Guardian of the fields: a study on the behavior of the Southern Lapwing Vanellus chilensis (Aves: Charadriiformes) in Southern Brazil

ABSTRACT The Southern Lapwing Vanellus chilensis (Molina, 1782) is a common bird in Rio Grande do Sul state, south Brazil, but is widely distributed across South America. It inhabits grasslands and other open habitats and it is known by a distinctive black, grey, and white coloration, a conspicuous vocalization and both aggressive and territorial behaviors. Although being recognized as the bird symbol of Rio Grande do Sul, no study about its behavior has yet been carried out in the state. Here, we aimed to describe and quantify the behavioral repertoire of Southern Lapwing. Between December of 2017 and November of 2018, we carried out observations in an eight-hectares grassland site in northern Rio Grande do Sul. We used ad libitum and animal focusing techniques to identify and record the frequency and duration of specific behaviors. An ethogram was elaborated, representing the 23 detected behaviors, grouped in five categories: locomotion, maintenance, feeding, socio-agonistic, and reproduction. Our analysis showed that most behaviors vary in both frequency and duration over the year. We detected high frequency and duration of social-agonistic and reproductive behaviors during the breeding season, while other categories, like feeding and maintenance, showed a decrease in the same period, with greater commitment to protect the eggs and chicks. We also recorded three types of vocalization with different characteristics, one of which occurs exclusively during the breeding season. The results of our study allowed the identification and quantification of V. chilensis in southern Brazil, thus helping in understanding the relations between the species and its habitats in the region.