Module 4 Stream Invertebrate Survey Interpretation
Deer Lake, Nov 23, 2016 | Survey ID: 174
A) ABUNDANCE AND DENSITY
ABUNDANCE total number of organisms from Column B: 69
DENSITY invertebrate density per square meter
# of 30cm x 30cm samples: 2
(total # counted 69) / (# of 30cm x 30cm samples x.09m2 2 / (Area: 0.18)) : 383.33
B) PREDOMINANT TAXON: Scud, (29)
C) WATER QUALITY ASSESSMENTS
POLLUTION TOLERANT INDEX
Good Acceptable Marginal Poor
greater than 22 22 - 17 17 -11 less than 11
3 x (# of category 1) = 0
2 x (# of category 2) = 4
(# of category 3) = 4
Pollution Tolerant Index = 8
EPT INDEX
Good Acceptable Marginal Poor
greater than 8 5 - 8 2 - 5 0 - 2
Total number of EPT taxa from Column C = 0
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 0 / total 69 = 0.00
D) DIVERSITY ASSESSMENT
Total Number of Taxa: 8
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:
29 / 69 = 0.4203
SITE ASSESMENT RATING
Good Acceptable Marginal Poor
4 3 2 1
Pollution Tolerance Index: 1
EPT Index: 1
EPT to Total Ratio: 1
Predominant Taxon Ratio: 3
Total: 1.5

Field Data as Collected
Polution Tolerance
Number Counted
Number of Taxa
Common Name
Category 1 - Polution Intolerant Caddisfly
Dobsonfly
Gilled Snail
Mayfly
Riffle Beetle
Stonefly
Water Penny
Sub Total: 0 0
Category 2 - Somewhat Pollution Tolerant Alderfly larva
Aquatic Beetle
10 1 Aquatic Sowbug
Clam, Mussel
Cranefly Larva
Crayfish
Damselfy Larva
Dragonfly Larva
Fishfly Larva
29 1 Scud
Watersnipe Larva
Sub Total: 39 2
Category 3 - Pollution Tolerant 17 3 Aquatic Worm
Blackfly Larva
2 1 Leech
1 1 Midge Larva (chironomid)
10 1 Planarian
Pouch Snail
Truebug Adult
Water Mite
Sub Total: 30 6