Influence of Diadema antillarum populations (Echinodermata: Diadematidae) on algal community structure in Jardines de la Reina, Cuba

Abstract

The 1983-1984 mass mortality of Diadema antillarum produced severe damages on Caribbean reefs contributing to substantial changes in community structure that still persist. Despite the importance of Diadema grazing in structuring coral reefs, available information on current abundances and algal-urchin interactions in Cuba is scarce. We analyzed spatial variations in Diadema abundance and its influence on algal community structure in 22 reef sites in Jardines de la Reina, in June/2004 and April/2005. Urchins were counted in five 30x2m transects per site, and algal coverage was estimated in randomly located 0.25m side quadrats (15 per site). Abundances of Diadema were higher at reef crests (0.013-1.553 ind/m 2 ), while reef slope populations showed values up to three orders of magnitude lower and were overgrown by macroalgae (up to 87%, local values). Algal community structure at reef slopes were dominated by macroalgae, especially Dictyota, Lobophora and Halimeda while the most abundant macroalgae at reef crests were Halimeda and Amphiroa. Urchin densities were negatively and positively correlated with mean coverage of macroalgae and crustose coralline algae, respectively, when analyzing data pooled across all sites, but not with data from separate habitats (specially reef crest), suggesting, along with historical fish biomass, that shallow reef community structure is being shaped by the synergistic action of other factors (e.g. fish grazing) rather than the influence of Diadema alone. However, we observed clear signs of Diadema grazing at reef crests and decreased macroalgal cover according to 2001 data, what suggest that grazing intensity at this habitat increased at the same time that Diadema recruitment began to be noticeable. Furthermore, the excessive abundance of macroalgae at reef slopes and the scarcity of crustose coralline algae seems to be due by the almost complete absence of D. antillarum at mid depth reefs, where local densities of this urchin were predominantly low. Rev.

Small-Scale Variability Dominates Benthic Coverage and Diversity Across the Jardines de La Reina, Cuba Coral Reef System

“…The dominance of algae in JR was high and corroborates previous reports (Pina-Amargós et al, 2006;Martín-Blanco et al, 2011). High levels of algae are associated with degraded coral reefs (Aronson and Precht, 2006;Hughes et al, 2007).…”

“…The genera Dictyota and Halimeda were the two most abundant macroalgae in agreement with other studies in JR (Martín-Blanco et al, 2011), Cuba (Chiappone et al, 2001;Trelles et al, 2001;Blanco-Ojeda et al, 2016) and the Caribbean Szmant, 2002). JR harbors a high biomass of herbivorous fishes such as surgeon and parrot fishes (Pina-Amargós et al, 2014).…”

Higher population densities of the sea urchin Diadema antillarum linked to wave sheltered areas in north Puerto Rico Archipelago

“…There has been a slow and patchy recovery of D. antillarum populations throughout the Caribbean region (Miller et al , 2003; Weil et al , 2005; Steiner & Williams, 2006; Debrot & Nagelkerken, 2006; Brown-Saracino et al , 2007; Miller et al , 2007; Harborne et al , 2009; Seller et al , 2009; Idjadi et al , 2010; Martín-Blanco et al , 2010, 2011; Ruiz-Ramos et al , 2011; Soto-Santiago and Irizarry-Soto, 2013; Levitan et al . 2014).…”

“…Presently, D. antillarum is going through a slow and non-uniform recovery process in many Caribbean reefs where populations still exhibit low densities (Bak et al , 1984; Vicente & Goenaga, 1984; Hughes et al , 1985; Hunte et al , 1986; Miller et al , 2003; Lessios, 2005; Weil et al , 2005; Debrot & Nagelkerken, 2006; Noriega et al , 2006; Steiner & Williams. 2006; Sellers et al , 2009; Idjadi et al , 2010; Martín-Blanco et al , 2010, 2011; Ruiz-Ramos et al , 2011; Levitan et al ., 2014). Differences in recovery may be explained by physical factors such as wave exposure (Chollett et al , 2012).…”

Caracterización De La Población Del Erizo Marino De Espinas Largas Diadema Antillarum Philippi, 1845 (Echinodermata: Echinoidea) en El Oeste De Cayo Santa María, Villa Clara, Cuba

“…Cuando la densidad de individuos es cero, el porciento de macroalgas es variable y oscila entre el 0% hasta el 85% de cobertura (figura 3). Estos resultados se comportan de manera similar a los reportados para el Archipiélago Jardines de la Reina en 2004-2005; donde el porciento de cobertura de algas fue significativamente mayor en las pendientes de los arrecifes donde las densidades de la especie fueron cero o cercanas a cero (Martín-Blanco et al, 2011). En el segundo se encontró una correlación negativa significativa entre la densidad del erizo y la cobertura de macroalgas (Rodríguez-Barreras, 2015).…”