Stream Invertebrate Survey
Streamkeepers Handbook and Modules Module 4

Stream Location and Conditions

Stream Name/Nearest Town: Little Stawamus Creek/SquamishDate: August 29, 2001
Watershed Code:
Organization Name:Squamish StreamkeepersSteam Segment #
Stream Section #
Contact Person: Wendy Mitchell Phone # 604-986-5059
Sampler used, mesh size, total area sampled: D-net, 363 microns, .092 metres# of 30cm x 30cm samples: 1

Survey Location

~30m upstream from footbridge @ Cliffside Pub parking lot, Valleycliffe.

Time: 1:30 pm Weather:clear
Turbidity: greater than depth Temperature:Air: 210 Water: 120

Invertebrate Survey Field Data

COLUMN A COLUMN B COLUMN C COLUMN D
Pollution Tolerance Number Counted Number of Taxa Common Name
CATEGORY 1

(pollution
intolerant)
2 2Caddisfly Larva (EPT)
0 0Dobsonfly (hellgrammite)
0 0Gilled Snail
56 4Mayfly Nymph (EPT)
0 0Riffle Beetle
52 3Stonefly Nymph (EPT)
0 0Water Penny
Subtotal 110 9 Subtotal
CATEGORY 2

(somewhat tolerant
of pollution)
0 0Alderfly Larve
0 0Aquatic Beetle
0 0Aquatic Sowbug
0 0Clam, Mussel
2 1Cranefly Larva
0 0Crayfish
0 0Damselfly Larva
0 0Dragonfly Larva
0 0Fishfly Larva
0 0Scud
0 0Watersnipe Larva
Subtotal 2 1 Subtotal
CATEGORY 3

(pollution
tolerant)
4 2Aquatic Worm
22 1Blackfly Larva
0 0Leech
0 0Midge Larva (chironomid)
5 1Planarian
0 0Pouch and Pond Snails
0 0True Bug Adult
14 2Water Mite
Subtotal 45 6 Subtotal
TOTAL 157 16TOTAL

Invertebrate Survey Interpretation

A) Abundance and Density

From page 27 of Module 4 Invertebrate Survey in the Streamkeepers handbook and Modules
Abundance: 157
Density: 1744

B) Predominant Taxon: Mayfly

C) Water Quality Assessments:

Pollution Tolerant Index
Good Acceptable Marginal Poor
>22 22-17 16-11 greater than 11
Pollution Tolerance Index:
15 (marginal)
EPT Index
Good Acceptable Marginal Poor
>8 5-8 2-5 0-1
EPT Index:
9 (good)
EPT to Total Ratio
Good Acceptable Marginal Poor
0.75 - 1.00 0.50 - 0.75 0.25 - 0.50 0 - 0.25
EPT to Total Ratio:
.70 (acceptable)

D) Diversity Assessments:

Total Number of Taxa: 16
Predominant Taxon Ratio
Good Acceptable Marginal Poor
0 - .40 0.40 - 0.60 0.60 - 0.80 0.80 - 1.0
Predominant Taxon Ratio:
.36 (good)

E) Site Assessment Rating:

Site Assessment Rating
Good Acceptable Marginal Poor
0.75 - 1.00 0.50 - 0.75 0.25 - 0.50 0 - 0.25
Site Assement Rating
Index or Ratio Rating
Pollution Tolerance Index 2
EPT Index 4
EPT to Total Ratio 3
Predominant Taxon Ratio 4
Total 13
Average 3.25 (acceptable)
General Comments - Unknown Bugs
Temp increased to 190 in sorting tray (some inverts may have died before count).

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This page courtesy of The Pacific Streamkeepers Federation
October 01, 2001