2 What is a stream? A lotic habitat (flowing waters) A transporter of inorganic and organic materialA habitat for many species of fish, insects, birds, mammals, plants, and microrganismsstream is used to describe flowing waters (or lotic habitats). This includes rivers, creeks, branches and runs. When streams are impounded in a lake or reservoir (lentic habitats), the biological, chemical and physical characteristics of the stream often change significantly. Here we will only discuss lotic (flowing water) habitats (although habitats in large pools may have lentic properties).Streams remove inorganic and organic materials from the landscape by water transport. This process contributes to the shape and dimensions of the stream itself. The geologic history and characteristics underneath the watershed also strongly affect the morphology of the stream.
3 What is a Benthic Macroinvertebrate? Why use them?Easy to collect and identifySome are indicator speciesSome are sedentary and have long life cycles, so can act as continuous monitors of water qualityMacros are aquatic insects, mollusks and crustaceansMacros live in various stream habitats and derive their oxygen from the waterAnimals retained by a net with a mesh size greater than 1/5 of a mm
4 Macroinvertebrates are affected by: - Resource availability- Pollution inputs (organic and inorganic)- Available habitat- Velocity and volume of water (flow)Why are theyimportant?- They are the link in the aquatic food chainThey eat algae, leaves,and other small macroinvertebrates, which are then eaten by larger animals like fish, who are eaten by birds, racoons, snakes, and people
5 Why Monitor Aquatic Systems? Provides education about streams near usAssess the health of streams and our waterwaysBuild local awareness about water qualityDocuments the quality of streams overtimeDetect a pollution problemDetermine places in need of restorationMay influence decision-making of local, state, and federal governmentsThe monitoring of streams and rivers yields an understanding of processes and patterns in the watersheds where people live, play and work.
6 What Is Point Source Pollution? Industrial DischargeSewage treatment plantExposed leaking sewer pipeRegulated by EPD through a permitting processPollutant source more easily identified (point to source)
7 What is Non-point Source Pollution? Erosion SedimentFertilizers, pesticidesAnimal wastesRunoff from roads and parking lotsIllicit Spills and illegal dumpingLeaking septic systemsThe #1 cause of water quality problems in North CarolinaNo easily identifiable source and everyone contributes
8 Biological Communities Definition- a group of plants, animals, bacteria, and fungi living in a particular areaWhy is it important? It reflects the overall ecological integrity of a system because the organisms integrate the chemical and physical aspects of the environmentCommunities vary with microhabitat
9 What is Biomonitoring?Biological Monitoring Definition- The use of organisms and their biological responses to evaluate changes in the environmentWhy important? Reveals the effects of differentpollutants or other changes in environmental changes.The presence of macroinvertebrates indicate both thethe quality of water and habitatThis data is often collected and used toassess the human impacts on a system
10 Kicknet Sampling Face it upstream Place rocks on net Make sure there is a bow on the netKick for one minuteEnsure that water does not flow over the top of the net or escape around the sidesTogether bring sides together slowly and bring net out of H20 in a forward sweeping motionKick net is facing upstream to the right. Note the bow in the net: this is important for creating a depositional area where insects can be accumulated. Weighting the net with rocks ensures that the net remains on the bottom of the stream. Washing large rocks by hand will greatly enhance capture success and is an important part of the procedure. When removing the kicknet from the water, ensure that no water washes over the top of the net. Bring the sides together and slowly bring the net out of the water in a forward sweeping motion. Sorting out the macroinvertebrates from the kicknet should take two people 20 minutes (see the next section). Organisms should be roughly sorted into general taxonomic groups (mayflies, stoneflies, etc) and placed into partitioned containers (e.g., ice trays) for further identification.
12 Picking a site Suitable Riffles Small Safe to wade in Will not wash water over top of kick netNot suitable riffleThis is perhaps as small a stream as you might wish to sample for monitoring reasons (sample nothing smaller), but this stream is more than six feet wide and is actually a fourth order streamPic 2- The riffle in the foreground of this picture is too large to safely or effectively wade for sampling. The section upstream of the white water (near the black pack) is more appropriate for sampling.
13 Leafpack Sampling Place pan underneath leaves Scrape material into pan *+Leafpack accumulated behind a small log. Note the various stages of decomposition of leaves (some are green, some brown and partially decomposed). To collect this leafpack, a volunteer would carefully place a pan underneath the leaves and then gently scrape the material into the pan.Place pan underneath leavesScrape material into panSort and identify the macroinvertebrates
14 Pollution-sensitive Macroinvertebrates CaddisfliesHellegramitesMayflyStonefliesPlanarianGilled snailRiffle beetle adultWater pennyA healthy stream will have various pollution sensitive macroinvertebrates present
15 Stonefly Nymph Measure 8-15mm in length (not including tails) 2 tails 2 sets of wing padsBranched gills between legs on underside of bodyYellow to brown in color; often patterned yellow andbrown when matureSuperficially similar to certain flattened mayfly nymphs, however stonefly nymphs always have two tails, prominent antennae, and two claws at the end of each leg.Stoneflies are not tolerant to low levels of dissolved oxygen and therefore prefer cold, swift-moving streams. The streamlined, flattened bodies of stonefly nymphs enable them to move about the rocky streambed in rapid currents
16 Mayfly Mature larvae measure to 3/4 inch in length (excluding tails) Two rows of long hairs present on inside of front legs2 or 3 tailsSlender antennaeThe conspicuous hairs growing on the inner front legs are used for filtering food particles from the water.Brush-legged mayflies may be minnow like with a vertically oriented head and three tails (as pictured) or may be more flattened with a horizontally oriented head and two tails.
