Mapeamento do perfil térmico corpóreo durante atividade de voo do beija-flor (Eupetomena macroura)

• Autor(a) principal: Pereira, Moreno [UNESP]
• Data de Publicação: 2017
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/156465; http://www.athena.biblioteca.unesp.br/exlibris/bd/capelo/2018-04-26/000898185.pdf
• topic: Fisiologia; Ave - Vôo; Temperatura corporal - Regulação; Termografia; Beija-flores

Hummingbirds are small sized birds characterized by their elongated beaks, iridescent feathers, and incredible flight capacity. Their flight is sustained by several anatomical and physiological specializations that have a high energetic cost. This entails a high energetic metabolism that significantly increases metabolic heat production and requires an effective mechanism to dissipate this excessive heat. Hummingbirds' thermal windows are responsible for controlling that, they are the main places of heat exchange between them and the surrounding environment. In this sense, the thermoregulation mechanism in hummingbirds proves to be a challenge, since they need an efficient structure able to dissipate the heat accumulated due to their high energy flight metabolism, but also conserve heat and avoid lethargy during the periods they are not at flight. The focus of this study is to understand how the dynamics of heat exchange between bird and environment happens, and its exactly location through the usage of thermal images which reflect superficial temperatures on the animal's body. Using those thermographs, we analyzed the bird's main body regions involved in temperature equilibrium. The results showed that the eyes region is not controlled by the animal, and it is responsible for an intense heat dissipation. It also likely reflects the body temperature of these birds. On a different note, other regions such as beak, head, chest and legs seems to be dynamic regions that undergo alterations according to environmental temperature, having great potential to be thermal windows. The axial area has a great potential of heat exchange in both species and it needs to be better analyzed. Moreover, different species of different sizes had the same thermal profile response in relation to changes in the environment