. Among the most common are the brown lemming and the collared lemming. Brown lemmings include a couple of species: Lemmus trimucronatus and Lemmus sibiricus. The name, collared lemming covers several similar species belonging to the genus Dicrostonyx. They include the northern collared lemming, the Ungava collared lemming, Nelson's collared lemming, the Ogilvie Mountains collared lemming, Richardson's collared lemming, the Arctic lemming, the Unalaska collared lemming and the Wrangel lemming. Physical description: •
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Lemmings have short tails, stout bodies, small ears, small eyes and strong curved claws for digging. The average length for a female is 14.5 cm, and an average weight of 68 g. The average length for a male is 15 cm and average weight is 78 g. Collared lemmings have shorter tails than brown lemmings. 27 •
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Every part of the brown lemming’s body is covered with a long coat of fur, even the ears, tail and feet. It has a reddish-­‐brown back and rump with a gray head and shoulders. In the fall, brown lemmings acquire a longer, grayer coat. Collared lemmings change color with the seasons. In summer, a collared lemming has a black nose, grey cheeks, tawny ear spots, a chestnut collar, and a more or less prominent black dorsal stripe. In winter, it has a solid white coat. In winter, the collared lemming grows long paddle-­‐like claws on each forefoot. The claws allow the lemming to dig through hard, wind-­‐packed snow. Collared lemmings dig extensive networks of tunnels and nesting areas beneath the snowpack. They have even been reported burrowing through the wall of an igloo. The claws stop growing and are worn back down in the spring. Habitat: Both live in the treeless areas of the Arctic, but brown lemmings like flat, mossy meadows, while collared lemmings prefer rocky outcrops in the tundra. Range: Brown lemmings: primarily tundra regions of North America and Siberia. Collared lemmings: tundra zone of Alaska, Canada and northeastern Greenland; also on the Siberian tundra and on Novaya Zemlya and the New Siberian Islands in northern Asia. Food: Fresh grasses, sedges and mosses. In winter they eat frozen green plant material. Moss can make up nearly half their winter diet. They will also eat bark and twigs from Arctic willow and dwarf birch, berries, lichen and roots. They forage for 1-­‐2 hours at a time at 3-­‐hour intervals each day. Because their food is low in nutrients, they must eat a lot of it. Reproduction: •
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Brown lemmings: sexually mature at 5-­‐6 weeks; females can breed immediately after giving birth. After a three-­‐week gestation period, they give birth to 1-­‐13 young. Females can have one to three litters per year. Collared lemmings: breeding season runs from early March to early September, with a pause from mid-­‐May to mid-­‐June during spring break-­‐up. Females can have three to five litters in a year. During the mating season, females are aggressive and may bite or even kill smaller males. Gestation period is 19-­‐21 days. Litter size is 1-­‐7. When the female leaves her young, she covers them with nesting material. At 16 days, the young are weaned and venture above ground. Life span: 1-­‐2 years. Ecosystem functions: •
Significant food source for Arctic carnivores, especially ermines, Arctic foxes, wolves, wolverines, snowy owls, short-­‐eared owls, rough-­‐legged hawks, peregrine falcons, glaucous gulls, parasitic, pomerine and long-­‐tailed jaegers. 28 •
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The populations of collared lemmings fluctuate on an approximately 2-­‐
5 year cycle, thought to be controlled by weather and other factors. Lemming population cycles regulate the populations of several of their predators. Lemmings influence tundra vegetation, scattering willow seeds and fragmenting heaths during periods of excessive population. Lemmings are important scientifically as a keystone species. The health and abundance of lemming populations have a direct impact on the activities and reproductive success of many other animal species. At the same time they impact plant productivity and nutrient availability. Overall, this means that lemming cycles have big impacts on all levels of tundra ecosystems and can be an indicator of ecosystem health. Impacts of climate change: •
Brown lemmings are very inflexible in diet and habitat requirements. As a consequence, they will be quite vulnerable to changes to the tundra as climate change progresses. Interesting fact: •
