Testing trophic stochasticity in tropical streams through allometric relationships

• Grant number: 20/07522-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2021
• End date: December 31, 2021
• Field of knowledge: Biological Sciences - Ecology - Ecosystems Ecology
• Principal Investigator: Victor Satoru Saito
• Grantee: Jean Barbosa Leal
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The metabolic theory of biodiversity is one of the main theories that seeks to explain ecosystem patterns. In this project, we will seek to apply it to community ecology to assess the niche overlap in tropical stream fish biota, potentially influenced by stochastic processes due to the high metabolism of tropical regions. We will seek to elucidate the influence of stochasticity in the selection of prey through metabolic theory, justifying the possibility that the main food discrimination is due to body proportion. For this purpose, we will use data from a collection of neotropical and invertebrate fish already carried out in the municipality of Cananéia-SP. We will analyze the stomach content of the predatory fish communities, as well as quantify the biomass and characterize the collected individuals functionally. From these data, we will use the classic Pianka index to develop null allometric models that simulate hypothesized food stochasticity. Our general hypothesis is that the high metabolism of tropical systems forces individuals to have a generalist and non-selective diet, depending on the stochasticity of encounters with prey.