Spatial distribution and diet of Cephalopholis fulva (Ephinephelidae) at Trindade Island, Brazil

Abstract

In this study we analyze the population structure and diet of the coney Cephalopholis fulva at Trindade Island, Brazil, through direct observation with SCUBA diving in 11 reef sites around the Island, up to 50 m deep. Diet was based on 77 individuals collected with speargun. Mean population density and biomass were estimated at 29 individuals/100 m 2 and 13 kg/100 m 2 , respectively. This species is regularly distributed along the costal environments of the Trindade Island, with no significant differences in densities and biomass detected among the different collection habitats (reef crest, reef slope, and reef plateau). However, significantly higher densities were observed micro-habitats with greater structural complexity, which may offer more shelter and food to C. fulva. Four food item groups were identified from the gut contents of C. fulva: Annelida, Crustacea, Teleostei, and Testudinata. It is the first record of predation of the green turtle Chelonia mydas hatchlings by the coney. Trindade Island seems to present the densest concentration of C. fulva in all Brazilian and Caribbean ecosystems inhabited by this species. Scarcity of competitors, predators, and fishing pressure may explain the high densities observed in the Island.Foram analisadas a estrutura populacional e a dieta do catuá Cephalopholis fulva na Ilha da Trindade, Brasil. Os dados foram obtidos através de censos visuais com mergulho autônomo em 11 locais no entorno da ilha, em profundidades de até 50 m. A dieta e a proporção sexual foram baseadas na análise de 77 indivíduos coletados com arpão. A densidade populacional e biomassa foram estimados em 29 indivíduos/m² e 13 kg/100 m², respectivamente. A espécie apresentou distribuição uniforme nos ambientes costeiros da ilha, não tendo sido registradas diferenças significativa em sua densidade e biomassa entre os diferentes habitats estudados (crista, talude e platô recifal). Entretanto, foi observado preferência por micro-habitats de alta complexidade estrutural. Foram registrados quatro grupos de itens alimentares no conteúdo estomacal de C. fulva: Annelida, Crustacea, Teleostei e Testudinata. É feito aqui o primeiro registro de predação de juvenis da tartaruga-verde (Chelonia mydas) por C. fulva. Trindade parece apresentar os maiores valores de densidade para o catuá, quando comparada a outras localidades do Brasil e Caribe. A escassez de competidores, predadores e a pressão pesqueira são possíveis fatores que podem explicar as altas densidades observadas para C. fulva na Ilha da Trindade.

Habitat use of five sympatric predatory reef fishes at a remote island in the south‐western Atlantic

“…Such homogenous distributional patterns explain why no significant differences among sites were found when C. fulva's populational descriptors were analysed versus the factor 'sites'. Our findings corroborate the results reported by Coelho et al (2012) (Guabiroba, Santos, et al, 2020b). The R. saponaceus population also showed a homogeneous distributional pattern, being detected in all six sampled sites.…”

“…According to Coelho et al . (2012), no significant differences were detected for C. fulva density, either horizontally (across sites) or vertically (across different depth strata) (see Coelho et al ., 2012). According to Guabiroba, Santos, et al .…”

“…According to Coelho et al . (2012), C. fulva 's population on TRI is the densest compared to the Caribbean and coastal Brazilian populations. Despite the unusual high density of C. fulva 's populations on TRI, constant anthropic pressure has reduced the populations over time (Guabiroba, Santos, et al ., 2020b).…”

“…Our findings corroborate the results reported by Coelho et al . (2012) regarding the spatial distribution of C. fulva across 11 sites around TRI. According to Coelho et al .…”

Presence of the Seahorse Hippocampus reidi (Pisces: Syngnathidae) In Diet of Marine Fish in Northeastern Brazil

“…Its diet is composed of small fish and crustaceans and is a daytime predator that exhibits a sit-and-wait strategy, staying close to the bottom [17][18][19]. Predation of juveniles of the green turtle (Chelonia mydas) by the coney has been observed, along with annelids, which were found in their stomach contents [20]. According to Oliveira et al [21], the coney is fished in the range of 100 to 200 m deep, which is in agreement with the range where the fish that contained the seahorse in its mouth was fished.…”