20080868 Ver 2_I-21 2017 Porter Sweep Upstream Biotic Index Table_20180629

Table 1-21. Estuarine Biotic Index (EBI) calculations for benthic sweep samples at the Porter Creek upstream station in
May 2017.
Species/taxona
Number of
individualsb
Sensitivity
value (SV)`
Abundance
value (n)
Product of
(SV)(n)
Annelida
Oligochaeta
Naididae sp. w/o hair
8
1.0
3
3.0
Paranais sp.
1
1.1
1
1.1
Polychaeta
Amphicteis floridus
91
2.0
30
60.0
Arthropoda
Insecta
Coleoptera
Berosus sp.
4
1.5
3
4.5
Peltodytes sp.
4
1.4
3
4.2
Diptera
Bezzia/Palpomyia complex
4
2.3
3
6.9
Chironomus decorus
1
1.0
1
1.0
Cricotopus sp.
1
1.4
1
1.4
Dicrotendipes nervosus
9
1.0
3
3.0
Parachironomus sp.
2
1.1
1
1.1
Hemiptera
Abedus/Belostoma complex
24
1.0
10
10.0
Corixidae sp.
47
1.3
30
39.0
Libellula sp.
2
1.1
1
1.1
Pelocoris sp.
2
2.3
1
2.3
Ranatra nigra
2
2.6
1
2.6
Sigara sp.
1
1.4
1
1.4
Trichocorixa sexcintca
9
1.0
3
3.0
Odonata
Enallagma sp.
2
1.5
1
1.5
Malacostraca
Amphipoda
Apocorophium sp.
1
2.2
1
2.2
Gammarus tigrinus
300
2.0
100
200.0
Decapoda
Palaemonetes pugio
1
2.5
1
2.5
Isopoda
Cassidinidea lunifrons
79
2.0
30
60.0
Cyathura polita
5
2.0
3
6.0
Mysida
Americamysis almyra
1
2.2
1
2.2
Mollusca
Bivalvia
Mytilopsis leucophaeata
4
1.5
3
4.5
Gastropoda
Littoridinops sp.
258
2.0
100
200.0
Total
336
624.5
Estuarine Biotic Index = 1.86
Total taxa = 33
Total taxa with sensitivity values = 23
aOnly 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.
1-25