Recruitment dynamics and microhabitat selectivity of coral-reef fishes at three sites in the Mexican Caribbean

• Published in: Environmental biology of fishes Vol. 105; no. 6; pp. 753 - 773
• Main Authors: H, Villegas-Hernández, C, González-Salas, S, Guillén-Hernández, G, Poot-López
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.06.2022; Springer Nature B.V
• Subjects: Abundance; Animal Systematics/Taxonomy/Biogeography; Benthos; Biological settlement; Biomedical and Life Sciences; Community composition; Density; Dominant species; Ecological distribution; Environment; Fish; Freshwater & Marine Ecology; Fronts; Geographical distribution; Habitats; Herbivores; Ichthyofauna; Lagoons; Life Sciences; Marine fishes; Marine invertebrates; Microenvironments; Microhabitat; Microhabitats; Nature Conservation; Recruitment; Recruitment (fisheries); Redundancy; Reef fish; Reef fishes; Reefs; Sampling; Scales; Selectivity; Similarity; Spatial analysis; Species composition; Substrates; Temporal variations; Thalassoma bifasciatum; Zoology; Microhabitat; Mahahual; Spatio-temporal variation; Recruits; Reef fishes
• ISSN: 0378-1909; 1573-5133
• DOI: 10.1007/s10641-022-01291-z

The settlement and post-recruitment processes are key to understanding certain ecological phenomena that occur in the life of a fish. Hence, the objective of this work was to analyze the spatio-temporal variation of reef fish in the recruitment stage of three reef sites (known as Bermejo, Quebrado, and Cabañas) in Mahahual (Mexico) through visual censuses. A hierarchical sampling was carried out considering six transects for two microhabitats (reef lagoon and reef front) for each site per month of sampling, from October 2017 to June 2018. In each sampling, the coverage of the marine substrate was analyzed through video transects. First, a spatial analysis was performed with a two-way nested similarity analysis (ANOSIM) and a similarity percentage analysis (SIMPER) with the monthly abundances. Then, a canonical redundancy analysis (RDA) was performed to evaluate the relationship between recruitment and coverage of benthic substrates. The recruited ichthyofauna recorded consisted of 15,732 recruits from 46 reef fish species. The most abundant species were Thalassoma bifasciatum , Abudefduf saxatilis , and Halichoeres bivittatu s. The site with the highest density was Cabañas, with average values of 29.39 recruits 100 m −2 in the reef lagoon and 20.37 recruits 100 m −2 in the reef front. In contrast, the lowest average densities were recorded in Bermejo, with 16.49 and 13.26 recruits 100 m −2 in the lagoon and the reef fronts, respectively. Temporarily, the highest values of recruit density were observed from June to September in the three sites, while February registered the lowest density. Four species were identified with higher abundances for reef lagoon, while ten species were preferentially recruited at the reef front. The ANOSIM results indicated significant differences in the species composition of recruits only at the microhabitat level and not at the site level. The temporal approach also showed significant effects between microhabitats on most of the months, suggesting that the true differences are at a spatial scale of the microhabitat (lagoon and reef front). SIMPER showed that the average dissimilarity between microhabitats is close to 70%, in which T. bifasciatum , H. bivittatus , and A. saxatilis were the species that contribute the most (55–70%) to the differences between lagoon and reef front. The highest dissimilarities were observed between the summer months (July to September) and the end of the northerly wind season (February to March). RDA showed that the average coverage of benthic substrates influenced the distribution of the abundance of the recruit species, with 66.9% of the explained variance related to the characteristics of each microhabitat. The present study results highlight the importance of the microhabitat characteristics for the recruitment processes of reef fish, even at small scales.