20080868 Ver 2_I-12 2015 Little Sweep Downstream Biotic Index Table_20160708

Table 1-12. Estuarine Biotic Index (EBI) calculations for benthic sweep samples at the Little Creek downstream station in
Mav 2015.
Species/taxon a
Number of
individualsb
Sensitivity
value (SV)'
Abundance
value n
Product of
(SV)(n)
Annelida
Oligochaeta
Tubificoides heterochaetus
11
1.1
10
11.0
Polychaeta
Amphicteis floridus
27
2.0
10
20.0
Marenzelleria viridis
1
2.6
1
2.6
Polydora cornuta
3
1.2
3
3.6
Arthropoda
Insecta
Diptera
Bezzia/Palpomyia complex
6
2.3
3
6.9
Chironomus decorus
10
1.0
10
10.0
Dicrotendipes nervosus
33
1.0
30
30.0
Goeldichironomus devineyae
1
2.0
1
2.0
Parachironomus sp.
14
1.1
10
11.0
Polypedilum sp.
1
1.5
1
1.5
Tanytarsus sp.
26
2.3
10
23.0
Hemiptera
Abedus/Belostoma sp.
1
1.0
1
1.0
Ranatra buenoi
1
2.6
1
2.6
Malacostraca
Apocorophium lacustre
44
2.2
30
66.0
Apocorophium louisianum
14
2.2
10
22.0
Apocorophium sp.
290
2.2
100
220.0
Gammarus mucronatus
5
2.3
3
6.9
Gammarus tigrinus
223
2.0
100
200.0
Decapoda
Palaemonetes pugio
14
2.5
10
25.0
Rhithropanopeus harrisii
141
2.5
100
250.0
Isopoda
Cassidinidea lunifrons
5
2.0
3
6.0
Cyathura polita
6
2.0
3
6.0
Edotia montosa
6
2.6
3
7.8
Mysida
Americamysis almyra
32
2.2
30
66.0
Tanaidacea
Hargeria rapax
8
1.6
3
4.8
Maxillopoda
Sessilia
Balanus improvisus
2
2.0
1
2.0
Mollusca
Bivalvia
Mytilopsis leucophaeata
24
1.5
10
15.0
Mulinia lateralis
2
2.3
1
2.3
Gastropoda
Littoridinops sp.
300
2.0
100
200.0
Total
598
1,225.0
Estuarine Biotic Index = 2.05
Total taxa = 33
Total taxa with sensitivitv values = 28
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.
1-18