Comportamento territorial de Lipaugus lanioides (Aves: Cotingidae) em área de Floresta Atlântica na Ilha Grande, RJ

Abstract

Territorial behavior is a strategy to monopolize resources when these are important to reproductive success of an organism. A territory is an exclusive area, defended against intruders and same sex coespecific, coming from social interactions between neighbors. Territorial behavior performs an important role in a reproductive system species as well, because it influences male contribution on reproduction. In these cases, females can get direct benefits, as nesting sites and parental care. Territoriality also interferes in population size through a costs and benefits relation: on ideal environments and highly population density, territories are small and there are few substitutions because young males have difficulties to establish territories themselves. This present study researched behavioral aspects of Cinnamon-vented Piha, an endemic and rare Atlantic forest species, with restrict distribution. Throughout 18 months at Ilha Grande, RJ, we investigate its territorial behavior, measured male s individual territories sizes and estimated population density. A playback was played to attest territoriality in species, simulate coespecific approaches (intraspecific interactions) and encourage individual displacements to their territories boundaries. To investigate behaviors responses to intruders invasions, we quantified males reactions to sonorous stimulus (spontaneous and induced vocalizations by playback). Their territories were defined during two reproductive periods by Minimum Convex Polygon (MCP) at an area equivalent to 20ha. Population density was defined by the number of territories found and the number of individuals seen/heard at an area unit by linear transections. On this period, males became solitary and aggressive with coespecific; in non-reproductive phase, however, they stood sociable, foraging in small groups up to four individuals. The results suggest that territories are established to monopolize food and access to females, therefore this studied species is territorialist. In total, seven territories were estimated with values between 0,21ha e 0,73ha (0,43 + 0,16ha). Individuals display territorial fidelity, preserving their territories along two reproductive seasons. L. lanioides population density ranged along the year showing highest values on reproductive season (0.37 and 1.84 individuals/ha). Fluctuations in population density can aim to altitudinal migrations motivated by variations of food resources availability. L. lanioides reproductive behavior does not fit in the reproductive leks system concept, attested in some other cotingas (eg. Lipaugus vociferans), in which courtship is a social behavior, with contests for dominance status, and male roles is restricted to copula without direct benefits for females. In this way, our results bring original information about L. lanioides biology