Salmonid Field Protocols Handbook: Techniques for Assessing Status and Trends in Salmon and Trout

Beach Seining

Peter K. J. Hahn, Richard E. Bailey, and Annalissa Ritchie

doi: https://doi.org/10.47886/9781888569926.ch14

Seining is a fishing technique traditionally done in areas with large schools or groups of fish. The earliest form of seining was dragnetting (also called beach seining). There is evidence of seine nets used in artisanal fisheries several thousands of years ago and on every continent (von Brandt 1984), including North America, where native peoples used them to catch salmon in the Columbia River (Craig and Hacker 1940) (see Appendix B) and elsewhere. Nets ranged in size from very small, single-person “stick seines” to seines in New Zealand that measured more than 1,600 m long and employed hundreds of people to retrieve.

The typical modern seine net has weights on the bottom (lead line) and buoys on the top (float or cork line) to keep the net vertical when pulled through the water to entrap fish. Some seine nets are designed to sink or to float, but most remain in constant contact with both the bottom and the surface and thus are best suited for shallow waters. A beach seine is often set from shore to encircle a school of fish and is then closed off to trap them against the shore. One variation is to set a seine net parallel to and some distance from shore and then pull it to the beach. Another variation is to encircle fish some distance from shore but still in shallow water and pull the net onto boats. This latter method evolved into the purse seine, which has rings along the lead line through which a rope is pulled to “purse” or tighten the bottom of the net together before the net is gathered to the side of a boat; purse seines, however, are not limited to shallow waters for their effectiveness. Between a beach and purse seine is the lampara net, which is fished at the surface in deep water. It has a lead line much shorter than the float line, which shapes the seine much like a dust pan and prevents epipelagic fish from diving and escaping (von Brandt 1984; Hayes et al 1996). Some seines are even fished through holes cut in ice-covered lakes to capture semitorpid aggregations of fish.