The collared lemming is the only rodent that turns white in winter. Hares Scientific name: Lepus spp. The two species of hare that live on the Arctic tundra are the Arctic hare (Lepus arcticus), found in North America and Greenland, and the mountain hare (Lepus timidus), found in Europe. For an excellent online guide to the Arctic hare, along with educational materials, go to nature.ca/ukaliq/ Physical description: •
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Hares are larger than rabbits, with longer ears, bigger feet and long, strong hind legs. Hares living in Arctic regions typically have a white coat in winter, with black markings on the tips of the ears. This helps increase the temperature of ear tips. Both the Arctic hare and the mountain hare have brown summer coats, but the mountain hare keeps its white tail year-­‐round. Habitat: Arctic and alpine tundra and forested boreal habitats. They do not live communally like rabbits, although at times of high population, they sometimes form 29 small or large groups, generally outside of the breeding season. Hares live in above-­‐
ground nests, but often burrow in the snow in cold winter months. Range: Arctic hare are found above the treeline in tundra from the Northwest Territories of Canada east to Greenland, and north to Canada’s Arctic islands. Mountain hare are found in the tundra regions of eastern and northern Europe, Russia, Greenland and Iceland. Food: Green grasses, forbs, deciduous tree leaves in summer; shrubs, conifer needles, twigs, buds, bark in winter. Arctic willow makes up to 95% of the diet of Arctic hares, year-­‐round. Reproduction: Usually one, but sometimes two, litters per year. Litter size ranges from two to eight. Breeding season typically is from April to mid-­‐September, with an average gestation period of 50 days. The breeding pair remains together until the babies are born; then the male leaves within a few days to find another mate. Life span: 4-­‐5 years Ecosystem functions: •
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Hares are an important link in the food chain between plants and carnivorous animals. Some common predators in the Arctic are Arctic fox, red fox, gray wolf, lynx , ermine, snowy owl , rough-­‐legged hawk , and humans. Hares have fluctuating population cycles closely tied to their predator species and climate and habitat variables. The highest fluctuations in the cycles are in northwestern Canada. At the southern extent of their range, the when cycles are in a peak they can have twenty times the number of animals found in the population at the low point of the cycle.. At peak points in the cycles in northwestern Canada, there can be as much as 3,400 times more animals in the population than during the low points! Hares compete for food with other herbivores, such as caribou, reindeer and muskoxen. Impacts of Climate Change: •
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More freeze-­‐thaw cycles in winter can lock vegetation beneath ice, making it hard for hares and other plant-­‐eaters to feed. Climate-­‐driven changes in the mix of plants might force hares to find new ranges. Hares change their coats to brown in spring to blend in better with spring and summer vegetation. However, with spring coming earlier, some hares are still in their white winter coats when the snow disappears, making them easy prey for predators. Interesting facts: •
Normally hares do a four-­‐legged hop, each hop carrying them about 1.2 m. But the Arctic hare from northern Baffin Island in Canada and northward hops on its two hind feet when alarmed, like a kangaroo. 30 •
Hares have black eyelashes that act like sunglasses to protect their eyes from the glare of sun on snow. Rock ptarmigan Scientific name: Lagopus muta Ptarmigan are northern members of the grouse family. The rock ptarmigan species is actually a collection of about 30 subspecies found throughout the Arctic tundra, as well as in many temperate alpine regions. They are adapted for life in the north and do not migrate south in the winter. Physical description: •
