20080868 Ver 2_I-38 2015 Jacobs Ponar Downstream Biotic Index Table_20160708

Table 1-38. Estuarine Biotic Index (EBI) calculations for benthic ponar samples at the Jacobs Creek
downstream station in May 2015.
Species/taxon'
Number of
individualsb
Sensitivity
value (SV)`
Abundance
value (n)
Product of
(SV)(n)
Annelida
Oligochaeta
Tubificidae sp. w/o hair
4
1.0
3
3.0
Polychaeta
Amphicteis floridus
4
2.0
3
6.0
Eteone heteropoda
20
1.6
10
16.0
Heteromastus filiformis
1
1.1
1
1.1
Marenzellaria viridis
3
2.6
3
7.8
Mediomastus ambiseta
6
2.0
3
6.0
Streblospio benedicti
33
1.1
30
33.0
Arthropoda
Insecta
Diptera
Bezzia/Palmonyia sp.
1
2.3
1
2.3
Chironomus decorus
443
1.0
100
100.0
Parachironomus sp.
3
1.1
3
3.3
Tanypus neopunctipennis
12
1.0
10
10.0
Tanytarsus sp.
18
2.3
10
23.0
Malacostraca
Amphipoda
Apocorophium lacustre
4
2.2
3
6.6
Apocorophium sp.
8
2.2
3
6.6
Gammarus mucronatus
7
2.3
3
6.9
Gammarus tigrinus
58
2.0
30
60.0
Isopoda
Edotia montosa
5
2.6
3
7.8
Mysida
Americamysis almyra
8
2.2
3
6.6
Tanaidacea
Hargeria rapax
1
1.6
1
1.6
Mollusca
Bivalvia
Macoma balthica
12
1.5
10
15.0
Macoma tenta
10
2.0
10
20.0
Gastropoda
Littoridinops sp.
16
2.0
10
20.0
Total
253
362.6
Estuarine Biotic Index = 1.43
Total taxa = 23
Total taxa with sensitivity values = 21
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.