부산대학교 도서관

Rainfall is often indirectly related to the availability of resources, which in turn regulates the abundance of rodents over time. However, the direct influence of rainfall on daily activity is poorly understood, despite the fact that it likely has a great effect on small animals. Furthermore, the influence of the moon on the movement of rodents has been the subject of debate but limited to studies conducted in open areas. Based on a study using pitfall traps in a subtropical region of southern Brazil, this study aimed to investigate the effects of rainfall and the phases of the moon on the daily movements of five species of sigmodontine rodents in a Neotropical forest. Activity patterns were assessed over 130 days, and the daily rainfall and moon phase were verified. Rainfall exhibited a significant positive effect on all studied species. This reflects an increase in the movement of rodents on rainy days, which should be primarily associated with the immediate harmful effects of rain, such as a wet coat and the destruction of shelters. The five species responded differently to moon phase, with a lack of effect for three of them and a positive effect of a full moon on the activity patterns of the other two species. This increase in activity rhythm due to a full moon may indicate a benefit of clear nights for foraging, in contrast to the most common outcome, which associates the brightness of the moon with increased predation risk.