Assessment of Exploited Population Dynamics of African Butter Catfish (Schilbe mystus) in Stratum VII of Lake Volta, Ghana
Date
2023
Journal Title
Journal ISSN
Volume Title
Publisher
Egyptian Journal of Aquatic Biology & Fisheries
Abstract
The current study aimed to assess the population status of Schilbe
mystus in stratum VII of Volta Lake, Ghana, based on length-frequency
data collected throughout 2021. Individual fish samples, ranging from 5.5 to
22.0cm with a mean length of 11.5± 0.17cm, were analyzed using FiSAT II.
The study revealed a mean condition factor of 0.36, indicating the fish's
overall health. The growth pattern, estimated at 3.1 suggested positive
algometric growth. The growth rate (K) was determined as 0.25 per year.
Length at infinity (L∞), length at first capture (Lc50), and length at first
maturity (Lm50) were calculated as 24.7, 10.27, and 16.47cm, respectively.
The growth performance index was recorded at 2.58. The total mortality rate
(Z) was calculated as 2.09 per year, with the natural mortality rate (M) at
0.78 per year and the fishing mortality rate (F) at 1.31 per year. The
exploitation rate was 0.63, indicating overexploitation of S. mystus in
Stratum VII. To sustain the stock size of the S. mystus fishery in Lake Volta,
we recommend reducing fishing efforts, regular status assessments, and
enforcement of fisheries regulations
Description
Research Article
Keywords
Exploitation rate, FiSAT II, Fisheries management, Growth rate