20080868 Ver 2_I-70 2017 Porter Ponar Downstream Biotic Index Table_20180629

Table 1-70. Estuarine Biotic Index (EBI) calculations for benthic ponar samples at the Porter Creek
downstream station in May 2017.
Species/taxona
Number of
individualsb
Sensitivity
value (SV)`
Abundance
value (n)
Product of
(SV)(n)
Annelida
Polychaeta
Amphicteis floridus
170
2.0
100
200.0
Marenzelleria viridis
75
2.6
30
78.0
Polydora cornuta
14
1.2
10
12.0
Streblospio benedicti
150
1.1
100
110.0
Arthropoda
Insecta
Coleoptera
Berosus sp.
1
1.5
1
1.5
Diptera
Chironomus decorus
184
1.0
100
100.0
Coelotanypus sp.
2
1.8
1
1.8
Procladius sp.
22
1.2
10
12.0
Malacostraca
Amphipoda
Apocorophium lacustre
17
2.2
10
22.0
Apocorophium sp.
34
2.2
30
66.0
Gammarus tigrinus
28
2.0
10
20.0
Isopoda
Cyathura polity
1
2.0
1
2.0
Mollusca
Bivalvia
Rangia cuneata
23
1.0
10
10.0
Gastropoda
Littoridinops sp.
18
2.0
10
20.0
Total
423
655.3
Estuarine Biotic Index = 1.55
Total taxa = 14
Total taxa with sensitivity values = 13
a Only those taxa for which asSensitivity value is available are displayed
b Total number of individuals caught in all five pnar replicates.
° Sensitivity values provided by NCDWR.
1-76