Not everything must end in a fight: how does the color of light influence the behavior of the matrinxã Brycon amazonicus?

• Grant number: 22/11942-6
• Support Opportunities: Scholarships in Brazil - Program to Stimulate Scientific Vocations
• Start date: January 04, 2023
• End date: February 23, 2023
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Adalberto Luis Val
• Grantee: Caio Augusto Paula
• Host Institution: Instituto Nacional de Pesquisas da Amazônia (INPA). Ministério da Ciência, Tecnologia e Inovação (Brasil). Manaus , SP, Brazil

Abstract

The matrinxã is of interest to fish farming in the Amazon and is recognized for its aggressive behavior from the early stages of development, which implies significant losses, as the number of individuals that reach adulthood is reduced. Recent studies have sought to find ways to control aggressiveness and cannibalism in the species with the aim of increasing production levels and safeguarding adequate supply to the consumer market. Light has been a focal target in these researches, as it modulates the responses of the biological cycle and induces physiological events that can help to improve the behavior of the species. Variations in quantity (photoperiod and luminous intensity), quality (spectrum, radiation by emitting diode - LED, fluorescence and incandescence), as well as their combinations are among the most applied tools. Results with matrinxã indicate that low light intensity stimulates the reduction of aggressive behavior. Thus, the study will aim to answer whether different light spectra (colors) induce aggressiveness in the species through behavioral assessment. The student will develop an experiment, where he will expose juvenile individuals of the species in aquariums (10L), in pairs, inside closed structures coupled with LED lamps, which will represent five light spectrums (blue, green, yellow, red and white ), plus darkness. In these structures the animals will be acclimatized and then exposed daily to a period of 12h-light:12h darkness, for 3 days, with the respective spectra for which they were drawn. Filming will be carried out for 10 minutes each day of exposure, repeated eight times in each spectrum, using cameras that will be installed inside structures that will be free from contact with external lighting. The agonistic behaviors will be evaluated, through the visual analysis of the generated videos. Behaviors will be broken down by standardized ethological scale. (AU)