416
W. NELLEN:
Table 1. Arrangement and number of fish-larvae net hauls in the investigation area of "Meteor"
cruise during the lIOE
Area
Stations
Period
No. of
No. of
No. of
stat.
HLN
RT
fished
hauls
hauls
1964
southern part of Red Sea
44- 88
Nov. 30-Dec. 14
8
16
5
and inner part of
Gulf of Aden
Gulf of Aden profile
89- 98
Dec. 16 - Dec. 18
7
6
7
north of Cape Guardafui
99-109
Dec. 19 - Dec. 23
10
7
9
and profile No. III
profile No. IV
111-108
Dec. 24- Dec. 27
7
7
4
profile No. V
123-131
Dec. 28 - Dec. 31
8
8
4
1965
profile No. VI
132-139
Jan. I-Jan. 4
8
9
3
profile No. VII
141-150
Jan. 5-Jan.10
10
10
4
profile No. VIII plus
one shelf station
151-159
Jan. 11 - Jan. 15
9
9
3
profile No. IX
160-167
Jan. 22 - Jan. 24
7
9
3
profile No. X plus stations
168-181
Jan. 26 - Febr. 6
10
]4
8
in the open Arabian Sea
profile No. XI
182-190
Febr. 8-Febr.10
8
9
4
profile No. XII
193-202
Febr. 15 - Febr. 18
9
9
5
profile XIII
205 - 212
Febr. 20 - Febr. 26
8
7
4
profile No. XIV
213-221
Febr. 27 - Mar. 3
9
7
4
profile No. XV
222-230
Mar. 4 - Mar. 9
9
9
2
profile No. XVI
232-241
Mar. 11 - Mar. 13
8
11
NW profile into the
Gulf of Oman
242-249
Mar. 19- Mar. 24
8
15
Gulf of Oman
250-271
Mar. 24- Mar. 31
23
24
Gulf of Oman
379-368
Apr. 14-Apr. 16
Persian Gulf
272-378
Mar. 31- Apr. 14
65
41
30
231
227
99
west coast of India and Pakistan, where ostracods were dominant in the plankton, it was
necessary to add formalin to the plankton as soon as the catch carne on deck, as the
crustaceans severely damaged the delicate fish larvae by voracious feeding, even in the
bucket.
3. Variations in the Catch According to Net and Kind of Tow
The number of species caught per haul was generally lower in the HLN samples
than in the RT samples, and night catches were often more prolific than day catches.
In areas where a considerable number of HLN and RT day and night samples were
made, the mean difference between day and night is much more striking in the HLN
than in the RT tows. While the HLN samples showed a mean ratio for number of species
caught at night to number of species caught in daytime of 2.0, 2.5, and 3.8 in the three
areas, southern Red Sea to Gulf of Aden, Cape Guardafui to Mombasa, and the open
W. NELLEN:
Table 1. Arrangement and number of fish-larvae net hauls in the investigation area of "Meteor"
cruise during the lIOE
Area
Stations
Period
No. of
No. of
No. of
stat.
HLN
RT
fished
hauls
hauls
1964
southern part of Red Sea
44- 88
Nov. 30-Dec. 14
8
16
5
and inner part of
Gulf of Aden
Gulf of Aden profile
89- 98
Dec. 16 - Dec. 18
7
6
7
north of Cape Guardafui
99-109
Dec. 19 - Dec. 23
10
7
9
and profile No. III
profile No. IV
111-108
Dec. 24- Dec. 27
7
7
4
profile No. V
123-131
Dec. 28 - Dec. 31
8
8
4
1965
profile No. VI
132-139
Jan. I-Jan. 4
8
9
3
profile No. VII
141-150
Jan. 5-Jan.10
10
10
4
profile No. VIII plus
one shelf station
151-159
Jan. 11 - Jan. 15
9
9
3
profile No. IX
160-167
Jan. 22 - Jan. 24
7
9
3
profile No. X plus stations
168-181
Jan. 26 - Febr. 6
10
]4
8
in the open Arabian Sea
profile No. XI
182-190
Febr. 8-Febr.10
8
9
4
profile No. XII
193-202
Febr. 15 - Febr. 18
9
9
5
profile XIII
205 - 212
Febr. 20 - Febr. 26
8
7
4
profile No. XIV
213-221
Febr. 27 - Mar. 3
9
7
4
profile No. XV
222-230
Mar. 4 - Mar. 9
9
9
2
profile No. XVI
232-241
Mar. 11 - Mar. 13
8
11
NW profile into the
Gulf of Oman
242-249
Mar. 19- Mar. 24
8
15
Gulf of Oman
250-271
Mar. 24- Mar. 31
23
24
Gulf of Oman
379-368
Apr. 14-Apr. 16
Persian Gulf
272-378
Mar. 31- Apr. 14
65
41
30
231
227
99
west coast of India and Pakistan, where ostracods were dominant in the plankton, it was
necessary to add formalin to the plankton as soon as the catch carne on deck, as the
crustaceans severely damaged the delicate fish larvae by voracious feeding, even in the
bucket.
3. Variations in the Catch According to Net and Kind of Tow
The number of species caught per haul was generally lower in the HLN samples
than in the RT samples, and night catches were often more prolific than day catches.
In areas where a considerable number of HLN and RT day and night samples were
made, the mean difference between day and night is much more striking in the HLN
than in the RT tows. While the HLN samples showed a mean ratio for number of species
caught at night to number of species caught in daytime of 2.0, 2.5, and 3.8 in the three
areas, southern Red Sea to Gulf of Aden, Cape Guardafui to Mombasa, and the open