Monitoring rocky reefs of the North Coast in the State of São Paulo: Palythoa caribaeorum bleaching and anthropic stressors

• Grant number: 22/05518-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: September 01, 2022
• End date: August 31, 2024
• Field of knowledge: Biological Sciences - Ecology - Applied Ecology
• Principal Investigator: Denis Moledo de Souza Abessa
• Grantee: Amanda Escarabichi Bueno Mariano
• Host Institution: Instituto de Biociências (IB-CLP). Universidade Estadual Paulista (UNESP). Campus Experimental do Litoral Paulista. São Vicente , SP, Brazil

Abstract

The reefs ecosystem has ecological and socioeconomic importance. However, the capacity of these environments to provide ecosystem services has declined since 1950 due mainly to anthropic actions. The zoanthid Palythoa caribaeorum, an important structuring of the benthic community, occurs widely in the rocky reefs of the North Coast of the State of São Paulo. This region is in an accelerated urbanization process and generates a flow of 4 million tourists/year. High bleaching rates of P. caribaeorum were recorded in the rocky reefs of Ubatuba, SP., and the worst scenario was found on Ilha das Couves, a Special Management Area within APAMLN, however, there are still few efforts to monitor zoanthid colonies in rocky reefs, compared to scleractinian corals and biogenic reefs. This study aims to understand whether activities related to tourism and urbanization influence the bleaching of P. caribaeorum, especially on the Ilha das Couves and whether bleaching is more intense than in other regions of the coast of São Paulo and on islands more distant from the coastline. It will be studying the rocky reefs present in Ilha das Couves, Ilha do Prumirim, Ilha das Palmas, Ilha das Cabras and Arquipélago dos Alcatrazes. Beyond the colonies of P. caribaeorum, it will be sampled other two species that occur in the region (Mussismilia hispida and Madracis decactis) for comparison, in 4 seasonal campaigns, using transects where photos will be made through sample squares. Physicochemical analyses of water samples will be made and degree heating weeks (DHW) values will be obtained for the study regions. For each site will be recorded the number of visitors, bathers, divers, and boats to calculate the Relative Environmental Pressure Index (REPI). Coral Health Chart will be used for bleaching analysis. The bleaching data from each site will be compared through ANOVA. The same point over the 4 campaigns will be compared by a GLM of repeated measures. Correlations will be made between abiotic data, anthropic activities, and bleaching. This project will expand the P. caribaeorum monitoring started in 2021 in the Ubatuba region. All study sites are inserted in Marine Protected Areas, where the monitoring of species and environmental health is necessary, among them the Ilha das Couves, a place that has been studied to generate data for the ordering of tourism. (AU)