Edvaldo Silva-Jr

• MSc in Ecology
• University of Brasília

Vocal individuality is essential for social discrimination but has been poorly studied in animals that produce communal signals (duets or choruses). Song overlapping and temporal coordination make the assessment of individuality in communal signals more complex. Additionally, selection may favor the accurate identification of pairs over individuals...

Although hissing is a common strategy of defence used by snakes, especially of the Phytonidae and Boidae families, few studies have described in detail the acoustics components of this behaviour. Here we gathered eight recordings from six different boas from Brazil and extracted acoustic measurements from their hissing sounds. We also examined the...

Animals can encode information within acoustic signals, particularly, bird songs can be remarkably complex and can indicate individual identity and quality. Two main sets of hypotheses attempt to explain the evolution of increased birdsong complexity across large-scale geographic ranges: 1) larger acoustic space availability, and 2) greater sexual...

Within social signaling contexts, behavioral displays used for territorial defense and courtship may be affected by vegetation characteristics and by human disturbance. The primary aim of this study was to evaluate the relation between motor display variables of the blue-black grassquit (Volatinia jacarina) and vegetation characteristics. Secondly,...

The weekend effect hypothesis predicts that weekly cycles of human activity impact animal behaviour and physiology. This hypothesis has been supported in the context of recreational activity in natural environments, but it is unknown whether it also applies to urban animals. We tested this hypothesis by comparing the sentinel (territorial vigilance...

In the tropics, birds produce smaller clutches and have a higher risk of nest predation when compared to those in the temperate region. Consequently, a high annual adult survival and a long lifespan are expected for tropical birds. Although determining longevity is a key step towards understanding the life-history strategies of wildlife, the lifesp...

Gray-hooded Gull, Chroicocephalus cirrocephalus (Vieillot, 1818), is distributed across South America and considered a resident, with individuals in their non-breeding period able to disperse over long distances. We report the first records of this species from the state of Espírito Santo, the only state on the Brazilian coast without previous reco...

Duetting is a collective behavior and might have multiple functions, including joint territory defense and mate guarding. An important step toward understanding the adaptive function of bird song is to determine if and how singing behavior varies seasonally. However, seasonal patterns for duetting species are different from the pattern described fo...