International Journal of Fisheries and Aquatic Studies
2019, Vol. 7, Issue 5, Part E
Gillnet selectivity of commercially important fish species in lake hashenge, Ethiopia
Author(s): Gashaw Tesfaye
Abstract: The present study was aimed to evaluate the selectivity of gillnets and the size at first maturity of commercially important fish species in Lake Hashenge mainly the Nile tilapia
Oreochromis niloticus and common carp
Cyprinus carpio. Experimental fishing was conducted using gillnets of different mesh sizes (60, 80, 100, 120 and 140 mm) in six sampling occasions from 2010 – 2011. A total of 2671 fish specimens consisting of 1184
O. niloticus and 1523
C. carpio were analyzed. Gillnet selectivity parameters for each mesh sizes were estimated for each species using the SELECT method. The size at first maturity (
Lm) and its 95% CI for
O. niloticus and
C. carpio were estimated at
23.9 cm (23.3 – 24.5 cm),
and 32.5 cm (31.6 – 33.4 cm), respectively. Results showed that a Log-normal model best described gillnets selectivity for
C. carpio, while a Normal location model best described for
O. niloticus. Capture probability estimates indicate that the optimum length of capture (
LCAP) of < 80 mm mesh size nets are smaller than the
Lm of both target species, while
LCAP of >120 mm mesh net selects above the
Lm value for both
O. niloticus and
C. carpio. Although the 100 mm mesh selects above the size of
Lm value for
O. niloticus, it still selects below the
Lm value for
C. carpio. Based on the results obtained, it was concluded that gillnets of mesh size 100 and 120 cm may safely be applied in Lake Hashenge fishery if proper level of effort is applied that ensures sustainability of both target species.
Pages: 403-409 | 1146 Views 482 DownloadsDownload Full Article: Click Here
How to cite this article:
Gashaw Tesfaye. Gillnet selectivity of commercially important fish species in lake hashenge, Ethiopia. Int J Fish Aquat Stud 2019;7(5):403-409.