A towed-diver survey method for mesoscale fishery-independent assessment of large-bodied reef fishes

摘要: Coral reef fishes are ecologically and economically important, particularly the largest species individuals, which often include top predators, as they show disproportionate fecundity generally make up basis of nearshore fisheries. Large-bodied coral can be difficult to sample using conventional survey methods, because relatively rare, have comparatively large home ranges, exhibit behaviors that influence their "sightability." We describe a towed-diver used assess populations these in pair SCUBA divers maneuver "towboard" dive planes record abundance size large-bodied (> 50 cm TL) while being towed at slow speed behind small boat for min. The resulting biological data georeferenced, allowing location-based comparison with habitat environmental data. Comparisons belt transect surveys within same habitats reveal similar archipelagic patterns, but some key differences. Encounter rates statistical power higher method, taxa behavioral responses different distribution patterns each method. scale allows more complete representative coverage shallow-water environment, improved large-scale estimates density spatial fishes. As result, method provides managers scientists an additional tool assessing status fish stocks.