294
V. R. NAIR and T. S. S. RAo:
Table 1 (continued)
Species
Total abundance
Range of
Maximum observed density
Number Percentabundance
(No. per std. haul)
age
per 50 Sq.
SWmonsoon
NEmonsoon
I
('Yo)
S. hexaptera
6228
0.5
0-2.4
192
140
(off Somalia)
(off Somalia)
S. lyra
10 negligible negligible
10
(mouth of Gulf
of Aden)
S. minima
4837
0.4
0-10.5
800
500
(southwestern
(southwestern part at
part at 3 0 Slat.
8 0 S lat. and 54
0
E long.)
and 54 0 E long.)
S. neglecta
12 700
1.1
0-8.3
640
820
(off Arabia
(near Arabia towards
towards north)
north)
S. pacifica
119049 10.4
0.3-38.3
4400
2440
(near Arabia
(off Somalia)
towards north)
S. pulchra
5022
0.4
0-1.2
280
200
(near Somalia)
(Gulf of Aden and
off Somalia)
S. regularis
41495
3.6
0-17.1
1600
1004
(off Somalia)
(Gulf of Cam bay)
S. robusta
16774
1.5
0-8.3
730
606
(near Arabia
(off Somalia)
towards north)
S. zetesios
10 negligible negligible
10
(off Arabia towards north)
Table 2. Numerical abundance of the different epiplanktonic species of chaetognaths during the two
monsoon periods
Species
SWmonsoon
NEmonsoon
Total No. irreTotal
Average
Total
Average
specrive of seasons
No. per haul
No. per haul
K. pacifica
5481
23
5366
23
10 847
K. subtilis
2492
10
1288
6
3780
Pt. draco
27444
114
20875
92
48319
S. bedoti
45639
190
49070
217
94709
S. bipunctata
26068
109
22747
101
48815
S. enflata
371291
1547
326519
1445
697810
S. ferox
20395
85
3259
14
23654
S. hexaptera
3645
15
2583
11
6228
S. minima
3651
15
1186
5
4837
S. neglecta
5342
22
7358
33
12 700
S. pacifica
76622
319
42427
188
119049
S. pulchra
2179
9
2843
13
5022
S. regularis
27582
115
13913
88
41495
S. robusta
8721
36
8053
36
16774
Total:
626552
2609
507487
2272
1134039