Biometria, bionomia e ecologia de aves em áreas de cerradão na Floresta Nacional do Araripe - FLONA Araripe, Ceará, Brasil

Abstract

This study evaluates biological and ecological characteristics of the avian fauna present in areas of the National Forested Savanna (Cerradão) of Araripe, Ceará (FLONA). The major objectives are: describe the avian fauna composition and frequency of occurrence of species, classify species as to their ecological attributes, investigate both bionomics and biometrics data and finally, test the following hypotheses: (i) a relationship exists between the change of seasons (dry and rainy season) and observations of changes in breast plate plumage of the species caught and (ii) phenotypic variations exist in those species captured that have sexual dimorphism.. Data collection occurred through mist net capture of individuals, direct visual and auditory observations as well as use of the Mackinnon method. Between December 2011 and November 2012 116 species (48 families) were recorded and 583 individuals belonging to 59 species of 24 families were captured, with a sampling effort of 91,140 m2.h. In addition to recovery of leg bands fitted in the current research a leg band from a previous study was also retrieved (Neopelma pallences with a leg band duration of 18 years). The species with the highest frequency of occurrence were Thamnophilus pelzelni (57.4%), Turdus leucomelas (53.6%), Tangara cayana and Euphonia chlorotica combined (41.3%). The vertical stratification of vegetation occupied by the avian fauna was medium to high and the social status most observed was of solitary individuals. Regarding eating habits, there was a predominance of insectivorous birds followed by fruitarian birds. A significant number of birds which are indicators of good environmental quality, as well as species sensitive to disturbance, were visualized. The relationship between seasonality and pattern of changes in breast plate plumage in species caught was evident. There was no significant weight difference in species with sexual dimorphism to biometric data, only a case of the wing length of Tangara cayana which was significant. The results infer that the FLONA is in a good state of conservation and containing a high diversity of avian fauna. Studies such as this, in addition to implementing literature with biometrics and bionomic data about species, corroborate the formation of management plans in areas of forested savanna, presently severely degraded due to anthropic actions.