Abstract

The shelf-wide distribution of Antillean fish traps has been monitored in southwest Puerto Rico since 2002 to evaluate the benthic impacts of trap fishing within coralline habitats. Of 1438 traps documented in surface surveys to date, 161 traps were assessed by divers to quantify catch and trap-associated damage to sessile invertebrates; of these 39% were empty at the time of inspection. These data were used to assess trap catch (abundance, species composition) within habitats stratified by potential trap damage. Observed traps were predominantly arrowhead-style traps with 5-cm hexagonal vinyl-coated mesh composed either of wood (40%, n=65) or rebar frames (29%, n=46). Most traps inspected were found within colonized hardbottom habitats dominated by soft corals (63%, n=102) at intermediate depths (12-18 m). Fishes composed 78% of the total individuals caught (n=391), of which butterflyfishes, grunts, surgeonfishes, trunkfishes, and parrotfishes were most abundant. The banded butterflyfish, Chaetodon striatus (n=34), was the most frequently encountered fish species, whereas the foureye butterflyfish, Chaetodon capistratus (n=32), was the fish observed in the highest number of traps (n=17). Snappers and groupers composed only 7% of all observed fishes. The Caribbean spiny lobster, Panulirus argus, was the most numerous invertebrate (n=73, 85% of all invertebrates), the most numerous of any trapped organism (20% of the total), and was the most widely distributed (22% of all observed traps). The majority of trapped organisms (81%, n=316) was observed within colonized hardbottom and coral reef areas of moderate to high relief. Although sampled less frequently, contents observed in traps within less structured habitat types such as algal sand and mud consisted mostly of trunkfishes (19%, n=14) and grunts (15%, n=11). Within these habitats, P. argus was the most frequently observed species (32%, n=24), of which 58% were observed in algal sand habitat. Due to coincident presence of spiny lobster and a higher percentage of commercially valuable fish species within less complex habitats, the results suggest that fishers could prosper well by fishing traps only within areas of low structural complexity while lessening potential for gear damage of more complex habitat types.

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