Moyses Barbosa1, Thiago Mendes1, Marcos Bouças1
1Universidade Federal Fluminense, Brazil
Despite their small size, cryptobenthic fishes play a crucial role in reef ecosystems. They act as important consumers of algae, detritus, and benthic invertebrates, serving as prey for larger predators and playing a key role in energy transfer within food webs. However, little is known about the distribution and habitat preferences of Brazilian cryptobenthic reef fishes. Our objective was to assess the distribution of cryptobenthic reef fishes in subtropical rocky reefs under the influence of coastal upwelling. We conducted 124 underwater visual censuses (2 x 20 m) across six locations in two regions of Arraial do Cabo (RJ) with varying levels of exposure to upwelling. In each census, we actively searched for cryptobenthic species, identified and estimated their size, and recorded the substrate where each individual was found. We recorded 22 cryptobenthic species, with Parablennius pilicornis being the most abundant species in locations more influenced by upwelling. Coryphopterus glaucofraenum, Emblemariopsis signifera, and Parablennius marmoreus dominated in sheltered locations. Smaller individuals of P. pilicornis and P. marmoreus were found in algal matrices and macroalgae, while larger individuals occupied encrusting calcareous algae. E. signifera was primarily found on Millepora alcicornis, but also on other corals and epilithic algae. C. glaucofraenum was observed on sand, as well as on epilithic algae and gravel associated with the rocky reef interface. Our results show that the main species use different substrates, potentially as a strategy to reduce interspecific competition for resources. Furthermore, species of the genus Parablennius appear to exhibit ontogenetic variation in habitat use, which may be related to better camouflage for smaller individuals in algae or to territorial disputes among larger individuals.
Biography
Biologist with a master’s degree in Aquaculture and a PhD in Marine Biology. My main interests are ecology and biology of reef fish, fisheries impact, aquaculture, management and conservation of marine biodiversity, with a focus on reef and oceanic environments. I am currently vice coordinator of the Projeto Costão Rochoso, which works on the conservation of different components of the rocky shore ecosystem in the state of Rio de Janeiro.