Module 4 Stream Invertebrate Survey Interpretation
BUCK CREEK | Survey ID: 257
A) Abundance and density
ABUNDANCE: 75 / NUMBER OF SAMPLES: (3 *.09) = DENSITY: 277.78
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) = 21
2 x (# of category 2) = 22
(# of category 3) = 8
= 51
EPT INDEX
Good
Acceptable
Marginal
Poor
greater than 8
5 - 8
2 - 5
0 - 1
Total number of EPT taxa from Column C = 10
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
51 / total
75 =
0.68
D) DIVERSITY ASSESSMENT
TOTAL NUMBER OF TAXA: 17
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 39 / 75 = 0.5200
SITE ASSESMENT RATING
Good
Acceptable
Marginal
Poor
4
3
2
1
Pollution Tolerance Index: 4
EPT Index: 4
EPT to Total Ratio: 3
Predominant Taxon Ratio: 3
Total: 3.5
POLLUTION TOLERANT INDEX | |||
---|---|---|---|
Good | Acceptable | Marginal | Poor |
greater than 22 | 22 - 17 | 16 - 11 | less than 11 |
3 x (# of category 1) = 21
2 x (# of category 2) = 22
(# of category 3) = 8
= 51
2 x (# of category 2) = 22
(# of category 3) = 8
= 51
EPT INDEX | |||
---|---|---|---|
Good | Acceptable | Marginal | Poor |
greater than 8 | 5 - 8 | 2 - 5 | 0 - 1 |
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
51 / total
75 =
0.68
PREDOMINANT TAXON RATIO | |||
---|---|---|---|
Good | Acceptable | Marginal | Poor |
0 - 0.40 | 0.40 - 0.60 | 0.60 - 0.80 | 0.80 - 1.0 |
SITE ASSESMENT RATING | |||
---|---|---|---|
Good | Acceptable | Marginal | Poor |
4 | 3 | 2 | 1 |
Pollution Tolerance Index: 4
EPT Index: 4
EPT to Total Ratio: 3
Predominant Taxon Ratio: 3
Total: 3.5
EPT Index: 4
EPT to Total Ratio: 3
Predominant Taxon Ratio: 3
Total: 3.5
Field Data as Collected
Polution Tolerance |
Number Counted | Number of Taxa | Common Name |
Category 1 - Polution Intolerant | 7 | 1 | Caddisfly |
0 | 0 | Dobsonfly | |
0 | 0 | Gilled Snail | |
39 | 7 | Mayfly | |
0 | 0 | Riffle Beetle | |
5 | 2 | Stonefly | |
0 | 0 | Water Penny | |
Sub Total: | 51 | 10 | 7 |
Category 2 - Somewhat Pollution Tolerant | 0 | 0 | Alderfly larva |
2 | 2 | Aquatic Beetle | |
0 | 0 | Aquatic Sowbug | |
0 | 0 | Clam, Mussel | |
0 | 0 | Cranefly Larva | |
0 | 0 | Crayfish | |
0 | 0 | Damselfy Larva | |
0 | 0 | Dragonfly Larva | |
0 | 0 | Fishfly Larva | |
0 | 0 | Scud | |
0 | 0 | Watersnipe Larva | |
Sub Total: | 2 | 2 | 11 |
Category 3 - Pollution Tolerant | 4 | 2 | Aquatic Worm |
0 | 0 | Blackfly Larva | |
0 | 0 | Leech | |
1 | 1 | Midge Larva (chironomid) | |
0 | 0 | Planarian | |
0 | 0 | Pouch Snail | |
0 | 0 | Truebug Adult | |
17 | 2 | Water Mite | |
Sub Total: | 22 | 5 | 8 |
Total: | 75 | 17 | 26 |