Influence of birds’ reproductive period on body condition of Antilophia galeata (Passeriformes: Pipridae)

A bird’s reproductive period is indicated by the presence of brood patches, and is a period of higher energy demand. The accumulation of body fat to provide the energy required in this period can be achieved by the bird’s diet. The Relative Body Mass Index (BMI) is a tool capable of assessing the body’s condition by estimating the nutritional reserves, which is based on the biomass and on a measurement of the bird’s body length. In this regard, the present study aimed to compare BMI values between individuals with and without brood patches. Ninety individuals of Antilophia galeata were captured from June 2013 to December 2015 in a semidecidual seasonal forest fragment in the Triângulo Mineiro, Minas Gerais, Brazil. In order to confirm the presence/absence of brood patches a modified scale of Wild Birds Banding Manual has been applied. The BMI was calculated by a Simple Linear Regression between the logarithmic values in the base ten of the biomass and the length of the right tarsus. There was no significant difference in the BMI values among individuals with and without brood patches (t = -0.578; df = 88; Prob = 0.565). This result can be related to the fact that Antilophia galeta is a non-migratory species and also that the studied area does not offer a constant supply of food resources. Therefore, it is concluded that the reproductive period did not affect the body condition of individuals of A. galeata.