Drivers of distribution of the parrotfish Sparisoma frondosum (agassiz, 1831) in Southwest Atlantic rocky reefs: Insights for management and conservation

Abstract

Abstract Understanding the effects of environmental drivers on fish distribution is of primary importance for designing effective conservation measures to protect endangered species. In this study, we investigated which habitat and spatial predictors enhance the abundance and biomass of the parrotfish Sparisoma frondosum in tropical rocky reefs from a Southwest Atlantic insular complex. Besides more than 170 islands, the Ilha Grande Bay (IGB) also harbors one of the most threatened Brazilian Marine Protected Area (MPA), the Ecological Station of Tamoios (ESEC–Tamoios). This no-take MPA became an emblematic area of the systematic dismantling of Brazilian environmental laws ongoing since the beginning of 2019 when the current government has declared intentions to recategorize and reduce the ESEC-Tamoios protection status. Our results revealed that distance from the coast and depth better explained the distribution of the iconic and vulnerable S. frondosum, regardless the presence of the no-take areas. An overall trend of increasing abundance and biomass with distance and depth was observed, except for sites with high cover of invasive coral Tubastraea spp. We also discuss the ESEC-Tamoios effectiveness and its current panorama to the Southwest Atlantic rocky reef s conservation. Finally, we identify strategies to protect parrotfishes and expand the ecological benefit of this MPA to adjacent areas.