20080868 Ver 2_I-11 2017 Little Sweep Upstream Biotic Index Table_20180629

Table 1-11. Estuarine Biotic Index (EBI) calculations for benthic sweep samples at the Little Creek upstream station in May
2017.
Species/taxona
Number of
individualsb
Sensitivity
value (SV)'
Abundance
value n
Product of
(SV)(n)
Annelida
Oligochaeta
Limnodrilus hoffineisteri
13
1.0
10
10.0
Naididae sp. w/o hair
73
1.0
30
30.0
Paranais sp.
15
1.1
10
11.0
Polychaeta
Amphicteis floridus
7
2.0
3
6.0
Arthropoda
Insecta
Coleptera
Peltodytes sp.
5
1.4
3
4.2
Tropisternus blatchleyi
2
1.0
1
1.0
Diptera
Bezzia/Palpomyia complex
34
2.3
30
69.0
Chironomus decorus
163
1.0
100
100.0
Dicrotendipes nervosus
8
1.0
3
3.0
Glyptotendipes sp.
1
1.3
1
1.3
Goeldichironomus devineyae
5
2.0
3
6.0
Tanypus neopunctipennis
24
1.0
10
10.0
Tanytarsus sp.
15
2.3
10
23.0
Ephemeroptera
Callibaetis sp.
1
1.1
1
1.1
Hemiptera
Corixidae sp.
14
1.3
10
13.0
Pelocoris femoratus
2
2.3
1
2.3
Ranatra nigra
1
2.6
1
2.6
Ranatra sp.
1
2.6
1
2.6
Malacostraca
Amphipoda
Gammarus tigrinus
300
2.0
100
200.0
Decapoda
Procambarus sp.
2
1.7
1
1.7
Isopoda
Cassidinidea lunifrons
10
2.0
10
20.0
Mollusca
Bivalvia
Mytilopsis leucophaeata
4
1.5
3
4.5
Rangia cuneata
1
1.0
1
1.0
Gastropoda
Littoridinops sp.
120
2.0
100
200.0
Physidae sp. (physa/physella)
100
1.3
100
130.0
Total
543
853.3
Estuarine Biotic Index = 1.57
Total taxa = 29
Total taxa with sensitivitv values = 22
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.
1-15