Intro to MacroinvertebratesIntro to Macroinvertebrates

Aquatic EcologyAquatic EcologyDave WernerDave Werner

MATESMATES

Biological MonitoringBiological Monitoring Biological monitoring involves collecting, identifying Biological monitoring involves collecting, identifying

and counting macroinvertebratesand counting macroinvertebrates

The purpose of biological monitoring is to quickly The purpose of biological monitoring is to quickly assess both assess both water and habitat qualitywater and habitat quality

Healthy streams are characterized by Healthy streams are characterized by abundant abundant and diverseand diverse macroinvertebrate populations macroinvertebrate populations (however our key places importance on (however our key places importance on diversediverse populations)populations)

Monitoring involves Monitoring involves quarterly samplingquarterly sampling by by volunteersvolunteers

Macros are organisms that lack a backbone and can be seen Macros are organisms that lack a backbone and can be seen with the naked eye such as aquatic insects, mollusks and with the naked eye such as aquatic insects, mollusks and crustaceanscrustaceans

The organisms that we will be sampling for are benthic The organisms that we will be sampling for are benthic macroinvertebrates – macros that live in the substrate, or macroinvertebrates – macros that live in the substrate, or bottom, of a water bodybottom, of a water body

Macros live in various stream habitats and Macros live in various stream habitats and derive their oxygen derive their oxygen from the waterfrom the water

These organisms are impacted by all the stresses that occur in a These organisms are impacted by all the stresses that occur in a stream environment, both man-made and naturally occurringstream environment, both man-made and naturally occurring

What are Macroinvertebrates?What are Macroinvertebrates?

Macroinvertebrates asMacroinvertebrates as Indicators of Water Quality Indicators of Water Quality

NotNot very mobile very mobile

Present during ALL stream events (though recent Present during ALL stream events (though recent heavy rainsheavy rains can affect resultscan affect results))

Relatively easy to catch, view and identifyRelatively easy to catch, view and identify

They are affected by the physical, chemical and They are affected by the physical, chemical and biological conditions of the streambiological conditions of the stream

Values may Values may differ upon locationdiffer upon location

Benthic macroinvertebrates

• Benthic = Live on or in bottom substrate

• Macro = Large enough to be seen with unaided eye

• Invertebrate = Animal without a backbone

Why study macroinvertebrates?

• Affected by the physical, chemical and biological conditions of stream

• Can’t escape pollution - show the effects of short and long-term pollution events

• Can show the cumulative impacts of pollution

• May show the impacts of habitat loss

Why study macroinvertebrates?

• Critical part of the stream’s food web

• Relatively easy to sample and identify (easier than algae)

• Have greater diversity in stream than fish - sport fishing, stocking of fish and exotic species have altered fish community

IDENTIFICATION

Key identification features

• Overall body shape (NOT SIZE)• Case made of sticks, leaves, stone• Legs• Presence and location of gills• Presence and location of cerci (“tails”)• Head capsule, unusual appendages• Movement (crawl; swim side-to-side, up-down)

Body shape

Case

Legs and prolegs

Caddis removed from case

Prolegs on midge

Gills

Mayfly (Speckle-Winged Quill, Callibaetis)

Cerci (tails)

Baetis has center tail that is ½ length of outer tails

Head capsule

When and how often?When and how often?

Because aquatic biological communities are Because aquatic biological communities are relatively stable over time, plan on monitoring:relatively stable over time, plan on monitoring:

Once every Once every 3 months, season or quarter3 months, season or quarter

Same time and locationSame time and location

Record weather conditionsRecord weather conditions

Stream HabitatsStream Habitats RifflesRiffles - shallow area of a stream in which water - shallow area of a stream in which water

flows rapidly over a rocky or gravelly stream bed flows rapidly over a rocky or gravelly stream bed

Leaf packsLeaf packs - decomposing vegetation that is - decomposing vegetation that is submerged in the watersubmerged in the water

Vegetated marginsVegetated margins - area along the edge of water - area along the edge of water body consisting of overhanging bank vegetationbody consisting of overhanging bank vegetation

Woody debrisWoody debris - dead or living trees, roots, limbs, or - dead or living trees, roots, limbs, or other submerged organic matter other submerged organic matter

Sand/rock/gravel streambedSand/rock/gravel streambed - area of stream with - area of stream with coarse substratecoarse substrate

