Invertebrate Identification

Shoreline identification and the release of live invertebrates is easily done by merely viewing illustrations.

Amphipods     Blackfly Larvae     Bristleworms     Caddisfly Larvae     Clams and Mussels     Cranefly Larvae     Damselfly Nymphs     Diving Beetles     Dragonfly Nymphs     Flatworms     Leeches     Mayfly Nymphs     Midge Larvae     Roundworms     Snails     Stonefly Nymphs     Water Boatman

Identifying invertebrates

Amphipod Crustacean Resemble small shrimp Swims on its' side Swims quickly before burrowing into clumps of vegetation Omnivores and scavengers on plant or animal material Requires well-oxygenated water Moderately tolerant of pollution May indicate fair water quality           Click here to read more detailed information.

Blackfly Larva Insect Complete metamorphosis Blackfly larvae resemble small grubs Head dark coloured Bottom-end swollen and fatter than the head-end Attach to the upper smooth surface of rocks using suckers on the bottom end Heavily populated rocks appear to have a stubble beard Larvae often attach to the bottom of a sorting tray Found in flowing water Omnivores Filtering collectors Pollution tolerant May or may not indicate poor water quality           Click here to read more detailed information.

Bristleworm Segmented worm Bristleworms esemble thin, reddish earthworms Bristles on each segment are not visible to the unaided eye Can tolerate low oxygen levels Pollution tolerant Large numbers may indicate poor water quality May indicate organic pollution           Click here to read more detailed information.

Caddisfly Larva Insect Complete metamorphosis Some larvae build tube-like cases to hide in Larvae resemble caterpillars with skinny legs Mostly herbivorous on algae and plants Some are predators that eat nymphs Some are collectors that build nests Larvae and adults are a favourite trout food Larvae are moderately tolerant of pollution and warm water Large numbers may indicate fair water quality           Click here to read more detailed information.

Clams and Mussels Mollusc Found in slow moving, warm rivers Clams are small, round and symmetrical Mussels are larger, oblong and lopsided Filter feeders on plankton and organic debris adrift in the current Can tolerate degraded or polluted environments Moderately pollution tolerant Large numbers may indicate fair water quality           Click here to read more detailed information.

Cranefly Larva Insect Complete metamorphosis Cranefly larvae resemble plump caterpillars with a knobby butt Larvae are found more often in the fall Herbivorous larvae shred leaf material (shredders) Adults do not feed Adults look like "giant mosquitoes" - what a scary thought, but they don't bite Moderately pollution tolerant Large numbers may indicate fair water quality           Click here to read more detailed information.

Damselfly Nymph Insect Incomplete metamorphosis Nymphs have three paddle-shaped tails Extendable lower lip is used to grab prey Predatory on mayfly nymphs and mosquito larvae, worms and anything else small enough to grab Moderately pollution tolerant Large numbers may indicate fair water quality           Click here to read more detailed information.

Diving Beetle Insect Complete metamorphosis Large diving beetles are fun to discover Breaths air from a "scuba tank" air bubble trapped under the wing covers Found in water both as adults and larvae Strong swimmers Carnivorous on larvae and small fish Adults are not useful as an indicator of water quality because they breathe from surface air bubbles           Click here to read more detailed information.

Dragonfly Nymph Insect Incomplete metamorphosis Nymphs are large, ferocious creatures Jet-powered butts squirt water for propulsion Lip is hinged and extendable to capture prey Nymphs express huge attitude with a large lower lip Predatory on larvae, nymphs, tadpoles and small fish Carnivorous - there's something scary about an insect that can eat a fish! Adults don't fold their wings; the wings lay flat and outspread Found in slow moving and still water Moderately pollution tolerant Large numbers may indicate fair water quality           Click here to read more detailed information.

Flatworm Small, pale blobs found in the vegetation or under rocks. Omnivorous on living or dead plants and animals. Old science textbooks are full of drawings that show flatworms growing two heads. What mad scientist would split those heads in half in the first place? Doesn't that hurt, or at least result in a "splitting" headache? Pollution tolerant Large numbers may indicate poor water quality           Click here to read more detailed information.

Leech Segmented worm Leeches are fun to watch swimming or inching along the glass of an aquarium. Parasitic on the blood of fish and birds. Pollution tolerant. Large numbers may indicate poor water quality.           Click here to read more detailed information.

Mayfly Nymph Insect Incomplete metamorphosis Three long tails Feathery gills are located along sides of the abdomen Diverse body types - flat, armoured, short or long and skinny and are adapted for different flow conditions Mainly herbivorous on algae and detritus. Nymphs require clean, oxygenated water. Pollution intolerant. Large numbers likely indicate good water quality and high oxygen levels.           Click here to read more detailed information.

Midge Larva Insect Complete metamorphosis Larvae occur in astronomical numbers and dominate many aquatic samples Some larvae have red blood Larvae resemble a short worm "C-shaped" and swim by flexing rapidly Appear to have no legs Omnivores feeding on small organisms, decaying matter and algae Pollution tolerant Large numbers may or may not indicate poor water quality and organic enrichment           Click here to read more detailed information.

Roundworm Roundworms are tiny worms that seem to thrash aimlessly in the water. Hair-like rather than round as their name suggests. Reproduce in astronomical numbers. Decomposers feeding on decaying plant material. Pollution tolerant. Large numbers may indicate poor water quality and water polluted with nutrients and organic material.           Click here to read more detailed information.

Snail Mollusc Herbivores that feed on algae scraped from stones and leaves Detritivores that feed on decaying matter Browse by means of a radula - a ribbon-like tongue embedded with thousands of "teeth" - scraped along rocks or leaves Lung-breathing snails have shells coiled like a tuba or spiral shells opening on the left side without a door. (Lung = Left) They obtain air from above the water's surface and therefore are not as sensitive to pollution and are not really good indicators of water quality Gill-breathing snails have spiral shells opening on the right side with a door (operculum). They rely on oxygen dissolved in the water and may be more susceptible to pollution Pollution tolerant Large numbers of lunged snails may indicate poor water quality and organic enrichment Large numbers of gilled snails may indicate good water quality           Click here to read more detailed information.

Stonefly Nymph Insect Incomplete metamorphosis Can be very large Great to find but kind of scary looking with armour and big legs Most are herbivores feeding on decomposing leaves coated in bacteria and fungus Two long tails and antennae They do push-ups to move water past the "arm-pit" gills Leave their dry, shed skins attached to dry rocks Found in deeper, faster water Very pollution intolerant Indicate good water quality with high oxygen levels           Click here to read more detailed information.

Water Boatman Insect Complete metamorphosis Are water boatman the cutest little bugs, or what? Can fly or swim Adults fly in search of deeper water for breeding and overwintering. Swarms of these swimming insects blacken shallow water in the North Saskatchewan River in Edmonton each fall. Omnivorous and feed on algae, detritus, micro-animals, small midge and mosquito larvae. Found in all types of water, moving or still. Boatman "scuba dive" with an air bubble trapped on their body. Not necessarily useful as indicators of water quality because the adults breathe surface air.           Click here to read more detailed information.