Chris Glass

The at-sea discarding of fish harvested from the ocean and its associated mortalities have been recognized and noted by fisheries scientists as inherent problems in the management of world fisheries for a great many years. Such practices constitute not only waste of a valuable resource but perhaps more importantly help contribute to observed decline in many of the world’s marine fisheries. This has led many to speculate that continuing bycatch and discard practices will lead to collapse of commercial fisheries and associated community infrastructure.

Studies designed to reduce bycatch are not new. However, due to increasing interest by Conservation/Environmental advocacy groups and subsequent political imperatives, there has been an explosion in development such of programs and techniques in recent years. While these studies have resulted in a small number of highly visible and notable successes, (for example the Nordmore grate and various turtle excluder devices), in general success has been limited. This may in-part reflect the ad hoc nature of many programs but lack of implementation of novel bycatch reduction devices may also reflect the conservative nature of fisheries managers. What is clear is that the most successful bycatch reduction devices are designed to exploit differences in reaction behaviors between different species of fish and or shellfish

This paper will explore some of the common approaches to bycatch reduction with particular emphasis on studies where species-specific behavior patterns have been identified and exploited. Examples from fisheries in the Scottish North Sea and the waters off the coast of New England will be used to illustrate how an understanding of fish behavior can be used to effectively reduce bycatch and discard in commercial fishing operations. The role of bycatch reduction in conservation of fish stocks will be discussed.