Stream Types and Sampling Stream Types and Sampling LocationsLocations

Rocky Bottom StreamsRocky Bottom Streams Generally found in Northern NJGenerally found in Northern NJ Characterized by fast moving water flowing over Characterized by fast moving water flowing over

large rocks and boulderslarge rocks and boulders Stream stretch consist of pool/riffle systemStream stretch consist of pool/riffle system

Muddy Bottom StreamsMuddy Bottom Streams Found mostly in Southern NJ and urban Found mostly in Southern NJ and urban

environments due to erosion and sedimentationenvironments due to erosion and sedimentation Slow moving water with little or no turbulenceSlow moving water with little or no turbulence Substrate is generally composed of fine silt, sand Substrate is generally composed of fine silt, sand

or coarse gravelor coarse gravel

Rocky Bottom Sampling MethodRocky Bottom Sampling Method

3 Riffle areas3 Riffle areas Sample 2x2 foot area with kick seine netSample 2x2 foot area with kick seine net

4 Leaf packs4 Leaf packs Take 20g of leavesTake 20g of leaves

Muddy Bottom Sampling MethodMuddy Bottom Sampling Method

Vegetative Margins Vegetative Margins 7 scoops (1 square foot)7 scoops (1 square foot)

Woody Debris with organic matterWoody Debris with organic matter 4 scoops (1 square foot)4 scoops (1 square foot)

Sand/rock/gravel or coarsest area of streambedSand/rock/gravel or coarsest area of streambed 3 scoops (1 square foot)3 scoops (1 square foot)

Sample 3 different habitats using D-frame netSample 3 different habitats using D-frame net

Calculate Your ResultsCalculate Your Results

• To calculate the results of your macroinvertebrate To calculate the results of your macroinvertebrate sampling use the forms in the field manualsampling use the forms in the field manual

• These forms calculate the water quality rating based These forms calculate the water quality rating based on the abundance, and on the abundance, and more importantly, the more importantly, the diversitydiversity of benthic macroinvertebrates found of benthic macroinvertebrates found

• Pollution Tolerance IndexPollution Tolerance Index

After Calculating Your Results…After Calculating Your Results…If you find:If you find:

A variety of macroinvertebrates, A variety of macroinvertebrates, lots of each kindlots of each kind

Little variety, with many of each Little variety, with many of each kindkind

A variety of macroinvertebrates, A variety of macroinvertebrates, but a few of each kind, orbut a few of each kind, or No No macroinvertebrates but the stream macroinvertebrates but the stream appears cleanappears clean

Few macroinvertebrates and the Few macroinvertebrates and the streambed is covered with streambed is covered with sedimentsediment

You may have:You may have:

Healthy streamHealthy stream

Water enriched with organic Water enriched with organic mattermatter

Toxic pollutionToxic pollution

Poor habitat from Poor habitat from sedimentationsedimentation

Group 1 TaxaGroup 1 Taxa

Pollution Sensitive Organisms Pollution Sensitive Organisms Require High Levels of Dissolved OxygenRequire High Levels of Dissolved Oxygen

Found In Good Quality WaterFound In Good Quality Water

STONEFLY NYMPHSTONEFLY NYMPH

Measure Measure 11//2 2 -1-111//2 2 inch in inch in

length (not including tails)length (not including tails)

2 sets of wing pads 2 sets of wing pads

Branched gills betweenBranched gills between legs on underside of bodylegs on underside of body

Yellow to brown in colorYellow to brown in color Two claws on each foot

Two hair-like tails

MAYFLY NYMPHMAYFLY NYMPH

Mature larvae measure up to Mature larvae measure up to 33//44 inch in length (excluding tails) inch in length (excluding tails)

Two rows of long hairs present on inside of front legs, used for Two rows of long hairs present on inside of front legs, used for filtering food particles from the water. filtering food particles from the water.

Slender antennae Slender antennae

May be minnow like with a vertically oriented head and three tails May be minnow like with a vertically oriented head and three tails (as pictured) or may be more flattened with a horizontally oriented (as pictured) or may be more flattened with a horizontally oriented head and two tails. head and two tails.

