Stream Invertebrate Survey
Streamkeepers Handbook and Modules Module 4

Stream Location and Conditions

Stream Name/Nearest Town: bridal Veil Falls/AgassizDate: August 28, 2001
Watershed Code:
Organization Name:The Pacific Streamkeepers FederationSteam Segment #
Stream Section #
Contact Person: Zo Ann Morten Phone # 604-986-5059
Sampler used, mesh size, total area sampled: serber, 363 microns, .272 metres# of 30cm x 30cm samples: 3

Survey Location

4 metres east of top parking lot at picnic/camp site.

Time: 6:00 pm Weather:clear

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)		 11 4Caddisfly Larva (EPT)
0 0Dobsonfly (hellgrammite)
0 0Gilled Snail
394 9Mayfly Nymph (EPT)
0 0Riffle Beetle
11 5Stonefly Nymph (EPT)
0 0Water Penny
Subtotal416 18Subtotal
CATEGORY 2

(somewhat tolerant
of pollution)		 0 0Alderfly Larve
0 0Aquatic Beetle
0 0Aquatic Sowbug
0 0Clam, Mussel
6 3Cranefly Larva
0 0Crayfish
0 0Damselfly Larva
0 0Dragonfly Larva
0 0Fishfly Larva
0 0Scud
0 0Watersnipe Larva
Subtotal6 3Subtotal
CATEGORY 3

(pollution
tolerant)		 4 2Aquatic Worm
0 0Blackfly Larva
0 0Leech
2 2Midge Larva (chironomid)
2 1Planarian
0 0Pouch and Pond Snails
0 0true Bug Adult
0 0Water Mite
Subtotal8 5Subtotal
TOTAL 430 26TOTAL

Invertebrate Survey Interpretation

A) Abundance and Density

From page 27 of Module 4 Invertebrate Survey in the Streamkeepers handbook and Modules
Abundance: 430
Density: 1593

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:
14 (marginal)
EPT Index
Good Acceptable Marginal Poor
>8 5-8 2-5 0-1
 EPT Index:
18 (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:
.97 (good)

D) Diversity Assessments:

Total Number of Taxa: 26
Predominant Taxon Ratio
Good Acceptable Marginal Poor
0 - .40 0.40 - 0.60 0.60 - 0.80 0.80 - 1.0
 Predominant Taxon Ratio:
.92 (poor)

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 4
Predominant Taxon Ratio 1
Total 11
Average 2.75 (marginal)
General Comments - Unknown Bugs
Mountain stream - downstream of waterfalls, just off parking lot for camp ground.

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