20080868 Ver 2_I-9 2015 Drinkwater Sweep Upstream Biotic Index Table_20160708

Table 1-9. Estuarine Biotic Index (EBI) calculations for benthic sweep samples at the Drinkwater Creek upstream station in
May 2015.
Species/taxono
Number of
individualsb
Sensitivity
value (SV)`
Abundance
value n
Product of
(SV)(n)
Annelida
Oligochaeta
Tubificidae sp. w/o hair
8
1.0
3
3.0
Tubificoides heterochaetus
9
1.1
3
3.3
Polychaeta
Amphicteis floridus
96
2.0
30
60.0
Arthropoda
Insecta
Coleoptera
Berosus sp.
15
1.5
10
15.0
Diptera
Bezzia/Palpomyia complex
28
2.3
10
23.0
Chironomus decorus
44
1.0
30
30.0
Cricotopus sp.
2
1.4
1
1.4
Goeldichironomus devineyae
37
2.0
30
60.0
Parachironomus sp.
5
1.1
3
3.3
Tanypus neopunctipennis
2
1.0
1
1.0
Tanytarsus sp.
43
2.3
30
69.0
Hemiptera
Abedus/Belostoma sp.
15
1.0
10
10.0
Corixidae sp.
2
1.3
1
1.3
Trichocorixa sexcinta
2
1.0
1
1.0
Odonata
Enallagma sp.
15
1.5
10
15.0
Erythemis simplicicollis
2
1.0
1
1.0
Malacostraca
Amphipoda
Apocorophium louisianum
157
2.2
100
220.0
Apocorophium sp.
244
2.2
100
220.0
Gammarus tigrinus
300
2.0
100
200.0
Isopoda
Cassidinidea lunifrons
67
2.0
30
60.0
Cyathura polita
33
2.0
30
60.0
Mollusca
Bivalvia
Mytilopsis leucophaeata
14
1.5
10
15.0
Gastropoda
Littoridinops sp.
300
2.0
100
200.0
Total
644
1,272.3
Estuarine Biotic Index = 1.98
Total taxa = 22
Total taxa with sensitivitv values = 20
80nly those taxa for which a sensitivity value is available are displayed
bTotal number of individuals caught in all three sweep replicates.
Sensitivity values provided by NCDWR.
1-15