Structure of the reef fish community along the depth gradient of the Archipelago Fernando de Noronha, Brazil

• Grant number: 24/13716-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2025
• End date: June 30, 2025
• Field of knowledge: Biological Sciences - Ecology - Ecosystems Ecology
• Principal Investigator: Hudson Tercio Pinheiro
• Grantee: Sabrina Luiza Rabelo
• Host Institution: Centro de Biologia Marinha (CEBIMAR). Universidade de São Paulo (USP). São Sebastião , SP, Brazil
• Associated research grant: 19/24215-2 - Biodiversity, biogeography and conservation of mesophotic coral ecosystems in the Atlantic Ocean, AP.BTA.JP

Abstract

The Fernando de Noronha Archipelago, harbors the most diverse ichthyofauna of the oceanic islands from the Southwestern Atlantic ocean. The archipelago is inserted in a mosaic of Conservation Units (UCs), including a UC of sustainable use, where fishing is allowed, and a UC of integral protection that covers 70% of the main island and all the smaller islands, with limit demarcated by the 50 m isobate. So far, studies of the structure of the reef fish communities of Fernando de Noronha were limited to shallow reefs, not exceeding the 20 m isobate in their sampling areas. A recent survey of shallow fish assemblages (d 30 m) and mesophotic fish (31 to 150 m) from the archipelago revealed an 8.2% increase in the richness of species recorded in the region. Notably, 74% of new species records were obtained in mesophotic ecosystems. Mesophotic reefs are complex ecosystems, with unique communities, but still little known. Understanding the structure of fish communities is fundamental to the management and conservation of reef ecosystems. Therefore, the project aims to understand if and how variations in the ecological characteristics of the reef fish community (richness, abundance and biomass) occur. For this project, a database of underwater visual censuses will be used, distributed along a wide depth gradient (from 3 to 120 m). The results produced will expand ecological knowledge covering mesophotic ecosystems, not covered by the UC of integral protection, allowing a broader look at the management and protection levels established to the protected marine areas that make up the region.