Primary and secondary sex-ratio in wild populations of Anodorhynchus leari (Birds, Psittacidae) and implications to populations dynamics

• Grant number: 23/09771-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2023
• End date: July 31, 2024
• Field of knowledge: Biological Sciences - Zoology
• Principal Investigator: Luís Fábio Silveira
• Grantee: Daniele Rodrigues Costa
• Host Institution: Museu de Zoologia (MZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The Lear's Macaw Anodorhynchus leari (Bonaparte, 1856), is currently listed as "Endangered" by IUCN and ICMBio. Is endemic to northeastern Brazil, with its area of occurrence inserted in the morphoclimatic domain of the Caatinga, and the population concentrated in the Raso da Catarina and Depressão Sertaneja Meridional ecoregions. It's a long-lived and monogamous species, with late sexual maturity, and therefore, the number of individuals of each sex in the population acts as a limiting factor in the demography of the species. This study aims to verify the existence of sex-ratio biases of the offspring of natural populations of Lear's Macaw, and to investigate its implications for the population dynamics of the species.