Design strategies of cast nets in Escravos Estuary within Okerenkoko axis of Delta State, Nigeria

Abstract

Fishing gear design is the process of preparing technical specifications that will aid in providing sections of the gear drawing. This painstaking examination is to ensure proper gear handling technique and operation, including satisfying economic and social considerations. The design strategies of cast net in Escravos Estuary within Okerenkoko, Delta State, Nigeria was studied in three stations: Station 1 {University Jetty (UJ)}, Station 2 {Zion Jetty (ZJ)} and Station 3 {Vigilante Jetty (VJ)} between April and June, 2025. Two types of castnets were identified in the study area. The cast nets had length circumference ranging from 4.0 to 8.0 m, the retrieval lines measuring between 3.0 to 6.0 m while the thickness ranged from 3.0 to 6.0 mm. The netting material used in the study area consisted of R 100 – 310 tex polyamide twines of z – twist disposition with stretched mesh sizes ranging from 25 to 50 mm with hanging ratio of 0.5. It was observed that the netting section of the cast nets were horizontally segmented into panels.The segmented cast nets consisted of two to three segments and each segment was found to be made of netting with different mesh sizes (50 mm, 30 mm and 25 mm) and R – tex twine sizes. This range of mesh sizes observed in most of the cast nets in the study area were in line with the Inland Fisheries Decree 108 of 1992, especially cast nets used in fishing species such as Ethmalosa fimbriata and Sardine llaaurita in the study area. The results revealed that, polyamide nettings were the most commonly used materials in constructing the cast nets, and this polyamide netting materials are highly recommended for use in constructing cast nets due to their high quality and tensile strength. This is a pilot study in the area for cast nets fisheries, but more studies are still needed to provide tangible recommendations.