当前位置： SCI文献检索 > JOURNAL OF FISH BIOLOGY期刊下所有文献 > Reproductive biology and implications for management of the spangled emperor Lethrinus nebulosus in the southern Arabian Gulf.

Reproductive biology and implications for management of the spangled emperor Lethrinus nebulosus in the southern Arabian Gulf.

Abstract：

:The reproductive biology of the spangled emperor Lethrinus nebulosus in the southern Arabian Gulf was determined from the examination of 781 individuals collected between September 2008 and August 2009. There was no histological evidence of adult sex change, and sex ratios did not differ significantly from unity across all size and age classes. Testes had an ovarian structure and a remnant lumen which was not used for sperm transport; furthermore, residual oocytes were observed in the testes of some immature, resting and developing males. A dramatic change in the sex ratio of the smallest and youngest size and age classes suggested that juvenile female to male sex change occurred between 21·0 cm fork length (L(F)) and 24·0 cm L(F) at 1 year of age. The combination of histological evidence with the sexual composition of the size and age structures suggests a non-functional protogynous hermaphroditic sexual pattern, which is analogous to functional gonochorism. The spawning season was well defined, occurring once a year during March, April and early May. Peaks in spawning occurred after full moons, there was a cessation in spawning activity after new moons and spawning was completed within three lunar cycles. The distribution of males over the entire size and age ranges and the absence of inactive mature females during the spawning season suggested that the population was not constrained by sperm limitation. Size-specific and age-specific reproductive potential indicated that conventional regulations that equate the mean size at first capture to sexual maturation are unsuitable for the management of L. nebulosus. The maximum recorded age (11 years), small mean size and young age at sexual maturation (L(m50) = 26·7 cm L(F), 2·1 years, for females and 19·4 cm L(F), 0·5 years, for males) may be a direct result of intensive demersal fishing in the southern Arabian Gulf.

journal_name

J Fish Biol

journal_title

Journal of fish biology

authors

Grandcourt EM,Al Abdessalaam TZ,Francis F,Al Shamsi AT

doi

10.1111/j.1095-8649.2010.02799.x

subject

Has Abstract

pub_date

2010-12-01 00:00:00

pages

2229-47

issue

eissn

0022-1112

issn

1095-8649

journal_volume

pub_type

杂志文章

在线工具

Reproductive biology and implications for management of the spangled emperor Lethrinus nebulosus in the southern Arabian Gulf.