20080868 Ver 2_I-10 2017 Drinkwater Sweep Downstream Biotic Index Table_20180629

Table 1-10. Estuarine Biotic Index (EBI) calculations for benthic sweep samples at the Drinkwater Creek downstream
station in Mav 2017.
Species/taxon a
Number of
individualsb
Sensitivity
value (TV)'
Abundance
value n
Product of
(TV)(n)
Annelida
Polychaeta
Amphicteis floridus
22
2.0
10
20.0
Marenzelleria viridis
2
2.6
1
2.6
Polydora cornuta
8
1.2
3
3.6
Arthropoda
Insecta
Diptera
Apedilum sp.
1
4.0
1
4.0
Bezzia/Palpomyia complex
4
2.3
3
6.9
Dicrotendipes nervosus
54
1.0
30
30.0
Goeldichironomus devineyae
2
2.0
1
2.0
Parachironomus sp.
36
1.1
30
33.0
Procladius sp.
2
1.2
1
1.2
Tanytarsus sp.
8
2.3
3
6.9
Hemiptera
Corixidae sp.
13
1.3
10
13.0
Trichocorixa sexcinta
18
1.0
10
10.0
Odonata
Enallagma sp.
4
1.5
3
4.5
Malacostraca
Amphipoda
Apocorophium lacustre
174
2.2
100
220.0
Apocophorium louisianum
4
2.2
3
6.6
Apocorophium sp.
215
2.2
100
220.0
Gammarus mucronatus
4
2.3
3
6.9
Gammarus tigrinus
276
2.0
100
200.0
Uhlorchestia uhleri
2
2.0
1
2.0
Decapoda
Palaemonetes pugio
6
2.5
3
7.5
Isopoda
Cassidinidea lunifrons
30
2.0
30
60.0
Cyathura polity
11
2.0
10
20.0
Edotia montosa
4
2.6
3
7.8
Tanaidacea
Hargeria rapax
116
1.6
100
160.0
Maxillopoda
Sessilia
Balanus improvisus
3
2.0
3
6.0
Mollusca
Bivalvia
Mytilopsis leucophaeata
4
1.5
3
4.5
Gastropoda
Littoridinops sp.
300
2.0
100
200.0
Total
1
665
1,259.0
Estuarine Biotic Index = 1.89
Total taxa = 30
Total taxa with sensitivitv values = 25
'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.
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