COLUMN-ROW-DIAGONAL-INTERPRETATIONS The following are plausable linkages among the members of each column, row and diagonal. Students may come up with different, yet acceptable, relationships. Column "C": Loons will feed on frogs, smaller perch and walleye and pond snails. Walleye will also eat frogs and tadpoles. The connections of the top four members to fungi are less direct. The fungi assist in decomposition, "recycling" nutrients back into the water for use by plants. Some of these plants, in turn, are grazed by snails. Others float around in great numbers, making the water cloudy or shady, and thus more tolerable for the light-sensitive walleye. Some form the base of a food web that eventually includes frogs, walleyes and loons. Column "OM": Detritus forms the food for both crayfish and mosquito larvae, which in turn are eaten by otters and yellow perch, respectively. Otters will also eat yellow perch. All of the animals eventually die and / or are eaten, and parts will add to the detritus in the lake. Column "MU": Bacteria, as decomposers, help to recycle nutrients back into cattails and pond weed. Cattails will break the wind and reduce wave action, making more of the lake accessible to water striders, which may then fall victim to small pike lurking in the pond weed. Column "NI": Emerald shiners, which school in shallow and open water and suckers are likely prey for osprey hovering above. Shiners, in turn will feed on shrimp. White suckers will search along the bottom for bristleworms. The worm assists in decomposition, breaking down detritus and contributing nutrients that may be used by plankton that is eaten by the shrimp. Column "TY": The sun provides energy that is trapped and transformed by the phytoplankton, which are in turn eaten by the zooplankton and clams. Bladderworts also use the sun's energy, but also trap zooplanktons in their bladders, absorbing nutrients as the tiny animals decompose. Row "B": The sun provides energy for the growth of cattails, which in turn may attract and shelter the food of the other three row members. Loons, otters and osprey all compete for similar types of food. Otters may also take young loons or loon eggs. Row "I": Mosquito larvae and water striders may be eaten by either frogs or emerald shiners and emerald shiners may eat frog eggs and tadpoles. Large frogs may eat small emerald shiners as well. Young emerald shiners eat phytoplankton but it is not eaten directly by any of the others although phytoplankton may form the food of small animals that are eaten. Row "N": Zooplankton may be directly consumed by the young of all three fishes in this row, and by the shrimp as well. Slightly larger fishes will eat shrimp, and both walleye, yellow perch and pike will eat smaller representatives of the other. Walleye and yellow perch of the same size may also compete for available food. Row "G": Pond weed and bladderwort can provide some shelter and protection for snails, crayfish, and young white suckers. They also give off oxygen that can be used by all three animals, which contribute carbon dioxide back to the plants. White suckers will feed on snails. Row "O": Both fungi and bacteria have a hand in creating, and further decomposing, the organic materials that hold both bristleworms and clams and provide food to worms. Diagonal "C-B/TY-O": Who eats whom dominates this diagonal. Loons may eat mosquito larvae, young pike, white suckers and clams. Northern pike will eat white suckers and mosquito larvae and young loons. White suckers will eat small clams and pike eggs. Diagonal "C-O/TY-B": Fungi help break down woody and other vegetation into smaller particles of detritus that are made even finer through the feeding action of crayfish. The crayfish in turn are eaten by northern pike, which also eat minnows. The sun provided the energy to grow the vegetation in the first place, and keeps the lake at a temperature where the other members may function. Definitions: Biotic: of or pertaining to life and living organisms Habitat: the local environment in which a plant or animal lives; includes the food, water, space and shelter necessary for survival. * Modified from Fish Ways Aquatic Resource Education Program, Ontario Ministry of Natural Resources