The Effects of Climate Seasonality on Behavior and Sleeping Site Choice in Sahamalaza Sportive Lemurs, Lepilemur sahamalaza

Abstract

Temperature, rainfall, and resource availability may vary greatly within a single year in primate habitats. Many primate species show behavioral and physiological adaptations to this environmental seasonality, including changes to their diets and activity. Sahamalaza sportive lemurs (Lepilemur sahamalaza) inhabit the northwest of Madagascar and have been studied only during the dry, colder period of the year. We investigated potential effects of climate seasonality on this species by collecting behavioral data between October 2015 and August 2016, encompassing both the warmer wet and the colder dry seasons. We collected 773.15 hours of behavioral data on 14 individual sportive lemurs to investigate year-round activity budgets, ranging behavior, and sleeping site locations. Additionally we recorded temperature and rainfall data at our study site to describe the environmental conditions during the study period. The study individuals significantly decreased their time spent traveling and increased their time spent resting in the dry season compared to the wet season. Although home range size and path lengths did not differ over the study period, sleeping locations were significantly different between seasons as the lemurs focused on more confined areas in colder periods. Overall, the results indicate that Sahamalaza sportive lemur behavior varies with season, in line with reports for other primates.Electronic supplementary materialThe online version of this article (10.1007/s10764-018-0059-1) contains supplementary material, which is available to authorized users.

Spatiotemporal distribution of individuals as an indicator for the social system of Lepilemur sahamalaza

“…While not all individuals inhabiting the forest fragment could be radio‐collared, the high degree of overlap between some of the study individuals, as well as the occurrence of social interactions with uncollared conspecifics throughout the home range, speaks against exclusive pair‐based or solitary home range use. In addition, we did not record any consistent aggressive territory defense in either sex but cannot dismiss that extensive vocal activity, observed in males and females (see Mandl et al, ) or scent marking may have contributed to actively excluding other individuals from a home range (Raemaekers & Raemaekers, ). Overlapping home ranges give indications as to social units within a population (Bearder, ; Müller & Thalmann, ; Sterling & Radespiel, ).…”

“…Maximum temperatures during the day ranged between 21 and 39°C while minimum temperatures recorded at night ranged between 13 and 28°C and there was virtually no rain between April and October. For details on the seasonality in this region see Mandl, Holderied, and Schwitzer (). We collected data for 10 months between October 2015 and August 2016 (no data collection in March 2016).…”

“…Two teams, consisting of three observers respectively, each followed a focal individual simultaneously between 18:00 and midnight, each team using a SIKA radio tracking receiver (Biotrack) and three‐element Yagi antenna (Biotrack). We only collected data in the first half of the night as previous data suggested that there was no difference between activity budgets in the first half compared with the second half of the night (Mandl et al, ). The observers followed the focal individuals and recorded their behavior continuously.…”

“…However, we focused on calculating the home range size, rather than interpreting home range use, for which independence of data points is not necessarily required (Blundell et al, ; De Solla, Bonduriansky, & Brooks, ; Swihart & Slade, ). We do acknowledge that the limited sample sizes may have decreased home range size estimates and that longer data collection period may have given more accurate estimates (see Mandl et al, , the Supporting Information Material for plots of cumulative home range size). The overlap between the 99% home ranges of all neighboring study individuals was calculated.…”

Effects of cold weather on the sleeping behavior of Skywalker hoolock gibbons (Hoolock tianxing) in seasonal montane forest

“…First, both groups stayed in their sleeping trees for longer periods of time during the cold season; a possible strategy to conserve energy. Increased resting during the daytime is a common strategy to cope with the thermoregulatory cost associated with low temperatures (Fan et al, ; Mandl, Holderied, & Schwitzer, ). Although both groups had longer sleeping periods during the cold season, Group NA slept less compared to Group BB.…”