Effects of temperature in reproduction and dispersion of the Sun Coral, Tubastraea coccinea

• Grant number: 17/04904-2
• Support type: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): February 01, 2020
• Effective date (End): January 31, 2022
• Field of knowledge: Biological Sciences - Ecology - Ecosystems Ecology
• Principal Investigator: Augusto Alberto Valero Flores
• Grantee: Damian Mizrahi
• Home Institution: Centro de Biologia Marinha (CEBIMAR). Universidade de São Paulo (USP). São Sebastião , SP, Brazil

Abstract

The Sun-Coral Tubastraea coccinea is a predominantly tropical invader that releases larvae massively during short events at different times each year. These events occur both in summer and winter in populations near this species geographic distribution limit, such as those previously examined in the State of São Paulo, Brazil. However, different previous studies had reported significant effects of temperature in the reproduction of the Sun-Coral, indicating higher reproductive output in warmer waters. The present proposal aims to investigate the effect of the temperature of the water column on the larval production and performance of initial pelagic and benthic phases of the Sun-Coral. In a first experiment, temperature treatments (T1: 18-20ÚC and T2: 26-28ÚC) will be applied to mature coral colonies to test the hypothesis that adult colonies manipulate the allocation of resources to the offspring, producing larvae with better physiological conditions and greater dispersive potential in colder waters, which is assumed to be an unfavorable scenario for the development of early recruits. In this experiment, we will quantify the number and size of larvae produced and their content of lipid reserves. A second experiment, with the same thermal treatments applied on pelagic larvae, will enable us to test the hypothesis that low temperatures reduce larval metabolism, increasing its competence window and producing larger recruits. Alternatively, these latter conditions can cause stress on larvae, accelerating their metabolism and leading to opposite effects. The ecological relevance of the results will be evaluated through field surveys of Sun-Coral larval production and its performance in the natural environment. The information generated in this study will allow predicting and categorizing areas susceptible to the invasion of the Sun-Coral, according to their location and climatic parameters, which will subsidize control plans applicable to areas still not invaded by the Sun-Coral. (AU)