Sex ratio, gonad maturity and size-structure of Pagelus bellotti in Sierra Leone

A total of 135 specimens of Pagellus bellotti were randomly collected from artisanal boats in August 2018. Study of sex ratio, gonad maturity and size-structure of Pagellus bellottii is meagre in Sierra Leone, and forms the basis of the present study. The study will contribute to current knowledge...

Full description

Bibliographic Details
Main Authors: A. Mansaray, K.J. Konomiya
Format: Article
Language:English
Published: Joint Coordination Centre of the World Bank assisted National Agricultural Research Programme (NARP) 2021-02-01
Series:Journal of Applied Sciences and Environmental Management
Subjects:
Online Access:https://www.ajol.info/index.php/jasem/article/view/203997
_version_ 1797228136710012928
author A. Mansaray
K.J. Konomiya
author_facet A. Mansaray
K.J. Konomiya
author_sort A. Mansaray
collection DOAJ
description A total of 135 specimens of Pagellus bellotti were randomly collected from artisanal boats in August 2018. Study of sex ratio, gonad maturity and size-structure of Pagellus bellottii is meagre in Sierra Leone, and forms the basis of the present study. The study will contribute to current knowledge and promote rational exploitation of the stock. Length and weight were measured using a fish measuring board (cm) and digital weight scale (g) respectively. Sex and gonad maturity were macroscopically assessed. Results showed dominant males (71.9%) and significant difference observed (1:2.6) and expected (1:1) female: male sex ratios (p <0.05). Only 11.9% and 11.1% of male and female gonads transcended to the developed stage (Stage IV). The length-frequency distribution for combined sex was unimodal (modal class, 17cm-20.9cm). Mean length and weight respectively were, 19.04±0.32cm and 98.85±5.08g for males and 17.43±0.54cm and 78.61±6.32g for females. Growth exponent (b) for male, female and combined sex was 2.809, 2.928 and 2.850 respectively and the correlation coefficient for all sex categories showed (r > 0.9). Indexes of condition were greater than 1.0 (K > 1) for all sex categories. Results portrayed a heterogeneous gender population of Pagelus bellottii and vast similarity in reproductive strategies by both sexes. The fish comprised of one size group and males may be growing larger than the females. Growth pattern was near-isometric for females and negative allometric for the males, and both sexes were in better condition (K >1.0). An annual study could provide further insight.
first_indexed 2024-04-24T14:51:54Z
format Article
id doaj.art-e946aa2cbf4b417a86b5c693fd1fe656
institution Directory Open Access Journal
issn 2659-1502
2659-1499
language English
last_indexed 2024-04-24T14:51:54Z
publishDate 2021-02-01
publisher Joint Coordination Centre of the World Bank assisted National Agricultural Research Programme (NARP)
record_format Article
series Journal of Applied Sciences and Environmental Management
spelling doaj.art-e946aa2cbf4b417a86b5c693fd1fe6562024-04-02T19:48:35ZengJoint Coordination Centre of the World Bank assisted National Agricultural Research Programme (NARP)Journal of Applied Sciences and Environmental Management2659-15022659-14992021-02-01241210.4314/jasem.v24i12.22Sex ratio, gonad maturity and size-structure of Pagelus bellotti in Sierra LeoneA. MansarayK.J. Konomiya A total of 135 specimens of Pagellus bellotti were randomly collected from artisanal boats in August 2018. Study of sex ratio, gonad maturity and size-structure of Pagellus bellottii is meagre in Sierra Leone, and forms the basis of the present study. The study will contribute to current knowledge and promote rational exploitation of the stock. Length and weight were measured using a fish measuring board (cm) and digital weight scale (g) respectively. Sex and gonad maturity were macroscopically assessed. Results showed dominant males (71.9%) and significant difference observed (1:2.6) and expected (1:1) female: male sex ratios (p <0.05). Only 11.9% and 11.1% of male and female gonads transcended to the developed stage (Stage IV). The length-frequency distribution for combined sex was unimodal (modal class, 17cm-20.9cm). Mean length and weight respectively were, 19.04±0.32cm and 98.85±5.08g for males and 17.43±0.54cm and 78.61±6.32g for females. Growth exponent (b) for male, female and combined sex was 2.809, 2.928 and 2.850 respectively and the correlation coefficient for all sex categories showed (r > 0.9). Indexes of condition were greater than 1.0 (K > 1) for all sex categories. Results portrayed a heterogeneous gender population of Pagelus bellottii and vast similarity in reproductive strategies by both sexes. The fish comprised of one size group and males may be growing larger than the females. Growth pattern was near-isometric for females and negative allometric for the males, and both sexes were in better condition (K >1.0). An annual study could provide further insight. https://www.ajol.info/index.php/jasem/article/view/203997Allometric growthcohortcondition factorgonad maturityisometric growth
spellingShingle A. Mansaray
K.J. Konomiya
Sex ratio, gonad maturity and size-structure of Pagelus bellotti in Sierra Leone
Journal of Applied Sciences and Environmental Management
Allometric growth
cohort
condition factor
gonad maturity
isometric growth
title Sex ratio, gonad maturity and size-structure of Pagelus bellotti in Sierra Leone
title_full Sex ratio, gonad maturity and size-structure of Pagelus bellotti in Sierra Leone
title_fullStr Sex ratio, gonad maturity and size-structure of Pagelus bellotti in Sierra Leone
title_full_unstemmed Sex ratio, gonad maturity and size-structure of Pagelus bellotti in Sierra Leone
title_short Sex ratio, gonad maturity and size-structure of Pagelus bellotti in Sierra Leone
title_sort sex ratio gonad maturity and size structure of pagelus bellotti in sierra leone
topic Allometric growth
cohort
condition factor
gonad maturity
isometric growth
url https://www.ajol.info/index.php/jasem/article/view/203997
work_keys_str_mv AT amansaray sexratiogonadmaturityandsizestructureofpagelusbellottiinsierraleone
AT kjkonomiya sexratiogonadmaturityandsizestructureofpagelusbellottiinsierraleone