Bycatch of Asteroidea from shrimp trawl fishery in the southwestern Atlantic Ocean - Brazil

Abstract

Shrimp trawling is considered a significant negative impact on the marine ecosystem, especially on the benthic community. Sea stars (Echinodermata: Asteroidea) are one of the most affected groups by unintentional catches. This study was performed at the Santana Archipelago, a Marine Protected Area in the northern region of Rio de Janeiro State, between 2008-2009. Sea stars accidentally caught by trawling were collected during open and closed season of the shrimp fisheries (Xiphopenaeus kroyeri) at depths of 5-60 m. A generalized linear zero-inflated model was applied to test for differences in capture between fishing seasons and depths. A total of 158 sea star specimens were captured. These specimens were identified as Asterina stellifera, Astropecten acutiradiatus, Astropecten brasiliensis, Astropecten cingulatus, Luidia alternata alternata, Luidia clathrata, Luidia ludwigi scotti, Luidia senegalensis. The sea stars A. brasiliensis and L. senegalensis are currently considered as vulnerable species in the Brazilian official list of threatened species. The higher capture of sea stars was shown in deepest areas, and there was no significant difference in the number of specimens between seasons. This is the first study about asteroids accidentally captured by shrimp trawling.

Keywords:
Benthos; Echinoderms; Fishing; Xiphopenaeus kroyeri