17 Antennae reduced and inconspicuous CaddisfliesUp to one inch in lengthBuild distinctive cases made of sticks, rocks, sand, plant material and/or other debrisThree pairs of legsAntennae reduced and inconspicuous
18 Hellegramites Measure 3/4 - 4 inches in length. Body is elongate and somewhat flattened.Large pinching jaws.Lateral appendages along the length of the abdomen.Cotton-like gill tufts on underside of abdomen.Abdomen terminates in two small prolegs, each bearing two claws.Short inconspicuous antennae.Feed on other aquatic insects.Hellgrammites are usually found on the underside of large rocks in cool, slow-moving streams.Handle hellgrammites carefully, larger individuals may deliver a painful pinch!
19 Water Penny Measures 1/4 inch in length Flat disk-like body Head and legs concealed from above6 legs and branched gills on undersidePrefers cold running waterWater pennies prefer cold, fast-moving streams. Their smooth, flattened bodies enable them to resist the pull of the current. Water pennies are usually found on smooth rocks where they graze on attached algae
20 Riffle Beetle Adults Riffle beetles measure approximately 1/16 to 1/4 inch in lengthBody small, usually ovalLegs are longAntennae are usually slenderRiffle beetles walk slowly underwater,they do not swim on the surface
21 Gilled Snail Shell usually opens on right Shell opening covered by a thin plate (operculum)
23 Dragonfly Larva Measure between 0.5-2.0 inches in length Large eyes Two pairs of wing padsLarge round or oval abdomenAbdomen terminates in three small pointed structuresCan be readily distinguished from other species by the presence of a large jaw which is modified for grasping and covers the underside of the headPrefer cool still water, often found among vegetation and leaf packs or burrowed in sediment
24 Damselfly Nymph Measure 1/2 to 1 inch in length Large eyes 3 broad flattened gills at end of abdomenAbdomen usually much more narrow and slender than that of dragonfliesUnderside of head covered by a large jaw which is modified for grasping
25 Cranefly Larva Measure 1/3-2 inches in length Plump caterpillar-like segmented bodyHead is usually retracted into the bodyMilky green to brown colorFour finger-like lobes at back end of body
26 Sowbug Measure 5-20 mm in length. Clear whitish to pink in color. Dorsoventrally flattened (side to side).Seven pairs of legs, the first two are modified for grasping.Found in shallow freshwater on rocks or detritus.
27 Scud Measure 5-20 mm in length. Clear whitish to pink in color. Laterally flattened (top to bottom).Seven pairs of legs, the first two are modified for grasping.Found in shallow freshwater springs, streams, lakes and ponds.Most species feed on detritus.Scuds are an important food source for many fishes.
28 Crayfish Measure up to 6 inches in length Have 5 pairs of walking legs, thefirst pair with large pinchersResembles a small lobster Crayfish are usually active only at night. During the day they hide in burrows or under rocks.Crayfish are omnivorous, eating both plants and animals.
29 Pollution-tolerant macroinvertebrates Aquatic wormBlack FlyLeechLunged snailMidge FlySome macroinvertebrates can survive or even thrive in polluted water. An unhealthy stream may only have a few types of non-sensitive macroinvertebrates present
30 Midge fly Measure up to 1/2 inch in length Body small, cylindrical, and slightly curvedOccasionally deep red in color, otherwise variously coloredTwo small prolegs just posterior to headFrequently found in bottom sediments of lakes, streams, and ponds where they feed on deposited organic material
31 Black fly Measure to 1/2 inch in length Body cylindrical and widest posteriorlyAbdomen terminates in an attachment discHead usually possesses fan-like appendagesBlackfly larvae prefer cold running water and are usually found attached by the end of their abdomens to rocks, woody debris, or vegetation in the currents of rivers and streams.
32 Leech Measure 1.0 mm to 5.0 cm in length. Typically dorsoventrally flattened.Always have 34 segments.Suckers at both ends.Leeches are common in warm protected waters of lakes, ponds, streams, and marshes.Leeches usually avoid light by hiding under rocks or among aquatic vegetation or detritus.Silty substrates are unsuitable for leeches because they cannot attach properly.
33 Aquatic Worm Measure 1-30 mm in length, but sometimes over 100 mm. Clear whitish to pink in color.Body consists of 7 to 500 segments.Segments often have bristles or hairs.Tolerant of low dissolved oxygen concentrations.Found in silty substrates and among debris or detritus in pods, lakes, streams and rivers.Dense populations of Tubificids can often be found in organically polluted rivers.Approximately 200 species in North America
34 Lunged SnailShell usually opens to the leftBreathe AirNo operculum
35 Calculate your results If you find: You may have: Variety of macroinvertebrates, lots of each kindHealthy StreamLittle variety, with many of each kindWater enriched with organic matterA variety of macroinvertebrates, but a few of each kind, or No macroinvertebrates but the stream appears cleanToxic pollutionFew macroinvertebrates and the streambed is covered with sedimentPoor habitat from sedimentation
36 “We monitor because we care; We care because we are informed; We are informed because we monitor.”-- Cassie Champion
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