Fecundity of the snapperChrysophrys auratus(Pisces: Sparidae) from the Hauraki Gulf
作者:
James Crossland,
期刊:
New Zealand Journal of Marine and Freshwater Research
(Taylor Available online 1977)
卷期:
Volume 11,
issue 4
页码: 767-775
ISSN:0028-8330
年代: 1977
DOI:10.1080/00288330.1977.9515712
出版商: Taylor & Francis Group
数据来源: Taylor
摘要:
Fecundity estimates were made for snapperChrysophrys auratus, a serial spawning fish, for the 1974–75 and 1975–76 spawning seasons. Weighed sub‐samples of ovaries were used, and eggs were counted manually. All eggs >0.1 mm diameter were considered potentially capable of being spawned; estimates of these eggs were made at the beginning and end of spawning, and their difference was considered to be the actual fecundity. A log‐log transformation of egg numbers against length offish gave a linear relationship. Fecundity estimates ranged from 297 000 at 25 cm to 4 528 000 at 50 cm in 1974–75, and from 83 000 at 25 cm to 6 164 000 at 50 cm in 1975–76. Counts of ripe eggs were also made, and batch sizes ranging from 13 000 at 25 cm to 104 000 at 50 cm were predicted. By combining these data with fecundity estimates the number of batches spawned was estimated to be 23–44 in 1974–75, depending on and increasing with length; and 6–59 in 1975–76.
点击下载:
PDF (636KB)
返 回