20080868 Ver 2_I-10 2015 Drinkwater Sweep Downstream Biotic Index Table_20160708

Table I-10. Estuarine Biotic Index (EBI) calculations for benthic sweep samples at the Drinkwater Creek downstream
station in Mav 2015.
Species/taxon'
Number of
individualsb
Sensitivity
value (TV)`
Abundance
value n
Product of
(TV)(n)
Annelida
Oligochaeta
Tubificidae sp. w/o hair
6
1.0
3
3.0
Polychaeta
Heteromastus filliformis
4
1.1
3
3.3
Laeonereis culveri
4
1.0
3
3.0
Polydora cornuta
2
1.2
1
1.2
Arthropoda
Insecta
Diptera
Bezzia/Palpomyia complex
4
2.3
3
6.9
Chironomus decorus
134
1.0
100
100.0
Dicrotendipes nervosus
37
1.0
30
30.0
Dolichopodidae sp.
2
1.0
1
1.0
Goeldichironomus devineyae
84
2.0
30
60.0
Parachironomus sp.
2
1.1
1
1.1
Tanytarsus sp.
122
2.3
100
230.0
Hemiptera
Abedus/Belostoma sp.
42
1.0
30
30.0
Corixidae sp.
2
1.3
1
1.3
Trichocorixa sexcinta
1
1.0
1
1.0
Odonata
Enallagma sp.
4
1.5
3
4.5
Malacostraca
Amphipoda
Apocorophium lacustre
116
2.2
100
220.0
Apocophorium louisianum
32
2.2
30
66.0
Apocorophium sp.
228
2.2
100
220.0
Gammarus mucronatus
78
2.3
30
69.0
Gammarus tigrinus
218
2.0
100
200.0
Decapoda
Palaemonetes pugio
10
2.5
10
25.0
Rhithropanopeus harrisii
12
2.5
10
25.0
Isopoda
Cassidinidea lunifrons
18
2.0
10
20.0
Cyathura polita
23
2.0
10
20.0
Edotia montosa
6
2.6
3
7.8
Tanaidacea
Hargeria rapax
207
1.6
100
160.0
Mollusca
Bivalvia
Geukensia demissa
1
3.4
1
3.4
Mytilopsis leucophaeata
11
1.5
10
15.0
Gastropoda
Littoridinops sp.
300
2.0
100
200.0
Total
1
924
1,727.5
Estuarine Biotic Index = 1.87
Total taxa = 32
Total taxa with sensitivitv values = 27
'Only 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.
1-16