Changes in Coral Reef Communities and an Associated Reef Fish Species, Cephalopholis cruentata (Lacépède), After 30 years on Curaçao (Netherlands Antilles)

Abstract

Using the same methodology and identical sites, we repeat a study dating from 1973 and quantify cover of hard coral species, soft corals, sponges, hard substratum and soft substratum, and density of a commercially important reef fish species, the graysby Cephalopholis cruentata, along a depth-gradient of 3-36 m on the coral reefs of Curac¸ao. The objective was to determine the multi-decade change in benthic coral reef cover and structural complexity, and their effect on densities of an associated reef fish species. Total hard coral cover decreased on average from 52% in 1973 to 22% in 2003, representing a relative decline of 58%. During this time span, the cover of hard substratum increased considerably (from 11 to 58%), as did that of soft corals (from 0.1 to 2.2%), whereas the cover of sponges showed no significant change. Relative decline of hard coral cover and of reef complexity was greatest in shallow waters (near the coast), which is indicative of a combination of anthropogenic influences from shore and recent storm damage. Cover of main reef builder coral species (Agaricia spp., Siderastrea siderea, Montastrea annularis) decreased more than that of other species, and resulted in a significant decrease in reef complexity. Although density of C. cruentata was highly correlated to cover of Montastrea and Agaricia in 1973, the loss of coral cover did not show any effect on the total density of C. cruentata in 2003. However, C. cruentata showed a clear shift in density distribution from shallow water in 1973 to deep water in 2003. It can be concluded that the reefs of Curac¸ao have degraded considerably in the last three decades, but that this has had no major effect on the population size of one commercially important coral-associated fish species.

Coral Community Decline at Bonaire, Southern Caribbean

“…Status of Bonaire's Coral Reef Benthic Communities.-Findings of the present study are consistent with results from other recent benthic studies from the Netherlands Antilles (Bak and Luckhurst 1980, Bak and Nieuwland 1995, Bak et al 2005, Nagelkerken et al 2005. The combination of low to moderate coral cover and algal dominance at the vast majority of sites raises concerns about the status of Bonaire's coral reefs.…”

Loss of Structural Complexity in Staghorn Coral Rubble Habitats Influences the Density of Damselfish in Dry Tortugas National Park, Florida, USA

“…Although several factors in addition to structural complexity have been previously linked to reef fish density, including the nearby presence of live coral, benthic macroalgae, depth, fish community, and relative fishing pressure (Bell and Grazin, 1984;Chabanet et al, 1997;Ö hman and Rajasuriya, 1998;Jones et al, 2004;Nagelkerken et al, 2005;Medeiros et al 2010;Precht et al 2010), these factors are similar between our study sites (J. Grim et al, unpubl.).…”

40 Years of benthic community change on the Caribbean reefs of Curaçao and Bonaire: the rise of slimy cyanobacterial mats

“…The few existing temporal studies that have included reefs below 20 m show that reef degradation also occurs on upper mesophotic reefs (down to 40 m) (e.g. Bak et al 2005;Nagelkerken et al 2005;Nugues and Bak 2008;De Bakker et al 2016a).…”

“…Diaz and Rützler 2001;De Goeij et al 2013). Sponge cover appears to have remained relatively steady for a long time period (Nagelkerken et al 2005). However, new studies describe a recent increase in sponge densities (e.g.…”

“…Deeper reefs ([20 m) have rarely been considered in longterm ecological studies (but see Bak and Luckhurst 1980;Bak et al 2005;Nagelkerken et al 2005;Nugues and Bak 2008;De Bakker et al 2016a). Our study shows that the observed main trends in community dynamic occurred down to 40 m depth.…”