One claw on each foot

Gills on abdomen

Usually three

hair-like tails

CADDISFLY NYMPHCADDISFLY NYMPH

Up to one inch in length Up to one inch in length

Antennae reduced and inconspicuousAntennae reduced and inconspicuous Curls up slightly (not as tightly as the Curls up slightly (not as tightly as the

common net-spinning caddisfly)common net-spinning caddisfly)

Three pairs of legs Two claws at posterior end

Aquatic Snipe Fly LarvaAquatic Snipe Fly Larva

Measure ¼ -1 inches in lengthMeasure ¼ -1 inches in length

Mostly cylindrical, with the front tapering to a cone-shaped pointMostly cylindrical, with the front tapering to a cone-shaped point

Body is pale brown to green colorBody is pale brown to green color

Larva have a number of mostly paired caterpillar-like prolegsLarva have a number of mostly paired caterpillar-like prolegs

Two stout, pointed tails with feathery hairs at back endTwo stout, pointed tails with feathery hairs at back end

Paired, caterpillar-like prolegs

Two pointed tails with feathery hairs at back endFront of body

tapered to a point

WATER PENNYWATER PENNY

Measures 1/4 inch in length

Flat disk-like body

Head and legs concealed from above

6 legs and branched gills on underside

Prefers cold running water

Water 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

RIFFLE BEETLERIFFLE BEETLE

Riffle beetles measure approximately Riffle beetles measure approximately

11//1616 to to 11//44 inch in length inch in length

Body small, usually oval Body small, usually oval

Legs are long Legs are long

Antennae are usually slender Antennae are usually slender

Riffle beetles walk slowly underwater. Riffle beetles walk slowly underwater.

They do not swim on the surface.They do not swim on the surface.

GILLED SNAILGILLED SNAIL

Shell usually opens on right Shell usually opens on right

Shell opening covered by a Shell opening covered by a thin plate (operculum) thin plate (operculum)

When monitoring, do not When monitoring, do not count empty shellscount empty shells!

Group 2 TaxaGroup 2 Taxa

Somewhat Pollution Tolerant OrganismsSomewhat Pollution Tolerant OrganismsRequire Moderate Levels of Dissolved OxygenRequire Moderate Levels of Dissolved Oxygen

Found In Good or Fair Quality Water Found In Good or Fair Quality Water

COMMON NET SPINNING COMMON NET SPINNING CADDISFLY LARVACADDISFLY LARVA

Branched gills along underside of body

Dorsal plates (sclerites) on all three thoracic segments

Bristle-like tuft at the end of the abdomen

Body is caterpillar-like with Body is caterpillar-like with three pairs of legs three pairs of legs

Body is strongly curved Body is strongly curved

DOBSONFLY & DOBSONFLY & FISHFLY LARVA FISHFLY LARVA

Abdomen terminates in two small prolegs, each bearing two claws. Abdomen terminates in two small prolegs, each bearing two claws.

Feeds on other aquatic insects. Feeds on other aquatic insects.

Dobsonflies (hellgrammites) are usually found on the underside of large Dobsonflies (hellgrammites) are usually found on the underside of large rocks in cool, slow-moving streams. rocks in cool, slow-moving streams.

Handle Dobsonflies (hellgrammites) carefully - larger individuals may Handle Dobsonflies (hellgrammites) carefully - larger individuals may deliver a painful pinch! deliver a painful pinch!

Measure 3/4 - 4 inches in length. Measure 3/4 - 4 inches in length.

Body is elongate and somewhat Body is elongate and somewhat flattened.flattened.

Short inconspicuous antennae.Short inconspicuous antennae.

Large pinching jaws

Paired cotton-like gill tufts

Eight pairs of lateral appendages

DRAGONFLY LARVADRAGONFLY LARVALarge eyes, large jaw that covers the underside

of head

Stocky body without tails

Measure ½ - 1 inch in length Measure ½ - 1 inch in length Abdomen usually much more narrow and slender than that of Abdomen usually much more narrow and slender than that of

dragonflies dragonflies

DAMSELFLY LARVADAMSELFLY LARVALarge eyes,

large jaw that covers the

underside of head

Three oar-shaped tails (gills)

CRANEFLY LARVACRANEFLY LARVA

Measure 1/3-2 inches in lengthMeasure 1/3-2 inches in length

Plump caterpillar-like segmented bodyPlump caterpillar-like segmented body

Milky green to brown color Milky green to brown color

Finger-like projections (gills) at back end of body

Head is usually pulled back into the

front of the body

CRAYFISHCRAYFISH

Measure up to 6 inches in length Measure up to 6 inches in length

Resembles a small lobsterResembles a small lobster

Crayfish are usually active only at night. During the day they Crayfish are usually active only at night. During the day they hide in burrows or under rocks. hide in burrows or under rocks.

Crayfish are omnivorous, eating both plants and animals. Crayfish are omnivorous, eating both plants and animals.

