Are Abrolhos no-take area sites of naïve fish? An evaluation using flight initiation distance of labrids

Abstract

Fishing pressure affects the behavior of reef fish, especially of fishery-targeted species. In this context, it is critical to understand if fish behavior is preserved in no-take areas (NTAs), which are considered the best instrument for the recovery of fish stocks. Comparing the flight initiation distances (FIDs) of fish inhabiting multiple-use areas (MUAs), where fishing is allowed (including spearfishing), and NTAs is a useful approach to test whether NTAs can be effective as fish refuges. Here, we compared whether the FIDs of two target (Sparisoma axillare and Scarus trispinosus) and one non-target (Halichoeres poeyi) labrids are greater in the MUAs than in the NTAs. We also investigated whether group size (GS) and body size (BS) exert any effect on the FID. We sampled four MUAs and four NTAs in the Abrolhos Bank (Brazil). We found that only for the targeted species FID was shorter inside the NTAs and that the BS had a positive effect on the FID of all species. The GS and BS of the fish are greater in the NTAs than in the multiple-use areas only for S. trispinosus. Our study shows that fish, especially those species that are fishery targets, display an avoidance behavior against spearfishermen likely as a consequence of fishing pressure. We suggest that the NTAs in Abrolhos are not only important sites for the recovery of fish stocks but also possibly act as a repository area of naïve fish (fish that allow human approach), for reefs open for fishing.A pressão pesqueira afeta o comportamento de peixes recifais, especialmente nas espécies alvo de pesca. Nesse contexto é importante entender se áreas fechadas a pesca ("no-take areas": NTAs), consideradas como melhor instrumento para recuperação dos estoques pesqueiros, garantem a integridade dos comportamentos dos peixes. Comparar distâncias iniciais de fuga ("fligth initiation distance": FIDs) de espécies entre recifes de uso múltiplos ("multiple-use areas": MUAs), onde a pesca é permitida (incluindo a pesca submarina), e as NTAs é uma abordagem útil para testar se as NTAs podem ser efetivas como refúgios para peixes recifais. Nesse trabalho FIDs de duas espécies alvo (Sparisoma axillare e Scarus trispinosus) e uma não alvo (Halichoeres poeyi) foram comparadas entre MUAs e NTAs. A possível influência do tamanho do grupo ("group size": GS) e o tamanho do corpo ("body size": BS) sobre FID também foram investigados. Foram amostradas quatro MUAs e quatro áreas NTAs no banco dos Abrolhos (Brasil). Nossos resultados mostraram que apenas FID das espécies alvo de pesca foi menor dentro de NTAs e que o BS teve um efeito positivo no FID de todas as espécies. Dentro da NTA, GS e BS foram maiores do que em recifes abertos à pesca apenas para S. trispinosus. Finalmente, sugerimos que NTAs em Abrolhos não são apenas importantes como recuperação dos estoques pesqueiros, mas estão possivelmente atuando como uma área repositória de peixes "ingênuos" (peixes que permitem aproximação humana) para os recifes onde a pesca é permitida.

First fish fauna assessment in the Fernando de Noronha Archipelago with BRUVS: Species catalog with underwater imagery

“…In regard to traditional underwater visual census, a widespread technique to study reef fishes, fish-scuba diver interactions are a common methodological bias (Kulbicki, 1998;Harvey et al, 2002). This is specifically problematic when studying large bodied species, such as groupers, snappers and parrotfishes (Gotanda et al, 2009;Januchowski-Hartley et al, 2011), commonly targeted along the tropical coast of Brazil (Nunes et al, 2012(Nunes et al, , 2016.…”

Range extension of Guyanella clenchi (Altena, 1968) (Bivalvia, Lucinidae) with new records from Abrolhos Bank, Brazil

“…The new geographic data available for G. clenchi suggests that this species may have a continuous distribution from the Caribbean to northeastern Brazil. This geographical pattern can be found in many other mollusc species (Mikkelsen and Bieler 2007, Rios 2009 and other marine invertebrates (Barreira and Margarida 1994), despite high endemism of coral species (Leão 1999, Segal and Castro 2000, Leão and Kikuchi 2001, Nunes et al 2016, Zilberberg et al 2016 and reef fish (Moura 2000, Dutra et al 2005, Nunes et al 2016 occurs at Abrolhos Bank. Moreover, Absalão (2005) suggested that the region may constitute a discreet biogeographical unity, with as much as 12.9% of the mollusc species being endemic, although not other groups, like Crustacea and Polychaeta (Dutra et al 2005).…”

“…The Abrolhos Bank (17°20′-18°00′S and 038°30′-039°30′W) (Fig. 2B) is a 200 km thickening of the Eastern Brazilian Continental Shelf that harbours the largest and richest coral reef complex of the Southern Atlantic (Leão 1999, Leão et al 2003Nunes et al 2016). The local reef structures differ from their Caribbean counterparts by their morphology, sediment types, and organisms involved in their construction (Leão 1999, Leão et al 2003, Zilberberg et al 2016.…”