Influence of predation risk and plant structure on vigilance and intermittent locomotion in <Emphasis Type="Italic">Microcavia australis</Emphasis> (Rodentia,Caviidae)

The aim of this study was to analyze and compare vigilance behavior and intermittent locomotion at two sites (El Leoncito and Ñacuñán, Argentina) that differ in predation risk, plant structure, and plant resource availability. Subjects were lesser cavies (Microcavia australis), a social species that is semi-fossorial, diurnal, and native to South America. Continuous focal sampling was conducted during the day, at times of food shortage, food abundance, and reproduction from 2003 to 2005. The proportion of time spent vigilance was significantly higher at Ñacuñán, where vigilance peaked at midday and reached a minimum in the evening. This midday peak of vigilance at Ñacuñán was associated with a midday peak of danger from raptors as indicated by a raptor activity peak at that time. In contrast, both vigilance and predator activity at El Leoncito were constant through the day. Records of intermittent locomotion and number and duration of pauses in locomotion were significantly higher at El Leoncito, a difference that may have been due to the need for greater vigilance while moving across areas of less protective cover at this site.