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Chunky bodies about the size of a small chicken, with small wings and short legs and tail About 30-­‐40 cm in length Thickly feathered, including legs and feet Feathers on their feet allow them to walk on snow, and thick layers of feathers keep them warm Coloring changes through multiple seasonal molts to match the changing colors of the tundra: almost pure white in winter, brown in summer, and spotted brown, black, yellow and white in spring Males shed their winter plumage later than females Males have a red comb over their eyes Habitat: Elevated, rocky, sloped areas of tundra. Range: Circumpolar, north of Arctic Circle, including Russia, Scandinavia, Canada, Iceland, Greenland, and Alaska. Rock ptarmigan are the only land-­‐bird that reside year-­‐round on the Archipelago of Svalbard. Food: Adults feed primarily on leaves, flowers, berries, buds, twigs, and also eat mosses, insects and spiders. The young also feed on or are fed insects. Reproduction: In late spring, females lay up to 10 eggs in ground nests. The nests are lined with grasses, lichens, leaves and feathers. The eggs are spotted and blotchy, blending in with the surrounding vegetation. By autumn the young are nearly adult-­‐sized. Life span: 2-­‐4 years Ecosystem functions: •
Ptarmigan are food for a wide range of predators, from medium-­‐sized birds to the top predators in the Arctic, including humans. In North America, they are preyed upon by crows, ravens, magpies, red foxes, pine martens, mink, short-­‐tailed weasels, least weasels, gulls, northern harriers, golden eagles, 31 •
bald eagles, rough-­‐legged hawks, gyrfalcons, peregrine falcons, northern goshawks, snowy owls, wolverine, wolves, Arctic foxes, lynx, polar bears and humans. When the ptarmigan population changes, the populations of some predators also change. Nesting gyrfalcons on the Yukon North Slope in Arctic Canada show a pattern of population change that has been linked to cyclic changes in the population of ptarmigan, their primary prey. Impacts of climate change: •
Winter rain, followed by freezing, could have a devastating impact on ptarmigan in the tundra. This is because ptarmigan, along with caribou, are reliant on plants buried beneath the snow for winter foods. Heavier snowfalls caused by climate change would not necessarily impact ptarmigan, as they can find areas where snow has drifted and is shallow. Ice, however, effectively seals off the ground surface and would prevent the birds from accessing any food. Interesting facts: •
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In Iceland ptarmigan is served as part of a traditional Christmas dinner. It is usually served with potatoes, peas, beans, gravy and jam. Ptarmigan hunting season is one of the most anticipated events of the year for Icelandic hunters. In some Inuit cultures, there is a strict taboo against burning ptarmigan feathers. This tradition stems from a legend about two girls who associated with ptarmigans and later turned into thunder and lightning. There is a belief that burning ptarmigan feathers will bring on a heavy thunderstorm. Caribou and Reindeer Scientific name: Rangifer tarandus Caribou and reindeer are among the largest plant-­‐
eaters on the tundra. They both belong to the same species – Rangifer tarandus. Generally, caribou live in North America, while reindeer live in the Arctic regions of Europe and Asia. Caribou are wild animals, but many reindeer are domesticated. There are seven subspecies of Rangifer tarandus: reindeer (R. tarandus tarandus), wild forest reindeer (R. tarandus fennicus) and Svalbard reindeer (R. tarandus platyrhynchus) in Eurasia; and barren-­‐ground caribou (R. tarandus groenlandicus), Alaskan caribou (R. tarandus granti), Peary caribou (R. tarandus pearyi), and woodland caribou (R. tarandus caribou) in North America. Physical description: •
Ungulates, meaning they have cloven hooves and chew cud. Muskoxen are another Arctic ungulate species 32 •
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Only members of the deer family in which both the males and females have antlers; bull antlers can reach 1.2 m in width Short, stocky body that conserves heat, and long lean legs to help them move through deep snow Large, concave hooves adapted for travel through snow and for use as a scoop when looking for lichens under the snow Average male (across all subspecies) 167-­‐298 cm long, 87-­‐158 cm shoulder height, 66-­‐300 kg; average female (across all subspecies) 105.4-­‐234 cm long, 80-­‐139 cm shoulder height, 51-­‐156 kg Across all subspecies, male caribou larger than females by 10-­‐50% North American caribou larger than Eurasian reindeer Habitat: Most Arctic caribou and wild reindeer undertake long migrations each year, up to 5,000 km. Some, such as the Peary caribou on the islands of the Canadian Arctic Archipelago, do not migrate. Nor do the Svalbard reindeer, which live on Norway’s Svalbard Archipelago. Range: Rangifer tarandus are native to Arctic, subarctic, tundra, boreal and mountainous regions of northern Europe, Siberia and North America. Food: Caribou/reindeer diet changes with the seasons. In summer, they eat a variety of tundra plants, including willow and birch leaves, sedges and grasses. In winter, the diet consists primarily of lichen, especially reindeer lichens. Reproduction: Breeding season occurs in October. Caribou males will fight each other for the right to breed and will attempt to breed several females. Males breed with the females in best condition before breeding younger or older females. Females generally do not reach sexual maturity until they are 2.5 years old. Gestation is anywhere from 225 to 235 days, and calves are born in late May or early June. Life span: Average of 4.5 years Ecosystem functions: •
