New publication: A contemporary baseline of Madagascar’s coral assemblages

New article published

Mahery Randrianarivo, François Guilhaumon, Johanès Tsilavonarivo, Andriamanjato Razakandrainy, Jacques Philippe, Radonirina Lebely Botosoamananto, Lucie Penin, Gildas Todinanahary, Mehdi Adjeroud (2022) A contemporary baseline of Madagascar’s coral assemblages: Reefs with high coral diversity, abundance, and function associated with marine protected areas. PLoS ONE 17(10): e0275017.

Published: October 20, 2022

Download from : https://doi.org/10.1371/journal.pone.0275017

 

During many years of studying coral reefs, none have rigorously analyzed Madagascar’s coral assemblages at multiple spatial scales, and the effects of marine protected areas or other drivers like geographic location, abiotic/biotic factors on these latter are poorly known.

In this study, we focused our efforts at 18 sampling stations equally distributed over 3 regions around Madagascar where reefs are the most developed (Masoala in NE, Nosy-Be in NW and Salary Nord in SW). Half of stations in each region are established in unfished area and the other half in fished ones.

We found a marked spatial variability of these assemblages, with variation at either or both regional and local scales for all coral descriptors. The northeast coastal region of Masoala was characterized by the high abundance of coral colonies, most notably of the competitive Acropora and Pocillopora genera and stress-tolerant taxa at several stations. The southwest station of Salary Nord was distinguished by lower abundances, with depauperate populations of competitive taxa. On the northwest coast, Nosy-Be was characterized by higher diversity and abundance as well as by high coral cover (~42–70%) recorded at unfished stations. Marine reserves in MPAs had a positive effect on almost all coral descriptors, with a more pronounced effect in Nosy-Be. Apart, we found that herbivorous fish biomass, crustose coralline algae cover and substrate rugosity also have this positive effect, unlike for macro and turf algae cover.

With our findings, we support the fact that MPAs was a useful coral reef management tool. With more details in this paper, readers could see that reefs in Masoala are initially resilient, those in Nosy-Be are among the priorities of conservation and those at Salary Nord were highly disturbed.

Location of the 18 sampling stations in the three regions around Madagascar. Masoala (A) is located in the northeast coast, Nosy-Be (B) in the northwest, and Salary Nord (C) in the southwest. See Materials and Methods section for station codes.

https://doi.org/10.1371/journal.pone.0275017.g001

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