Effects of Reproductive Status, Social Rank, Sex and Group Size on Vigilance Patterns in Przewalski's Gazelle

Abstract

BackgroundQuantifying vigilance and exploring the underlying mechanisms has been the subject of numerous studies. Less attention has focused on the complex interplay between contributing factors such as reproductive status, social rank, sex and group size. Reproductive status and social rank are of particular interest due to their association with mating behavior. Mating activities in rutting season may interfere with typical patterns of vigilance and possibly interact with social rank. In addition, balancing the tradeoff between vigilance and life maintenance may represent a challenge for gregarious ungulate species rutting under harsh winter conditions. We studied vigilance patterns in the endangered Przewalski's gazelle (Procapra przewalskii) during both the rutting and non-rutting seasons to examine these issues.Methodology/Principal FindingsField observations were carried out with focal sampling during rutting and non-rutting season in 2008–2009. Results indicated a complex interplay between reproductive status, social rank, sex and group size in determining vigilance in this species. Vigilance decreased with group size in female but not in male gazelles. Males scanned more frequently and thus spent more time vigilant than females. Compared to non-rutting season, gazelles increased time spent scanning at the expense of bedding in rutting season. During the rutting season, territorial males spent a large proportion of time on rutting activities and were less vigilant than non-territorial males. Although territorial males may share collective risk detection with harem females, we suggest that they are probably more vulnerable to predation because they seemed reluctant to leave rut stands under threats.Conclusions/SignificanceVigilance behavior in Przewalski's gazelle was significantly affected by reproductive status, social rank, sex, group size and their complex interactions. These findings shed light on the mechanisms underlying vigilance patterns and the tradeoff between vigilance and other crucial activities.

Collective Vigilance in the Wintering Hooded Crane: The Role of Flock Size and Anthropogenic Disturbances in a Human‐Dominated Landscape

“…After data collection, we initially checked the video records and discarded those shorter than 1 min to increase data reliability and representativeness (Lung & Childress ; Li et al. ). We also discarded flocks with less than two adults as juveniles are not typically very vigilant in this species (Li et al.…”

“…While taking videos, we recorded contextual information for each focal flock, including flock composition, date and time, disturbances, and habitat type. After data collection, we initially checked the video records and discarded those shorter than 1 min to increase data reliability and representativeness (Lung & Childress 2007;Li et al 2012). We also discarded flocks with less than two adults as juveniles are not typically very vigilant in this species (Li et al 2015).…”

The Time Budget of Javan Deer ( Rusa timorensis , Blainville 1822) in Panaitan Island, Ujung Kulon National Park, Banten, Indonesia

“…Group size effect has been reported in Tibetan antelope (Lian et al 2007), Tibetan gazelle (Li & Jiang 2008), asiatic ibex (Xu et al 2010), svalbard reindeer (Reimers et al 2011), and goitered gazelle (Xia et al 2011). Several hypotheses have been proposed to explain the mechanism of group size effect including: collective vigilance (Ebensperger et al 2006;Pays et al 2007), detection and dilution (Fairbanks & Dobson 2007;Li & Jiang 2008;Li et al 2012), and social facilitation (Michelena & Deneubourg 2011).…”

Costs of mate-guarding in wild male long-tailed macaques (Macaca fascicularis): Physiological stress and aggression

“…In this highly energetically demanding context, cortisol plays a crucial role by stimulating gluconeogenesis and the mobilization of fatty acids from body stores (Sapolsky, 2002). This physiological process might be partly triggered by changes in males' activity budget during the reproductive period whereby males feed less time (see above) and, in some species, spend more time being vigilant (Li et al, 2012;Guillemain et al, 2003;Reboreda and Fernandez, 1997) in order to monitor other males as well as fertile females. This shift in energy budget might represent an energetic challenge since decreased feeding time might lead to reduced energy intake and vigilance enhances energy expenditure (Warm et al, 2008).…”