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Primary food source for wolves; important food source for some bears and smaller predators Major source of food and materials for many Arctic peoples Caribou droppings spread nutrients and seeds across the tundra, playing a significant role in the growth and diversity of tundra vegetation Impacts of climate change: •
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Climate change is causing an increase in freeze-­‐thaw events, which lead to layers of ice encasing the animals’ primary winter food, lichens. This leads to more energy expenditure to access winter foods and can reduce winter food availability. Encroachment of shrubs into tundra environments as climate warms creates competition for the vital lichen food source. Earlier spring break-­‐up affects some herds that migrate across rivers to reach their calving grounds. The result can be that calving occurs in less 33 desirable areas and the calves are forced to cross streams and rivers while still young and weak. Interesting facts: •
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Insects—mosquitoes, black flies, oestrid flies and nose bot flies— harass the herds, particularly in the post-­‐calving period and summer foraging season, forcing the caribou to travel long distances to escape the insects, a significant expenditure of energy during the key summer foraging season. The antlers of the Rangifer female are smaller than those of the male, but they are carried for a longer period of time. Caribou start growing their antlers each spring and are normally done the process by August. Male caribou shed their antlers in November or December, after mating, while females will often carry them until June, after they have given birth. Usually only the pregnant caribou keep the antlers that late. They allow the cows to defend their feed and displace large caribou from favored sites while nourishing their babies. Young caribou can outrun an Olympic sprinter when only a day old. Reindeer were domesticated in Eurasia 2000 years ago. The word caribou comes from the word xalibu or Qalipu of the Mi’kmaq language, from Eastern Canada. It means “the one who paws.” PREDATORS Snowy Owl Scientific name: Bubo scandiacus The snowy owl is one of the largest owls in the world. Unusually for owls, it is active during the day, rather than at night. Since snowy owls nest in the Arctic and spend their summers there, this pattern might be an adaptation to the almost-­‐
constant daylight of an Arctic summer. Physical description: •
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Yellow eyes, black beak, white feathers 52-­‐71 cm long; wingspan 125-­‐150 cm; weight 1.6-­‐3 kg Male almost pure white; female and juveniles have some dark scalloping; young heavily barred, with a lot of dark spotting Very thick plumage; thick layer of down; heavily feathered, taloned feet Black talons 25-­‐35 mm long Toe structure permits rotation of one of their toes to the back or front of the foot, allowing them to use a variety of perches and catch prey easily Ears located next to the eyes, with a circle of feathers (called a facial disk) around the eyes that directs sounds into the ears Silent flight feathers allow owls to creep up on prey 34 Habitat: Snowy landscape where they can disguise their white plumage. Rolling tundra preferred, with higher areas used as perching and nesting sites. Range: Found in Arctic regions of North America and Eurasia year-­‐round. They nest in northernmost reaches of Canada, Alaska and Eurasia; winter across Canada and northern Eurasia. Migratory patterns are irregular. Some years they migrate much farther south. They have been reported as far south as the American states of Texas, Georgia, the American Gulf states, southernmost Russia and northern China. Young males, the smallest sex and age class, migrate farthest south. Adult females, the largest sex and age