Life in a Pond, Study It

When is water not just water? When it comes from a pond! A jar full of pond water is a jar full of life. From bacteria too tiny to see, to fat tadpoles wiggling their way around their miniature world, pond water teems with plants, animals, and other living things. Young A variety of life Naturalists A pond is a very rich place—rich in nutrients that living things need to thrive. Water that runs into a pond when rain falls or when snow melts carries nitrogen, phosphorus, and other nutrients. Leaves and other plant parts that fall or wash in bring even more. You’re probably familiar with some of the things at home in a pond, such as ducks, turtles, frogs, and fish. But most pond residents are smaller—some so small you can see them only with a microscope. These critters are an important source of food for each other and for bigger living things around them. Life in aJar By MARY HOFF PHOTOGRAPH BY DEBORAH ROSE What are those little critters you scoop up from a pond? Five Pond If you’re lucky, your jar of pond water will contain members of all The Web Kingdoms five kingdoms of living things: • animals (such as insects of Life hen you scoop up a jar of and tadpoles) ike all living things, those in a Wpond water, you scoop up • plants (such as duckweed) Lpond can be put into categories living things too. Some might look according to how they get the • fungi (such as slime molds) GARY MESZAROS, DEMBINSKY PHOTO ASSOCIATES like see-through tubes. Some might (such as amoebas, energy to stay alive. have 10 legs. Some might look like • protists paramecia, microscopic algae) Producers combine water, tiny, darting dots. Some might • • monerans (bacteria). carbon dioxide, and energy from move by wiggling a whiplike tail. A the sun to make sugars to pond creature’s body parts, shape, Many of these creatures are too nourish themselves and, and behavior help it survive in its small to see, but all play an eventually, other living things. watery world. important part in the cycle of life Plants and some protists and of a pond. monerans are producers. • Primary consumers eat producers. When you eat a up some water with the bucket. A diving beetle grabs a meal. carrot, you are a primary Looking Scoop through the weeds so you consumer. can catch creatures that live there • Secondary consumers at Life too. Take your water to a well- take a closer look. Do you see eat primary consumers. When lighted place where you can little living things moving you eat a hamburger, you are a o get a look at life in a pond, study it. around? Use a turkey baster to secondary consumer. Tfind a grownup who can help Look in your bucket. Then transfer the ones you want to • Decomposers break you stay safe DEBORAH ROSE see, along with water, into a jar. down the remnants of other around Look through the sides of the jar living things into molecules, water. Then to see what you can see. Pour the which can then be used once put on old water into a thin layer in a white again by other life forms. shoes or plastic container or in a glass pie boots. Take pan on a piece of white paper. your grown- Look down at the living things up and a with a magnifying glass. bucket to the If you have a microscope, look edge of a at a drop under the microscope. Mary Hoff, Stillwater, is a free- lance science writer and the produc- pond. Scoop Draw a picture of what you see. tion coordinator for the Volunteer. July–August 2002 Damselfly Midge lar vae are long and skinny. Big Things nymphs are One kind, a bloodworm, is found skinnier than at the bottom of a id you catch some big things in dragonfly pond. It is red. your bucket? If you were fast D UNIVERSITY OF nymphs and have WISCONSIN EXTENSION and lucky, you might have tadpoles, Another kind, a frog eggs, snails, leeches, or even a three leafy gills glassworm or phantom midge baby fish! Here are some other on their rear larva, is see-through and has two things big enough to see without a end. They eat sets of two spots, one at the front magnifying glass: midge larvae and of its body and one at the back. water boatmen. Midge larvae eat copepods and Backswimmers are true bugs with GARY MESZAROS, DEMBINSKY PHOTO ASSOCIATES They are eaten daphnia. They are eaten by fish. big eyes and long legs that look like Duckweed is a plant with tiny, flat by fish. ANTHONY MERCIECA, DEMBINSKY PHOTO ASSOCIATES E.R. DEGGINGER, DEMBINSKY PHOTO ASSOCIATES oars. They live just below the water leaves that float and roots that Mosquito lar vae surface. They eat insects, snails, and hang down into the water. Duck- Fair y shrimp, or pond shrimp, eat detritus, bac- other small