A review and synthesis of the benefits, drawbacks, and considerations of using traps to survey fish and decapods

Abstract

Traps (or pots) are one of the oldest and most widespread scientific survey gears for fish and decapod crustaceans around the world. Here, I review and synthesize the extensive scientific literature describing the various benefits and drawbacks of using traps as a survey gear in scientific studies. The widespread use of traps in fish and decapod surveys is due to several characteristics like their low cost, flexible design, ease of use, ability to fish unattended, and being amenable to pairing with other gears. However, there are a number of significant drawbacks of using traps, including highly variable catches due to environmental fluctuations or behavioral interactions or lost traps that continue catching and killing animals, that must be considered and accounted for when initiating trap surveys. This study highlights the types of habitats and species most and least suited for monitoring by traps, and emphasizes the importance of matching the goals and objectives of a trap survey with the correct trap design, mouth entrance, bait type, soak time, and pairing of gears. Pilot studies are also recommended before surveys are initiated to quantify the selectivity patterns of traps and identify the various factors that may influence trap catch.