Stream Invertebrate Survey
Streamkeepers Handbook and Modules Module 4


Get 2002 Data!!!!

Stream Location and Conditions

Stream Name/Nearest Town: Gravel Creek/HorseflyDate: August 30, 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, .092 metres# of 30cm x 30cm samples: 1

Survey Location

20m upstream of culvert under highway from 150 Mile House to Horsefly.

Time: 12:00 pm Weather:clear
Turbidity: greater than depth Temperature:Air: 14.50 Water: 140

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)		 58 5Caddisfly Larva (EPT)
0 0Dobsonfly (hellgrammite)
0 0Gilled Snail
303 7Mayfly Nymph (EPT)
4 2Riffle Beetle
8 2Stonefly Nymph (EPT)
0 0Water Penny
Subtotal 373 16 Subtotal
CATEGORY 2

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

(pollution
tolerant)		 0 0Aquatic Worm
15 1Blackfly Larva
0 0Leech
3 1Midge Larva (chironomid)
1 1Planarian
0 0Pouch and Pond Snails
0 0True Bug Adult
0 0Water Mite
Subtotal 19 3 Subtotal
TOTAL 393 20TOTAL

Invertebrate Survey Interpretation

A) Abundance and Density

From page 27 of Module 4 Invertebrate Survey in the Streamkeepers handbook and Modules
Abundance: 393
Density: 4366.66

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:
17 (acceptable)
EPT Index
Good Acceptable Marginal Poor
>8 5-8 2-5 0-1
 EPT Index:
14 (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:
.93 (good)

D) Diversity Assessments:

Total Number of Taxa: 20
Predominant Taxon Ratio
Good Acceptable Marginal Poor
0 - .40 0.40 - 0.60 0.60 - 0.80 0.80 - 1.0
 Predominant Taxon Ratio:
.77 (marginal)

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 3
EPT Index 4
EPT to Total Ratio 4
Predominant Taxon Ratio 2
Total 13
Average 3.25 (acceptable)
General Comments - Unknown Bugs
Most of the caddis had rock homes, stuck to the rocks. Creek runs through forested area near road. Stonefly casings found nearby.

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