20080868 Ver 2_I-6 2017 Jacobs Sweep Downstream Biotic Index Table_20180629

Table 1-6. Estuarine Biotic Index (EBI) calculations for benthic sweep samples at the Jacobs Creek downstream 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
1
1.0
1
1.0
Tubificoides heterochaetus
3
1.1
3
3.3
Polychaeta
Amphicteis floridus
46
2.0
30
60.0
Eteone heteropoda
9
1.6
3
4.8
Laeonereis culveri
2
1.0
1
1.0
Marenzellaria viridis
14
2.6
10
26.0
Polydora cornuta
6
1.2
3
3.6
Streblospio benedicti
1
1.1
1
1.1
Arthropoda
Insecta
Diptera
Chironomus decorus
38
1.0
30
30.0
Dicrotendipes nervosus
20
1.0
10
10.0
Goeldichironomus devineyae
11
2.0
10
20.0
Parachironomus sp.
9
1.1
3
3.3
Tanytarsus sp.
12
2.3
10
23.0
Hemiptera
Abedus/Belostoma complex
4
1.0
3
3.0
Corixidae sp.
126
1.3
100
130.0
Trichocorixa sexcintca
96
1.0
30
30.0
Odonata
Enallagma sp.
5
1.5
3
4.5
Ischnura sp.
4
1.0
3
3.0
Malacostraca
Amphipoda
Apocorophium lacustre
87
2.2
30
66.0
Apocorophium louisianum
1
2.2
1
2.2
Apocorophium sp.
274
2.2
100
220.0
Gammarus tigrinus
300
2.0
100
200.0
Decapoda
Palaemonetes pugio
6
2.5
3
7.5
Isopoda
Cassidinidea lunifrons
25
2.0
10
20.0
Cyathura polita
28
2.0
10
20.0
Edotia montosa
7
2.6
3
7.8
Maxillopoda
Sessilia
Balanus improvisus
5
2.0
3
6.0
Tanaidacea
Hargeria rapax
9
1.6
3
4.8
Mollusca
Bivalvia
Mytilopsis leucophaeata
4
1.5
3
4.5
Gastropoda
Littoridinops sp.
241
2.0
100
200.0
Total
620
1,116.4
Estuarine Biotic Index = 1.80
Total taxa = 32
Total taxa with sensitivity values = 27
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.
M