3Aquatic Macro Invertebrates Aquatic = water Macro = visible with your eyes
4Aquatic Macro Invertebrates Aquatic = water Macro = visible with your eyes Invertebrate = animal without a spine like a mayfly
5On the Big River Journey Boat, you’ll see. . . Aquatic Macro Invertebrates!
6Aquatic invertebrates These are tiny organisms, such as insects, that live in lakes, ponds, and rivers. We hardly noticed them, but they serve an important role. They feed on algae and other plants and are the base of the aquatic food chain daphnia (water flea) amphipod
7What’s an aquatic food web or food chain? It’s the story of what eats what. It includes everything that lives in or near the water:Big things: people, turtles, raccoons, fox, eagles, ducks, birds, big fish, little fish, seaweed,frogs, clams and mussels.Little things: macro invertebrates,insect eggs, snails, algae, aquatic worms, tadpoles, phytoplankton (tiny aquatic plants), zooplankton (tiny aquatic animals).
10Did you know?Many aquatic invertebrates, like this damselfly, spend their nymph stage in water. A nymph is the stage of development between egg and adult.When the nymph development is complete, the mature nymph climbs from the water and flies off to begin its adult stage. It then breeds and returns to the water to lay eggs. The cycle begins again.Damselfly nymph adult
12Mayflies may spend two years as nymphs living in water before developing into adults and flying in the air. After hatching as adults, they live from a few hours to three weeks. As adults, they do not eat--they have no mouth parts! The job of adult mayflies is to mate during their short life. Females return to the water to lay their eggs mayfly nymph
13A Mayfly hatch on Lake Superior Mayflies are highly sensitive and can only live in clean water
14The MosquitoMosquitos undergo four stages of development over a day period.They begin life as an egg laid on the surface of ponds and quiet waters.In the larval stage (left), they hang and breathe from the water surface, and feed on algae and microscopic animals.In the pupa stage, they also hang from the water surface and may swim about.When they emerge as adults, they rest on the water surface to dry their wings then fly off to mate and return to the water to lay their eggs. If the female has had a blood meal, more eggs will develop. Yes, only female mosquitos bite.
15Giant Water Bug Giant Water Bugs can grow to 3” They use their forelegs to grasp and hold a tadpoles or other insects as they thrust in their sucking mouthparts.They live in lakes and ponds.
16Macro Invertebrates can tell us if the water is clean or dirty. Some can survive in both clean and polluted water--leeches snails
17Macro Invertebrates can tell us if the water is clean or dirty. Some can survive in Dragonflies: the nymph stagemedium clean water (left) lives in the water 3-4 years before emerging as a flying adult dragonfly (right)!
18Macro Invertebrates can tell us if the water is clean or dirty. Some can survive ONLY in clean water--mayflies caddisflies
19Macro Invertebrates can tell us if the water is clean or dirty. Every species of animal has a range of physical and chemical conditions in which it can survive.Some invertebrates are sensitive and will not survive in polluted waters, others will tolerate a little to a lot of pollution.In the cleanest ponds, lakes, and rivers, you’ll find the greatest diversity of aquatic invertebrates.In polluted waters, only a few species can survive.
20Kinds of Ponds--Clean! + Natural shoreline with a variety of plants + no man-made structures+ room for lots of wildlife
21Kinds of Ponds--Medium Clean + Natural shoreline+ grasses at shoreRain runs off from parking lots (cars leak oil and this washes into the water)Urban area with limited wildlife habitat
22Kinds of Ponds--Polluted - No plants next to shoreline- chemical pollution+ Some trees might attract wildlife(Arizona)
23Collecting Specimens Take the “D” Net and a bucket to the pond -->drag the net through the weeds along the shore in the shallow water-->Examine net for invertebrates, hand pick out inverts and place into bucket. . .Repeat--Stop and listen to the sounds of nature
24Aquatic Invertebrates in the Winter In the winter, invertebrates are inactive.They’ve adapted to survive over-wintering, freezing and then thawing.Insect eggs wait in the mud for the water to warm in the spring.Algae still grows and fish swim about.
26Photo credits:• Photos from Wikimedia Commons, a copyright free internet photo source or other sites as noted• BRJ photos and others by Kate Hintz, Science Museum of MN• Photos from vernalpool.org, used by permission• Lyndon Torstenson, NPS