class, remain farthest north year-­‐round. Food: In the breeding range, they eat lemmings and voles almost exclusively. In times of low prey density or during ptarmigan breeding season, the owls might switch to juvenile ptarmigan. Prey can vary significantly depending on what is available. They feed on a wide variety of small mammals, but will take advantage of larger prey, frequently following traplines to find food. Larger mammal prey includes hares, muskrats, marmots, squirrels, rabbits, raccoons, prairie dogs, rats, moles, smaller birds and furbearing animals caught in traps. Birds preyed upon include ptarmigan, ducks, geese, shorebirds, pheasants, grouse, coots, grebes, gulls, songbirds and even other raptors, including other owl species. Each bird needs roughly 7 to 12 mice a day, and one owl can eat more than 1,600 lemmings per year. Reproduction: Breeding occurs from February to March. The owls build their nests in the brush of high areas in the Arctic tundra. A male attracts a female by killing a prey animal (usually a lemming) and holding it in his mouth. Snowy owls commonly choose one breeding partner for life. Females lay 3-­‐11 eggs per clutch. Snowy owls are very protective of their eggs and nests, shrieking and diving at potential predators. Life span: Average 9.5 years Ecosystem functions: •
Because snowy owls prey predominantly on lemmings when available, the population cycles of lemmings and voles have a strong impact on snowy owl populations in the Arctic. In turn, owls may help regulate lemming numbers in some areas, playing a key role in the tundra food web. Impacts of climate change: •
Lemming cycles are becoming irregular in parts of the snowy owl range, including Fennoscandia and Greenland. The cause is thought to be related to climate-­‐change-­‐induced shifts in the quality and amount of snow. The lemming cycles directly affect the reproductive success of snowy owls, and snowy owls have declined or disappeared in these areas. Interesting fact: •
An adult snowy owl can eat 3 to 5 lemmings per day, or up to 1,600 per year. 35 Wolf Scientific name: Canis lupus spp. Wolves are among the top predators on the Arctic tundra. In a few locations, they share that position with bears, but the only other predator that can challenge them throughout most of the tundra is humans. All northern wolves belong to the species called gray wolf or Canis lupus, but there are different subspecies in different parts of the Arctic—tundra wolves in northern Eurasia, from Finland to easternmost Russia and Arctic wolves in northern Canada, Alaska and Greenland. Physical description: •
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Arctic wolves are often white in color, but can also range through red, gray or black. They are smaller than more southern gray wolves, and have smaller, more rounded ears and shorter muzzles. Tundra wolves’ coloration is typically a combination of grey, black, rust and silver gray, with long thick coats and dense underfur. They are larger than Arctic wolves and can measure over 2 m from nose to tail. Habitat: Wolf packs occupy a large home range (260-­‐675 km2 in summer). They can be found on the Arctic tundra, mountaintops and plains, as well as in coniferous and deciduous forests. Wolves shelter in dens during the winter and breeding season in a variety of locations. Bank burrows near water are common. Range: Wolves have been driven extinct in much of western Europe, Mexico and much of the United States. In the Arctic, wolves remain in Alaska, northern Canada, Siberia and Greenland. They have recently returned to Finland, Sweden and, to a limited extent, Norway. Food: They primarily hunt big game, including moose, caribou, mule deer, white-­‐
tailed deer, mountain sheep, bison and muskoxen. Small game, such as hares, lemmings, marmots, beaver, muskrat and mice, form a smaller proportion of their diet, while ground-­‐nesting birds, fish, berries, fruit and grass are an incidental part of the diet. Reproduction: Wolves mate for life. Mating season extends from late February to mid-­‐March. The gestation period is between 60 and 63 days. Pups are born in early May typically, but possibly later farther north. Average litter size is 7. Pups are weaned at 6-­‐8 weeks. Once they have been weaned, the pack adults disgorge meat from their kills, to feed them. Life span: 18 years in captivity. Ecosystem function: •
Wolves are the arch-­‐predator in much of their range, as the lion is in Africa. Grizzlies, cougars and polar bears will usually give way when faced with a pack of wolves. 36 Impacts of climate change: •
