codends

A codend is the rear section of a fishing net, such as a trawl or gillnet, in which the catch is collected and retained as the rest of the net passes through the water. In a trawl, the codend is typically a separate bag or cone at the end of the net, connected to the bunt and body, and it usually has a finer mesh than the preceding sections to limit escape.

Construction and materials commonly involve synthetic fibers such as nylon (polyamide) or polyethylene. Codends can be shaped as straight or tapered sections and use different mesh patterns, including diamond or square mesh. The design may include reinforcements or liners to withstand wear during towing and hauling.

Variants and selectivity considerations are an important aspect of codend design. Some codends incorporate square-mesh panels or escape openings intended to allow undersized fish or certain unwanted species to escape, thereby improving selectivity and reducing discards. There are also specialized selective codends and configurations—sometimes used in conjunction with bycatch reduction devices—to influence which animals are retained.

Regulatory and practical context: The design and mesh size of codends can influence catch composition and bycatch rates, making codend specifications a focus of fisheries management in many regions. Regulations may set minimum or specific mesh sizes and guidelines to promote sustainability and reduce waste.

Maintenance and replacement: Codends endure substantial wear from towing and handling, so they are routinely inspected for holes and tears and replaced or repaired as needed to maintain performance and safety.