Five pairs of legs

Large pinchers

AQUATIC SOWBUGAQUATIC SOWBUG

Measure 5-20 mm in length.Measure 5-20 mm in length.

Clear whitish to pink in color. Clear whitish to pink in color.

Dorsoventrally flattened (top to bottom). Dorsoventrally flattened (top to bottom).

Seven pairs of legs, the first two are modified for grasping. Seven pairs of legs, the first two are modified for grasping.

Found in shallow freshwater on rocks or detritus. Found in shallow freshwater on rocks or detritus.

SCUDSCUD

Measure 5-20 mm in length. Measure 5-20 mm in length.

Clear whitish to pink in color. Clear whitish to pink in color.

Laterally flattened (side to side). Laterally flattened (side to side).

Found in shallow freshwater springs, streams, lakes and ponds.Found in shallow freshwater springs, streams, lakes and ponds.

Most species feed on detritus. Most species feed on detritus.

Scuds are an important food source for many fishes. Scuds are an important food source for many fishes.

CLAMS & MUSSELSCLAMS & MUSSELS

Clam Mussel

Fleshy body enclosed between two clamped shellsFleshy body enclosed between two clamped shells

If alive, shells cannot be pried apartIf alive, shells cannot be pried apart

When monitoring, do not count empty shellsWhen monitoring, do not count empty shells

Group 3 TaxaGroup 3 Taxa

Pollution Tolerant Organisms Pollution Tolerant Organisms Require Low Levels of Dissolved OxygenRequire Low Levels of Dissolved Oxygen

Found In Any Quality WaterFound In Any Quality Water

MIDGEFLY LARVAMIDGEFLY LARVA

Has a distinct head and two small prolegs at the front of the body

BLACKFLY LARVABLACKFLY LARVA

Measure to 1/2 inch in length Measure to 1/2 inch in length

Abdomen terminates in an attachment disc Abdomen terminates in an attachment disc

Blackfly larva prefer cold running water and are usually found Blackfly larva prefer cold running water and are usually found attached by the end of their abdomens to rocks, woody debris, attached by the end of their abdomens to rocks, woody debris, or vegetation in the currents of rivers and streamsor vegetation in the currents of rivers and streams

Head contains fan-like mouth brushes

Body is larger at the rear end, similar to a

bowling pin

LEECHLEECH

Measures 1.0 mm to 5.0 cm in length. Measures 1.0 mm to 5.0 cm in length.

Typically dorsoventrally flattened. Typically dorsoventrally flattened.

Leeches are common in warm protected waters of lakes, ponds, Leeches are common in warm protected waters of lakes, ponds, streams, and marshes. streams, and marshes.

Leeches usually avoid light by hiding under rocks or among aquatic Leeches usually avoid light by hiding under rocks or among aquatic vegetation or detritus. vegetation or detritus.

Silty substrates are unsuitable for leeches because they cannot Silty substrates are unsuitable for leeches because they cannot

attach properly.attach properly.

34 Segments

Suckers on both ends

AQUATIC WORMAQUATIC WORM

Measure 1-30 mm in length, Measure 1-30 mm in length,

but sometimes over 100 mm. but sometimes over 100 mm.

Clear whitish to pink in color. Clear whitish to pink in color.

Body consists of 7 to 500 segments. Body consists of 7 to 500 segments.

Segments often have bristles or hairs. Segments often have bristles or hairs.

Tolerant of low dissolved oxygen concentrations. Tolerant of low dissolved oxygen concentrations.

Found in silty substrates and among debris or detritus in ponds, lakes, Found in silty substrates and among debris or detritus in ponds, lakes, streams and rivers. streams and rivers.

Dense populations of Tubificids can often be found in organically Dense populations of Tubificids can often be found in organically polluted rivers. polluted rivers.

Approximately 200 species in North AmericaApproximately 200 species in North America

LUNGED SNAILSLUNGED SNAILS

Shell usually opens to the left when pointed end is upShell usually opens to the left when pointed end is up

Breathes airBreathes air

No operculumNo operculum

When monitoring, do not count empty shells!When monitoring, do not count empty shells!

Mosquito Larvae - Mosquito Larvae - VideoVideo

Organisms not part of Organisms not part of the PTIthe PTI

True BugsTrue Bugs Order Hemiptera – Giant Water Bugs, Water Order Hemiptera – Giant Water Bugs, Water

Scorpions, Water StridersScorpions, Water Striders Why are they not part of the PTI?Why are they not part of the PTI?