Social Sciences, University of Toronto-Scarborough
Saturday 1:30-1:45, Grand Ballroom II
Among nocturnal and cathemeral primates, moonlight increases nocturnal activity in many, but not all, species (Nash, 2007). This study investigated the relative effects of moonlight versus mating on night ranging behavior in ring-tailed lemurs. Although this strepsirhine has traditionally been considered diurnal, recent work has demonstrated that ring-tailed lemurs can show nocturnal ranging during mating periods (Parga, 2011). In this study, 6 ring-tailed lemurs from 3 social groups on St. Catherines Island, Georgia, USA were fitted with GPS (Global Positioning System) collars that collected location data once every 30 min. The lemurs were collared during a full moon (several days before the start of mating) in October 2010, and the collars were removed approximately 3 weeks later. To collect data on mating during the collar deployment period, daily dawn to dusk observations were conducted. Results revealed that night (between 1900-0530) ranging distances in the pre-mating period during peak moonlight (90-100%) were significantly longer than distances traveled during the mating period (Mann-Whitney: p<0.05), when the fraction of moon illuminated steadily decreased from 83 to 0%. Furthermore, across the study period, total distance traveled per night positively correlated with the fraction of moon illuminated (Spearman: p<0.0001). In conclusion, as is the case for many cathemeral primates, moonlight stimulates night activity in ring-tailed lemurs. Moreover, moonlight has a stronger positive effect on night ranging than does mating activity. These data provide further evidence of night ranging in this species, strengthening the suggestion that the ring-tailed lemur should be classified as a cathemeral strepsirhine.