benthic macroinvertebrates

Extreme Benthics Extreme Benthics AcademyAcademy

““Benthic Macroinvertebrates 101”Benthic Macroinvertebrates 101”

What are Benthic What are Benthic Macroinvertebrates?Macroinvertebrates?

Benthic = bottom dwellingBenthic = bottom dwelling

Macro = large enough to see with the naked eyeMacro = large enough to see with the naked eye

Invertebrate = without a backbone (could be a clam, a worm, a Invertebrate = without a backbone (could be a clam, a worm, a crab, or an insect, for example)crab, or an insect, for example)

Often refer to them as “stream bugs”

Big Diversity of Benthic Big Diversity of Benthic MacroinvertebratesMacroinvertebrates

Leech

Black fly larva

Midge

Dragonfly

CrawdadCranefly Mosquito

CaddisflyMayfly

Stonefly

Gilled snail

Why Do We Monitor Why Do We Monitor Stream Bugs?Stream Bugs?

Chemical WQ data offers good, but limited Chemical WQ data offers good, but limited information.information. Only a “snapshot” view of conditionsOnly a “snapshot” view of conditions Doesn’t measure “biology”Doesn’t measure “biology”

NitratespH D.O.

Fecal coliform

Temperature T.S.S

Biological Biological AssessmentAssessment

Use living organisms to tell us something Use living organisms to tell us something about the environmentabout the environment

Why Use “stream bugs” in Why Use “stream bugs” in Bioassessment of StreamsBioassessment of Streams

AbundantAbundant

DiverseDiverse

SedentarySedentary

Stream Bugs = excellent indicator Stream Bugs = excellent indicator of the stream’s of the stream’s biologicalbiological health. health.

Populations reflect Populations reflect cumulativecumulative impacts . impacts .

They are easy to sample.They are easy to sample.

They have the same habitat needs as salmon .They have the same habitat needs as salmon .

Habitat Needs for Salmon and Habitat Needs for Salmon and Stream Bugs:Stream Bugs:

Clean, cold, oxygenated waterClean, cold, oxygenated water Connected migration pathsConnected migration paths Habitat features for spawning and features for spawning and

rearingrearing Dependable stream flows stream flows

Habitat Features for Spawning and Habitat Features for Spawning and RearingRearing

Dependable Stream FlowDependable Stream Flow

High FlowsHigh Flows

Smothered Salmon Eggs

Stream Bugs Stream Bugs Tell A StoryTell A Story

No “good” or “bad” bugsNo “good” or “bad” bugs

Presence or absence indicates healthPresence or absence indicates health

Diversity (not total number of bugs) = Healthier Diversity (not total number of bugs) = Healthier samplesample

How Do They Tell The Story?How Do They Tell The Story?

B.I.B.I.B.I.B.I.

““Benthic Index of Biological Integrity”Benthic Index of Biological Integrity”

10 “metrics” indicating stream health10 “metrics” indicating stream health

10 Metrics10 Metrics Taxa richnessTaxa richness # mayfly taxa (Ephemeroptera)# mayfly taxa (Ephemeroptera) # stonefly taxa (Plecoptera)# stonefly taxa (Plecoptera) # caddisfly taxa (Trichoptera)# caddisfly taxa (Trichoptera) # long-lived taxa# long-lived taxa # intolerant taxa# intolerant taxa % tolerant taxa% tolerant taxa % predators% predators # clinger taxa# clinger taxa % dominance (3 taxa)% dominance (3 taxa)

Mayfly larva

Stonefly larva

Caddisfly larva

Caddisfly case

Taxa RichnessTaxa Richness

Leech

Black fly larva

Midge

Dragonfly

CrawdadCranefly Mosquito

CaddisflyMayfly

Stonefly

Gilled snail

% Dominance (3 taxa)% Dominance (3 taxa)

Ephemeroptera

Plecoptera

Trichoptera

leech

bloodworm

netspinner caddisfly

Intolerant speciesTolerant species

Plecoptera

Number of Intolerant TaxaNumber of Intolerant Taxalepidostomatidae caddisfly

ephemerellidae mayfly nymphcapniidae stonefly nymph

Gilled snailDobsonfly larva

Riffle beetle

Water penny

% Tolerant Taxa% Tolerant Taxa

leech

black fly larva

bloodworm

netspinner caddisflybaetidae mayflies

Midge larva

Number of Clinger TaxaNumber of Clinger TaxaWater penny

Stonefly nymph Mayfly nymph

Caddisfly larvae – Caddisfly

Alderfly

Riffle beetle larva

Number of Long-Lived TaxaNumber of Long-Lived Taxa

Dragonfly nymph

Alderfly larva Gilled snail

Pteronarcys stonefly

Dragonfly nymph

Number of Mayfly TaxaNumber of Mayfly Taxa(Ephemeroptera)(Ephemeroptera)

Number of Caddisfly TaxaNumber of Caddisfly Taxa(Trichoptera)(Trichoptera)

Number of Stonefly TaxaNumber of Stonefly Taxa(Plecoptera)(Plecoptera)

% Predators taxa% Predators taxa

water beetle

Dragonfly larva

Great diving beetle

Stonefly larva

Rhycophila caddisfly

Computing the B.I.B.I.Computing the B.I.B.I. Example: Taxa RichnessExample: Taxa Richness

0-20 taxa = low (0-20 taxa = low (11)) 21-40 taxa = moderate (21-40 taxa = moderate (33)) 40+ taxa = high (40+ taxa = high (55))

Computing the B.I.B.I.Computing the B.I.B.I. Taxa richnessTaxa richness 1 1 33 5 5 # mayfly taxa (Ephemeroptera)# mayfly taxa (Ephemeroptera) 1 3 1 3 55 # stonefly taxa (Plecoptera)# stonefly taxa (Plecoptera) 1 1 33 5 5 # caddisfly taxa (Trichoptera)# caddisfly taxa (Trichoptera) 11 3 5 3 5 # long-lived taxa# long-lived taxa 11 3 5 3 5 # intolerant taxa# intolerant taxa 1 1 33 5 5 % tolerant taxa% tolerant taxa 11 3 5 3 5 % predators% predators 1 1 33 5 5 # clinger taxa# clinger taxa 1 3 1 3 55 % dominance (3 taxa)% dominance (3 taxa) 1 3 1 3 55

Computing the B.I.B.I.Computing the B.I.B.I. Taxa richnessTaxa richness 33 # mayfly taxa (Ephemeroptera)# mayfly taxa (Ephemeroptera) 55 # stonefly taxa (Plecoptera)# stonefly taxa (Plecoptera) 33 # caddisfly taxa (Trichoptera)# caddisfly taxa (Trichoptera) 11 # long-lived taxa# long-lived taxa 11 # intolerant taxa# intolerant taxa 33 % tolerant taxa% tolerant taxa 11 % predators% predators 33 # clinger taxa# clinger taxa 55 % dominance (3 taxa)% dominance (3 taxa) 55 TOTAL:TOTAL: 30 30

Final B.I.B.I. Scores*Final B.I.B.I. Scores*

10 – 16 = Very Poor10 – 16 = Very Poor 18 - 26 = Poor18 - 26 = Poor 28 – 36 = Fair28 – 36 = Fair 38 – 44 = Good38 – 44 = Good 46 - 50 = Excellent46 - 50 = Excellent

*10 Metric B-IBI Score used by Mindy Allen*10 Metric B-IBI Score used by Mindy Allen

Stonefly

Caddisfly

When in the Field….When in the Field….

Observe: land use, canopy cover…etc.