Behaviors in rhesus monkeys (Macaca mulatta) associated with activity counts measured by accelerometer

Abstract

There are large individual differences in the daily pattern and level of physical activity in humans and other species. As it is becoming apparent that activity plays an integral role in a number of physiological processes including arousal, attention, cardiovascular health and body weight regulation, there is an increased interest in quantifying activity. Nonhuman primates are particularly useful experimental models for such studies in that they exhibit a repertoire of activity more similar to humans than the activity of animals such as rodents and domestic animals. Recent studies measuring activity in nonhuman primates have used omnidirectional accelerometers, often worn on collars; however, the exact behaviors and movements detected by monkeys wearing these devices have not yet been characterized. To test the hypothesis that collar-worn accelerometers primarily detect movements that involve movement of the whole body, 16 adult female rhesus monkeys, housed individually in stainless steel cages, wore loose-fitting collars with an attached small metal box housing an activity monitor (Actical omnidirectional accelerometer; MiniMitter Inc., Bend, OR) and behavior was videotaped. Videotaped behaviors were analyzed by frame-by-frame analysis. There was a significant correlation between total (all) movement revealed by videotape analysis and activity counts detected by the accelerometers (r(s)=0.612, P=0.012), primarily reflecting a strong correlation between whole body movement and activity counts (r(s)=0.647, P=0.007). In contrast, arm movement (r(s)=-0.221, P=0.412) and head/neck movement (r(s)=0.193, P=0.474) were not correlated with activity counts. These findings support the hypothesis that activity monitor placement on a collar allows for effective quantification of whole body movement in monkeys, and indicate that behaviors such as chewing and arm movement do not significantly influence activity recorded by collar-mounted accelerometers.

Identification of behaviours from accelerometer data in a wild social primate

“…Differentiating between active and inactive behaviours is commonly done with variables such as VeDBA or VeDBAs [1,7,18,24]. Interestingly, static acceleration metrics are not always included as discriminators in machine learning algorithms [30] and so our findings suggest that this could be an important factor for other primate researchers to include in their models.…”

“…The list that follows summarises each of these variables, which are numbered 1-25 in round parentheses: (1-3) tri-axial static acceleration [1]; (4-5) pitch and roll [1]; (6) vectorial dynamic body acceleration (VeDBA); (7) smoothed vectorial dynamic body acceleration (VeDBAs) [35,36]; (8-10) tri-axial partial dynamic body acceleration (PDBA) [1]; (11-13) the tri-axial PDBA-to-VeDBA ratio. In addition to these descriptive statistics, we processed the dynamic part of the acceleration further by computing its (14-16) tri-axial power spectrum density (PSD); (17)(18)(19)) maximum frequencies associated with the triaxial PSDs; (20)(21)(22) the second maximum frequencies associated with the tri-axial PSDs; (23-25) the associated frequency for each axis. We provide a full description for each of these variables (1-25), in turn, below.…”

“…In particular, three-dimensional accelerometers have been used to reconstruct animal behaviour [1,3]. The use of accelerometers has been used most widely in studies of marine mammals and birds [3,4], but recent advances in bio-logging technologies have made devices smaller, cheaper and longer-lasting, drawing interest activity, rather than specific behavioural states (rhesus monkeys, Macaca mulatta [18], vervet monkeys, Chlorocebus pygerythrus [19] and owl monkeys, Aotus azarai [20]). To our knowledge, the only study that has used accelerometers to identify specific behaviour was undertaken by Sellers and Crompton [21] where they successfully identified locomotion events in captive red-ruffed lemur (Varecia variegata rubra).…”

Jumping in the Night: An Investigation of the Leaping Activity of the Western Tarsier (Cephalopachus bancanus borneanus) Using Accelerometers

“…In recent times, there has been a growing interest from primatologists in accelerometers, but the number of studies carried out on free-living animals is still limited Crompton, 1994, 2004;Mann et al, 2005;Sullivan et al, 2006;Papailiou et al, 2008;Ravignani et al, 2013;Wunderlich et al, 2014]. Prior work on primates found that accelerometers can enable investigators to collect valuable information about the behaviour and ecology of a given species.…”

Evaluating the utility of an accelerometer and urinary hormone analysis as indicators of estrus in a Zoo‐housed koala (Phascolarctos cinereus)

“…A novel technique to record the activity of animals involves the use of an accelerometer. Although traditionally used in human medicine, accelerometers have been found to successfully monitor gross motor movement of animals [Mann et al, 2005;Papailiou et al, 2008].…”