20080868 Ver 2_I-42 2017 PA2 Ponar Downstream Biotic Index Table_20180629

Table 1-42. Estuarine Biotic Index (EBI) calculations for benthic ponar samples at the PA2
downstream station in May 2017.
Species/taxon'
Number of
individualsb
Sensitivity
value (SV)`
Abundance Product of
value n) (SV)(n)
Annelida
Oligochaeta
Enchytraeidae sp.
1
1.0
1
1.0
Naididae sp. w/o hair
9
1.0
3
3.0
Tubificoides heterochaetus
13
1.1
10
11.0
Polychaeta
Amphicteis floridus
325
2.0
100
200.0
Eteone heteropoda
19
1.6
10
16.0
Marenzelleria vindis
470
2.6
100
260.0
Mediomastus ambiseta
24
2.0
10
20.0
Laeonereis culveri
39
1.0
30
30.0
Polydora cornuta
1
1.2
1
1.2
Streblospio benedecti
7
1.1
3
3.3
Arthropoda
Insecta
Coleoptera
Peltodytes sp.
1
1.4
1
1.4
Diptera
Dicrotendipes nervosus
3
1.0
3
3.0
Tanypus neopunctipennis
2
1.0
1
1.0
Tanytarsus sp.
3
2.3
3
6.9
Hemiptera
Corixidae sp.
13
1.3
10
13.0
Trichocorixa sexcincta
6
1.0
3
3.0
Odonata
Enallagma sp.
1
1.5
1
1.5
Malacostraca
Amphipoda
Apocorophium lacustre
1
2.2
1
2.2
Apocorophium louisianum
20
2.2
10
22.0
Apocorophium sp.
36
2.2
30
66.0
Gammarus tigrinus
23
2.0
10
20.0
Decapoda
Palaemonetes pugio
1
2.5
1
2.5
Isopoda
Cyathura polita
6
2.0
3
6.0
Edotia montosa
2
2.6
1
2.6
Tanaidacea
Hargeria rapax
2
1.6
1
1.6
Mollusca
Bivalvia
Macoma tenta
2
2.0
1
2.0
Rangia cuneata
11
1.0
10
10.0
Gastropoda
Littoridinops sp.
173
2.0
100
200.0
Total
458
910.2
Estuarine Biotic Index = 1.99
Total taxa = 27
Total taxa with sensitivitv values = 25
a Only those taxa for which a sensitivity value is available are displayed
b Total number of individuals caught in all five ponar replicates.
' Sensitivity values provided by NCDWR.
I-48