Benthic successional dynamics on settlement substrate in coral reefs lagoons

Several factors influence coral reef recovery, including availability of appropriate recruitment surface, which is provided mainly by crustose calcareous algae (CCA). Its role in coral recruitment has been amply documented, but the dynamics governing CCA availability has received little attention. This paper analyzes the benthic successional dynamics of six cover states [CCA, fleshy algae (FA), turf algae (TA), calcified articulated algae (CAA), free space, and other benthic groups] over a two-year period on patch reefs inside and outside Xcalak Reef National Park, a marine protected area (MPA) in the southern Mexican Caribbean. Recruitment tiles were used to mimic physical disturbance, and a Markov chain analysis was applied to understand the transition probabilities among benthic groups. Initial benthic succession was dominated by TA, which covered at least 75% of the surface. CCA were the dominant cover (similar to 50%), at stationary distributions, at sites inside the MPA, while at the site outside the MPA the dominant cover was TA (similar to 50%). Once CCA and TA occupied a space they had high probabilities of retaining it, with turnover rates similar to 1.5 years. These findings offer an entry point to the understanding at fine spatial scales of the dynamics of key benthic groups for coral recruitment and it constitutes the baseline to compare dynamics on reef adverse habitats.