Module 4 Stream Invertebrate Survey Interpretation

HIUIHILL CREEK | Survey ID: 70

A) Abundance and density

ABUNDANCE: 288 / NUMBER OF SAMPLES: (2 *.09) = DENSITY: 1,600.00

B) PREDOMINANT TAXON

Mayfly Larva

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) = 12
2 x (# of category 2) = 4
(# of category 3) = 3
= 19

EPT INDEX
Good Acceptable Marginal Poor
greater than 8 5 - 8 2 - 5 0 - 1
Total number of EPT taxa from Column C = 20

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 270 / total 288 = 0.94

D) DIVERSITY ASSESSMENT

TOTAL NUMBER OF TAXA: 26

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 147 / 288 = 0.5104

SITE ASSESMENT RATING
Good Acceptable Marginal Poor
4 3 2 1
Pollution Tolerance Index: 3
EPT Index: 4
EPT to Total Ratio: 4
Predominant Taxon Ratio: 3
Total: 3.5

Field Data as Collected

Polution Tolerance

Number Counted

Number of Taxa

Common Name

Category 1 - Polution Intolerant 75 4 Caddisfly
Dobsonfly
Gilled Snail
147 9 Mayfly
3 1 Riffle Beetle
48 7 Stonefly
Water Penny
Sub Total: 273 21 4
Category 2 - Somewhat Pollution Tolerant Alderfly larva
6 1 Aquatic Beetle
Aquatic Sowbug
Clam, Mussel
1 1 Cranefly Larva
Crayfish
Damselfy Larva
Dragonfly Larva
Fishfly Larva
Scud
Watersnipe Larva
Sub Total: 7 2 2
Category 3 - Pollution Tolerant 1 1 Aquatic Worm
Blackfly Larva
Leech
3 1 Midge Larva (chironomid)
Planarian
Pouch Snail
Truebug Adult
4 1 Water Mite
Sub Total: 8 3 3
Total: 288 26 9