Abundance, distribution and size structure of Diadema antillarum (Echinodermata: Diadematidae) in South Eastern Cuban coral reefs

Abstract

Abstract:The 1983-1984 mass mortality event of Diadema antillarum affected more than 93% of the total Caribbean population. Although there are no records about the status of Diadema populations before and after die-off on Cuban reefs, anecdotal information suggests that populations were struck. We analyzed spatial variation in the abundance and size structure of D. antillarum in 22 reefs sites in Jardines de la Reina, from June 2004 to September 2005. Counts of Diadema were performed in five 30x2m transects at each sampling site and sampling time, and test diameters were measured in September 2005 at the same fore reefs. Abundances were higher at reef crests (mean densities 0.08-2.18 ind./m 2 ), while reef slope populations reached a maximum site level of 0.13 ind./m 2 at only one site and showed values up to three orders of magnitude lower than those from reef crests. Highest abundance occurred at the west margin of major channels between keys where larval recruitment seems to be favored by local oceanographic features and facilitated by the abundance of Echinometra lucunter. The size frequency distribution of D. antillarum indicates that recruitment began to be noticeable three years before September 2005, suggesting these populations were depleted in the past and they are recovering now. Rev. Biol. Trop. 58 (2): 663-676. Epub 2010 June 02.

Effect of fish removal on the abundance and size structure of the sea urchinDiadema antillarum: A field experiment

“…In addition, higher densities of D. antillarum have been recorded in overfished areas where sea urchin predators have been significantly reduced (Edmunds & Carpenter 2001;Idjadi et al 2010). These and other studies (Brown-Saracino et al 2007;Harborne et al 2009;Martín-Blanco et al 2010) provide evidence in support of predation regulating the abundance of D. antillarum populations. Nonetheless, the effect of predators on the abundance and size structure of D. antillarum remains to be demonstrated experimentally (but see Kintzing & Butler 2014).…”

“…The highest current densities of D. antillarum have been reported in overfished areas such as Jamaica, and explained in terms of low abundance of predators (Sellers et al 2009;Clemente et al 2010;Idjadi et al 2010). Conversely, densities of D. antillarum have exhibited reductions in no-take reserves where fish stocks have recovered (Brown-Saracino et al 2007;Martín-Blanco et al 2010;Mercado-Molina et al 2015). Nevertheless, small labrids (wrasses) are usually excluded and dismissed as potential predators of D. antillarum (see Harborne et al 2009).…”

The Great Diadema antillarum Die-Off: 30 Years Later

“…Density values also fluctuated widely between censuses in St. John and Jamaica. The most likely explanation (beyond measurement error) is that there were Chiappone et al 2013;Lessios 1995Lessios , 2005Martin-Blanco et al 2010;Miller et al 2003;Williams & Polunin 2001). Direct observations of D. antillarum larval settlement suggest that recruitment in postmortality populations has been persistently limited for decades, but that the larval supply may be slowly increasing.…”

Revisiting the population status of the sea urchinDiadema antillarumin northern Puerto Rico

“…Conversely, the number of adults and juveniles were higher at BTAM which is a site with a consolidated substratum, low topographic relief, small boulders and relative few crevices. Martín-Blanco et al (2010) and Rodríguez-Barreras et al (2014) also found little evidence to assert that more topographically complex reefs sustain greater numbers of sea urchins (juveniles or adults). Karlson & Levitan (1990) argue that populations of D. antillarum are recruitment-limited.…”