animals. Animals that eat weed captures energy from the sun have lots of legs and big eyes. They teria, and algae. backswimmers include fish, diving to grow. It is a valuable food for eat algae, detritus (bits of dead They make good beetles, and water scorpions. fish and ducks. things), and tiny animals. Fairy food for fish and shrimp can be hard to find in ducklings. Dragonfly and damselfly ponds with fish because fish nymphs are the young of flying gobble them up. Fairy shrimp eggs Diving beetle lar vae, known as insects with big wings. Dragonfly water tigers, hang from the nymphs are big and stubby. water surface and gobble up small creatures that swim by. GARY MESZAROS, DEMBINSKY PHOTO ASSOCIATES Adults eat tadpoles, fish, ANTHONY MERCIECA, DEMBINSKY PHOTO ASSOCIATES and insect can survive for 20 years after a larvae. When pond dries up. When water adult beetles returns, they hatch. dive, they carry GARY MESZAROS, DEMBINSKY PHOTO ASSOCIATES a bubble of air to breathe. Minnesota Conservation Volunteer July–August 2002 E.R. DEGGINGER, DEMBINSKY PHOTO ASSOCIATES Scuds are crustaceans—relatives W ater striders “skate” on top of Copepods are tiny of crabs and water. These insects eat mosquito Little crustaceans that eat shrimp. They bacteria, algae, and have 14 legs Things detritus. Some and eat copepods eat UNIVERSITY OF WISCONSIN EXTENSION hese creatures are tinier than detritus. Fish, mosquito larvae. ALEX RAKOSY, DEMBINSKY PHOTO ASSOCIATES frogs, and birds eat scuds. Tthe ones you met on the previ- They are important ous pages. If you can see them at food for fish. One kind of copepod is W ater boatmen all, they might look like specks in are the water. called a cyclops. Like the Greek true bugs that use mythological creature of the same their long legs like GARY MESZAROS, DEMBINSKY PHOTO ASSOCIATES name, the cyclops has one eye. oars to move through larvae and insects that get water. They eat algae trapped on the surface of the Daphnia belong to the group of and are eaten by water. Their long legs help spread crustaceans known as water fleas. water scorpions, out their weight so they can walk Each daphnia has an eye, a pointy dragonfly nymphs, on water instead of sinking. head, and two antennae that help it GARY MESZAROS, DEMBINSKYand PHOTO fish. ASSOCIATES move about in jerky strides. Its 10 Whirligig beetles zip around in legs push detritus, algae, and tiny W ater sca venger beetles, like circles on the water. Their eyes animals toward its mouth. Daphnia diving beetles, carry air when can see above and below water are good food for small fish. they dive. Water scavenger E.R. DEGGINGER, DEMBINSKY PHOTO ASSOCIATES beetle larvae have huge jaws Amoebas are protists, one-celled and eat other animals. organisms. They live at the bottom of a pond. The name amoeba comes from the Greek word amoibe, which means “change.” This blobby creature can readily change shape. It GARY MESZAROS, DEMBINSKY PHOTO ASSOCIATES eats by stretching its body around at the same time, as they search its food—bacteria, algae, and other for other insects to eat. tiny creatures. E.R. DEGGINGER, DEMBINSKY PHOTO ASSOCIATES E.R. DEGGINGER, DEMBINSKY PHOTO ASSOCIATES Minnesota Conservation Volunteer July–August 2002 One-celled diatoms are brownish Microscopic and shaped like tiny covered boxes. Their shells contain silica, a hard Things mineral. Most diatoms f you use a microscope, you might photosynthesize. That makes them Ibe able to find some pond things that are too small to see otherwise. ALEX RAKOSY, DEMBINSKY PHOTO ASSOCIATES Paramecia are oval-shaped protists Bacteria are extremely tiny covered with hairs, called cilia, that creatures. Many decompose dead propel them through water. Cilia also plants, animals, and other living E.R. DEGGINGER, DEMBINSKY PHOTO ASSOCIATES help the paramecium push food things, releasing nutrients that can ALEX RAKOSY, DEMBINSKY PHOTO ASSOCIATES an important source of energy for the toward its mouthlike indentation. then be used again by other life When you see a desmid, you might pond ecosystem. Many paramecia form partnerships forms. Bacteria are food for mussels, think you’re seeing double. It has with algae, which capture energy daphnia, and other small creatures. A two parts that are mirror images of Dinoflagellates are named after from the sun to help them stay alive. single drop of pond water can hold each other. Desmids come in different their long tails, called flagella. When millions of bacteria. shapes. Sometimes they live in they wiggle their flagella they move W ater mites look like swimming colonies. through the orange or red dots.

Load more