McDermott and Lowe. Reproductive cycle and sexual maturity of Pleurogrammus monopterygius 
323 
Haul locations for Atka mackerel ovary samples; 541 = eastern Aleutians, 542 = central Aleutians, 543 = 
western Aleutians, 610 and 620 = Gulf of Alaska. 
Table 1 
Number of samples of Atka mackerel, Pleurogrammus monopterygius, collected from 1992 to 1994 by month and area. 
Month 
Eastern Aleutians 
Central Aleutians 
Western Aleutians 
Gulf of Alaska 
Total 
January 
85 
0 
0 
0 
85 
February 
55 
0 
0 
0 
55 
March 
68 
1 
9 
71 
149 
April 
0 
12 
71 
0 
83 
May 
0 
52 
45 
0 
97 
June 
62 
0 
72 
62 
196 
July 
0 
84 
83 
16 
183 
August 
0 
20 
10 
0 
30 
September 
0 
38 
0 
0 
38 
October 
0 
0 
0 
62 
62 
Total 
270 
207 
290 
211 
978 
and age at maturity and pooled by month only for 
the description of the reproductive cycle (Table 1). 
Atka mackerel were collected from subsamples of 
individual trawl tows. Collections were stratified by 
size of individual fish. No more than five fish per sex 
in each 1-cm size group were collected within each 
subarea during a sampling cruise. Each selected fish 
was measured to the nearest centimeter and weighed 
to the nearest 0.1 kg. In most cases, the stomach was 
emptied before weighing the individual fish. The 
ovaries were excised and placed in labeled cloth bags 
in a 10% buffered formalin solution. Sodium acetate 
(20 g per liter of formalin solution) was used as a 
buffer. Weights of fresh ovaries were taken and re- 
corded to the nearest gram for 254 specimens col- 
lected during the 1994 bottom trawl survey of the 
Aleutian Islands. In addition to the ovary samples, 
otoliths were collected opportunistically from 
sampled specimens. Ages were determined from 
otoliths by the Alaska Fisheries Science Center Age 
and Growth Unit using the surface-reading and break- 
and-burn technique (Chilton and Beamish, 1982). 
