Trophic ecology and snake diversity in an agroecosystem

• Grant number: 23/11463-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2024
• End date: June 30, 2025
• Field of knowledge: Agronomical Sciences - Forestry Resources and Forestry Engineering - Nature Conservation
• Principal Investigator: Katia Maria Paschoaletto Micchi de Barros Ferraz
• Grantee: Caio da Silveira Nunes
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Snakes are important population regulators in ecosystems and bioindicators. Despite this, they still lack a set of conservation and management initiatives. The anthropization of natural areas is one of the main threats to these animals, for example, in the Atlantic Forest, which has historically suffered from deforestation. Thus, this study aims to: 1) carry out an inventory of snakes occurring in an agroecosystem, 2) analyze the species and functional diversity of snakes at the site and 3) investigate the trophic ecology and resource use of snakes. The study will be carried out on the USP "Luiz de Queiroz" campus (Piracicaba, SP), where the presence of snakes in anthropic areas has been very frequent. The USP "Luiz de Queiroz" campus is an agroecosystem with different types of land use, where open grassy areas, agricultural plantations (corn and soybeans), forest fragments and riparian corridors predominate, as well as buildings and public roads. Individual snakes will be captured through active searching in different components of the campus landscape. Once captured, individuals will have scales and blood collected for isotopic analysis, feces for identification of food resources, as well as ectoparasites for identification. Individuals accidentally captured in buildings and public roads will also be used to collect samples, a fact that has been occurring frequently on campus. Individuals captured in natural environments will be microchipped, have their morphometric measurements collected, and will be released in the same location. Accidentally captured individuals will be translocated to a safe location, using the shortest translocation distance possible, to guarantee the animal's well-being and prioritizing environments that the species would naturally occupy. The trophic ecology will be analyzed by fecal content and complemented using the stable carbon and nitrogen isotopes tool, using the CF-IRMS technique (Continuous Flow - Isotope Ratio Mass Spectrometer). Functional diversity will be analyzed using functional richness (FRic), functional uniformity (FEve) and functional dispersion (FDis) indices, while taxonomic diversity will be analyzed using alpha diversity using the rarefaction curve technique. This study is expected to expand the understanding of how snakes explore modified environments and may support monitoring and conservation plans for snakes in anthropic landscapes.