Effect of the insecticide Fipronil on the hatching of dormant egg banks of Zooplankton (Cladocera, Copepoda, and Rotifera).

• Grant number: 24/02118-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date until: June 01, 2024
• End date until: May 31, 2025
• Field of knowledge: Biological Sciences - Ecology - Applied Ecology
• Principal Investigator: Jorge Laço Portinho
• Grantee: Marco Antônio Azevedo Machado
• Host Institution: Faculdade de Ciências e Letras (FCL-ASSIS). Universidade Estadual Paulista (UNESP). Campus de Assis. Assis , SP, Brazil

Abstract

Currently, the majority of freshwater environments are threatened by contamination from chemical pollutants. Understanding the influence of these contaminants is important to ensure the conservation of aquatic biodiversity and the maintenance of ecosystem services that these water bodies provide to humans. Zooplankton (Cladocera, Copepoda, and Rotifera) can produce dormant eggs (i.e., a cluster of unhatched eggs deposited at the bottom of pond sediment), which play a crucial role in the regeneration and maintenance of diversity in aquatic ecosystems. To the best of our knowledge, no study in Brazil has assessed the influence of the insecticide Fipronil on the hatching and subsequent life cycle of invertebrates hatched from dormant eggs. This lack of information poses serious challenges for implementing practical measures for the recovery of polluted aquatic ecosystems. In this project, hypotheses will be investigated, namely: (i) exposure of dormant eggs to Fipronil reduces abundance and diversity, and (ii) it produces adverse effects on the life cycle of hatched organisms. To test these hypotheses, hatching experiments will be conducted in the laboratory, where sediments from natural ponds containing dormant eggs will be exposed to different contaminants. At the end of the experiment, the biological response of the hatched zooplankton exposed to Fipronil will be compared with that of a control treatment. The project's theme can be considered an extension of the recently approved project by the responsible professor (advisor) on the effect of chemical contaminants on the viability of dormant stages (CNPq/MCTI Call No. 10/2023 - Range A - Emerging Groups, Universal 2023 - process No. 402680/2023-5), and in collaborations on projects carried out in recent years funded by Fapesp (2021/00619-7 and 2019/06291-3). Therefore, this proposal is a natural and necessary consequence of previous projects. In addition to the planned outcomes, our primary goals are: (a) to understand the impacts of the insecticide Fipronil on the hatching and subsequent life cycle of zooplankton hatched from dormant eggs; (b) to encourage the formation of excellence and the development of young scientists.