Wolves are able to switch between prey items easily, so a decline in a primary prey species population may not have a big impact on wolf populations. Because of this flexibility, Arctic wolves may be able to adapt to climate-­‐change-­‐induced shifts in the ecosystem better than many other predator species. Interesting facts: •
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Wolves in the Arctic travel much longer distances than wolves in the forest and sometimes go for days without eating. Arctic wolves are the only ones left worldwide that are not considered an endangered species. Further Information General Information The most comprehensive and up-­‐to-­‐date source of information about Arctic biodiversity, including the biodiversity of tundra, is the Arctic Biodiversity Assessment (ABA). The reports that make up the ABA, along with a variety of associated materials and information, are all available online at www.arcticbiodiversity.is/. The chapter on Terrestrial Ecosystems in the Arctic Biodiversity Assessment contains a wealth of information on currents status and patterns of change in biodiversity within Arctic Tundra Ecosystems. It can be found online at www.arcticbiodiversity.is/the-­‐report/chapters/terrestrial-­‐ecosystems. For even more information, go to the main website of the Arctic Council’s biodiversity working group, Conservation of Arctic Flora and Fauna (CAFF): www.caff.is/. For a broad overview of tundra ecosystems, see “Arctic tundra and polar desert ecosystems”, a section of the Arctic Climate Impact Assessment conducted by the International Arctic Science Committee, the Arctic Monitoring and Assessment Programme (AMAP), and CAFF: www.eoearth.org/view/article/150216/ For a quick illustrated guide to the tundra, go to Terrestrial Life in the Arctic: www.marinebio.net/marinescience/04benthon/arclife.htm EcoKids Teacher learning activities: https://ecokids.ca/teachers/about-­‐
environment/learning-­‐activities/ Hinterland Who’s Who: http://www.hww.ca/en/wild-­‐spaces/arctic-­‐tundra.html Species Information on the Internet (Listed alphabetically.) 37 Arctic willow Wildscreen Arkive. Arctic Willow: www.arkive.org/arctic-­‐willow/salix-­‐arctica/ Arctic woolly bear caterpillar Discovery Chanel, Frozen Planet. Caterpillar Survives Frozen Death: www.discovery.com/tv-­‐shows/frozen-­‐planet/videos/caterpillar-­‐survives-­‐
frozen-­‐death/ Discovery Chanel, Frozen Planet. Woolly Bear Caterpillars: www.discovery.com/tv-­‐shows/frozen-­‐planet/videos/woolly-­‐bear-­‐
caterpillars/ International Tundra Experiment (ITEX). Insect: Gynaephora groenlandica/G. Rossii: ibis.geog.ubc.ca/itex/PDFs/ITEXchapter9.pdf Caribou/Reindeer Smithsonian National Museum of Natural History, Arctic Studies Center. Caribou & Reindeer: http://www.mnh.si.edu/arctic/html/caribou_reindeer.html CARMA, the CircumArctic Rangifer Monitoring & Assessment Network: carma.caff.is/ Government of Yukon, Canada. Barren-­‐ground Caribou: www.env.gov.yk.ca/animals-­‐habitat/mammals/barrengroundcaribou.php Discovery Chanel, Frozen Planet. Celebration of the Reindeer: www.discovery.com/tv-­‐shows/frozen-­‐planet/videos/celebration-­‐of-­‐the-­‐
reindeer/ Hare Canadian Museum of Nature. Ukaliq, the Arctic Hare: nature.ca/ukaliq/ National Geographic. Arctic Hare fact sheet: animals.nationalgeographic.com/animals/mammals/arctic-­‐hare/ Wildscreen Arkive. Arctic Hare: www.arkive.org/arctic-­‐hare/lepus-­‐arcticus/ Wildscreen Arkive. Mountain Hare: www.arkive.org/mountain-­‐hare/lepus-­‐timidus/ Lemming Smithsonian National Museum of Natural History, Arctic Studies Center. Lemming: http://www.mnh.si.edu/arctic/html/lemming.html 38 University of Michigan, Museum of Zoology. Brown Lemming: animaldiversity.ummz.umich.edu/accounts/Lemmus_sibiricus/ Government of Nunavut, Canada. Brown Lemming: http://gov.nu.ca/environment/documents/brown-­‐lemming Lichen Lichens of North America: www.lichen.com/ The Microbial World: Lichens: archive.bio.ed.ac.uk/jdeacon/microbes/lichen.htm Wildscreen Arkive. Reindeer Lichen: www.arkive.org/reindeer-­‐lichen/cladonia-­‐mediterranea/ British lichens. What are lichens? www.britishlichens.co.uk/whatarelichens.html Marsh slug United States Department of Agriculture, University of Florida. Terrestrial Mollusc Tool. Deroceras leave: idtools.org/id/mollusc/factsheet.php?name=Deroceras laeve Rock ptarmigan The Cornell Lab of Ornithology, All About Birds. Rock Ptarmigan: www.allaboutbirds.org/guide/Rock_Ptarmigan/id The Cornell Lab of Ornithology, All About Birds. Willow Ptarmigan: www.allaboutbirds.org/guide/Willow_Ptarmigan The Cornell Lab of Ornithology, All