20080868 Ver 2_I-48 2017 Little Ponar Upstream Biotic Index Table_20180629

Table 1-48. Estuarine Biotic Index (EBI) calculations for benthic ponar samples at the Little Creek
upstream station in May 2017.
Species/taxona
Number of
individualsb
Sensitivity
value (SV)`
Abundance Product of
value (n) (SV)(n)
Annelida
Oligochaeta
Limnodrilus hoffineisteri
41
1.0
30
30.0
Naididae sp. w/o hair
179
1.0
100
100.0
Paranais sp.
3
1.1
3
3.3
Tubificoides heterochaetus
36
1.1
30
33.0
Polychaeta
Amphicteis floridus
92
2.0
30
60.0
Arthropoda
Insecta
Diptera
Chironomus decorus
399
1.0
100
100.0
Clinotanypus sp.
3
1.4
3
4.2
Dicrotendipes nervosus
2
1.0
1
1.0
Procladius sp.
3
1.2
3
3.6
Tanypus neopunctipennis
13
1.0
10
10.0
Tanytarsus sp.
12
2.3
10
23.0
Malacostraca
Amphipoda
Apocorophium lacustre
3
2.2
3
6.6
Gammarus tigrinus
153
2.0
100
200.0
Mollusca
Bivalvia
Mytilopsis /eucophaeata
16
1.5
10
15.0
Gastropoda
Littoridinops sp.
17
2.0
10
20.0
Physidae sp. (physalphysella)
3
1.3
3
3.9
Total
446
613.6
Estuarine Biotic Index = 1.38
Total taxa = 18
Total taxa with sensitivity values = 15
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.
1-54