Module 4 Stream Invertebrate Survey Interpretation

MAPLE CREEK | Survey ID: 183

A) Abundance and density

ABUNDANCE: 382 / NUMBER OF SAMPLES: (3 *.09) = DENSITY: 1,414.81

B) PREDOMINANT TAXON

Pouch Snail

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) = 3
2 x (# of category 2) = 4
(# of category 3) = 4
= 11

EPT INDEX
Good Acceptable Marginal Poor
greater than 8 5 - 8 2 - 5 0 - 1
Total number of EPT taxa from Column C = 3

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 21 / total 382 = 0.05

D) DIVERSITY ASSESSMENT

TOTAL NUMBER OF TAXA: 9

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 106 / 382 = 0.2984

SITE ASSESMENT RATING
Good Acceptable Marginal Poor
4 3 2 1
Pollution Tolerance Index: 2
EPT Index: 2
EPT to Total Ratio: 1
Predominant Taxon Ratio: 4
Total: 2.25

Field Data as Collected

Polution Tolerance

Number Counted

Number of Taxa

Common Name

Category 1 - Polution Intolerant 21 3 Caddisfly
Dobsonfly
Gilled Snail
Mayfly
Riffle Beetle
Stonefly
Water Penny
Sub Total: 21 3 1
Category 2 - Somewhat Pollution Tolerant Alderfly larva
Aquatic Beetle
23 1 Aquatic Sowbug
Clam, Mussel
Cranefly Larva
Crayfish
Damselfy Larva
Dragonfly Larva
Fishfly Larva
114 1 Scud
Watersnipe Larva
Sub Total: 137 2 2
Category 3 - Pollution Tolerant 104 1 Aquatic Worm
Blackfly Larva
Leech
3 1 Midge Larva (chironomid)
Planarian
106 1 Pouch Snail
Truebug Adult
11 1 Water Mite
Sub Total: 224 4 4
Total: 382 9 7