About Birds. White-­‐tailed Ptarmigan: www.allaboutbirds.org/guide/White-­‐tailed_Ptarmigan Hinterland’s Who’s Who. Ptarmigan: www.hww.ca/en/wildlife/birds/ptarmigan.html Tundra Animals. Rock ptarmigan fact sheet: www.tundraanimals.net/tundraanimals/rockptarmigan.html Snowy Owl The Cornell Lab of Ornithology, All About Birds. Snowy Owl: http://www.allaboutbirds.org/guide/snowy_owl/id Canadian Museum of Nature, Natural History Notebooks. Snowy Owl: nature.ca/notebooks/english/snowyowl.htm National Geographic. Snowy Owl: animals.nationalgeographic.com/animals/birds/snowy-­‐owl/ Hinterland’s Who’s Who. Snowy Owl: http://www.hww.ca/en/wildlife/birds/snowy-­‐owl.html 39 Wolf Canadian Museum of Nature, Natural History Notebooks. Arctic Wolf: www.nature.ca/notebooks/english/arcwolf.htm International Wolf Center. Wolves of the World: www.wolf.org/wow/world/ Canada’s Polar Life. Grey Wolf: www.polarlife.ca/organisms/mammals/Terrestrial/wolf.htm Wildscreen Arkive. Grey Wolf: www.arkive.org/grey-­‐wolf/canis-­‐lupus/video-­‐ar17.html 40 Appendix B: Activity Sheets Building Tundra Food Webs worksheets The following four pages are designed for use with the large-­‐group activity “Building tundra food webs.” The activity is described in detail in Section 5 of this manual. The student worksheets are attached here, separately, for ease of printing. 41 Activity Sheet: Building Tundra Food Webs Food Chain Food Web What is the difference between a food web and a food chain? A food web is made up of a whole bunch of food chains. A food chain is very simple, with one connection per organism. A food web is complex. They both show how energy moves and cycles through an ecosystem as one organism consumes another. The arrows show the direction the energy flows.
The Energy Cycle What is the main source of energy for life on Earth? The sun. It is the beginning of the cycle, and provides energy for vegetation (producers) to grow. The vegetation then feeds the herbivores (primary consumers). Meat-­‐eaters (secondary consumers), come in and feed on the herbivores. To close the loop, we have decomposers that break down all of the once-­‐
living material of any of these organisms into nutrients that can be taken up by vegetation. It really is the ‘circle of life’. 42 Draw and label a tundra organism in each square use one space for the sun. 43 Arctic Willow
Lichen
Arctic Hare
Caribou / Reindeer
Rock Ptarmigan
Arctic Woolly Bear Caterpillar
Marsh Slug
Lemming
Snowy Owl
Wolf
The Sun
Humans
44 Put as many tundra species as you can think of into the following functional groups: Producer:
Primary Consumer:
Secondary Consumer:
Decomposer:
Why is it important?
These links between organisms are important for the organisms themselves, but also on a much bigger level. Changes in an ecosystem can have far reaching effects, because everything is interconnected. 45 What Kind of Tundra is Near You? worksheets The following four pages are designed for use with the large-­‐group field trip, “What kind of tundra is near you?” The activity is set out in detail in Section 5 of this manual. The student datasheets are attached here, separately, for ease of printing. 46 What kind of tundra is near you? Field trip to: Date: Name: This is a field trip to explore the tundra near your home. What kind of tundra do you have? Scientists lay out square plots on the tundra and use standard methods to record the plant life and conditions inside the plot. This includes not just the types of plants, but how tall they are, how dense they are, and what types are the most common. They might also record the temperature of the soil at the surface and a few centimetres below-­‐ground. Other important information is how much dead and rotting vegetation is in the plot, and if there are signs of plants being nibbled by animals. If these plots are marked so that the measurements can be repeated year after year, then scientists can look at how the vegetation is changing. You will use some of these techniques to explore the tundra near you. 47 1. General Observations Weather today Site description (Is it hilly? wet? dry? rocky? cold? altitude? coordinates?) Animals seen Signs of animals seen (tracks? droppings? signs of eating? broken branches?) Other observations 48 2. Plot data Plot number: Point Canopy height (cm) Plot dimensions: What is at the top? What is at the bottom? 1 2 3 4 5 6 7 8 9 10 49 Plants in the plot—what have you got? ! Lichen ! Moss ! Grasses and sedges ! Small flowering plants ! Shrubs Your plot data summary Average canopy height: Main type of vegetation at the top of the canopy: Main ground cover: 50