20080868 Ver 2_I-50 2017 Little Ponar Downstream Biotic Index Table_20180629

Table 1-50. Estuarine Biotic Index (EBI) calculations for benthic ponar samples at the Little Creek
downstream station in May 2017.
Species/taxona
Number of
individualsb
Sensitivity
value (SV)`
Abundance Product of
value (n) (SV)(n)
Annelida
Oligochaeta
Tubificoides heterochaetus
5
1.1
3
3.3
Polychaeta
Amphicteis floridus
154
2.0
100
200.0
Eteone heteropda
10
1.6
10
16.0
Marenzelleria viridis
328
2.6
100
260.0
Mediomastus ambiseta
1
2.0
1
2.0
Polydora cornuta
3
1.2
3
3.6
Streblospio benedicti
106
1.1
100
110.0
Arthropoda
Insecta
Diptera
Bezzia/Palpomyia complex
3
2.3
3
6.9
Chironomus decorus
40
1.0
30
30.0
Tanypus neopunctipennis
12
1.0
10
10.0
Tanytarsus sp.
3
2.3
3
6.9
Malacostraca
Amphipoda
Apocorophium lacustre
166
2.2
100
220.0
Apocorophium sp.
162
2.2
100
220.0
Gammarus tigrinus
69
2.0
30
60.0
Isopoda
Cyathura polita
3
2.0
3
6.0
Edotia montosa
2
2.6
1
2.6
Mysida
Americamysis almyra
3
2.2
3
6.6
Mollusca
Bivalvia
Rangia cuneata
80
1.0
30
30.0
Gastropoda
Littoridinops sp.
18
2.0
10
20.0
Total
640
1,213.9
Estuarine Biotic Index = 1.90
Total taxa = 20
Total taxa with sensitivity values = 18
a Only those taxa for which a sensitivity value is available are displayed.
bTotal number of individuals caught in all five ponar replicates.
° Sensitivity values provided by NCDWR.
1-56