Module 4 Stream Invertebrate Survey Interpretation

ALOUETTE RIVER | Survey ID: 188

A) Abundance and density

ABUNDANCE: 84 / NUMBER OF SAMPLES: (1 *.09) = DENSITY: 933.33

B) PREDOMINANT TAXON

Aquatic Worm

C) WATER QUALITY ASSESSMENTS

POLLUTION TOLERANT INDEX
Good Acceptable Marginal Poor
greater than 22 22 - 17 16 - 11 less than 11
3 x (# of category 1) = 9
2 x (# of category 2) = 4
(# of category 3) = 5
= 18

EPT INDEX
Good Acceptable Marginal Poor
greater than 8 5 - 8 2 - 5 0 - 1
Total number of EPT taxa from Column C = 9

EPT TO TOTAL RATIO
Good Acceptable Marginal Poor
0.75 - 1.00 0.50 - 0.75 0.25 - 0.50 0 - 0.25
# of EPT 33 / total 84 = 0.39

D) DIVERSITY ASSESSMENT

TOTAL NUMBER OF TAXA: 18

PREDOMINANT TAXON RATIO
Good Acceptable Marginal Poor
0 - 0.40 0.40 - 0.60 0.60 - 0.80 0.80 - 1.0
PREDOMINANT TAXON RATIO: Predominant Taxa 28 / 84 = 0.3333

SITE ASSESMENT RATING
Good Acceptable Marginal Poor
4 3 2 1
Pollution Tolerance Index: 3
EPT Index: 4
EPT to Total Ratio: 2
Predominant Taxon Ratio: 4
Total: 3.25

Field Data as Collected

Polution Tolerance

Number Counted

Number of Taxa

Common Name

Category 1 - Polution Intolerant 1 1 Caddisfly
Dobsonfly
Gilled Snail
26 6 Mayfly
Riffle Beetle
6 2 Stonefly
Water Penny
Sub Total: 33 9 3
Category 2 - Somewhat Pollution Tolerant Alderfly larva
Aquatic Beetle
4 1 Aquatic Sowbug
Clam, Mussel
Cranefly Larva
Crayfish
Damselfy Larva
Dragonfly Larva
Fishfly Larva
4 1 Scud
Watersnipe Larva
Sub Total: 8 2 2
Category 3 - Pollution Tolerant 28 2 Aquatic Worm
5 1 Blackfly Larva
Leech
2 2 Midge Larva (chironomid)
3 1 Planarian
Pouch Snail
Truebug Adult
5 1 Water Mite
Sub Total: 43 7 5
Total: 84 18 10