Seasonal variation in daily activity patterns of snow leopards and their prey

Abstract

The daily and seasonal activity patterns of snow leopards (Panthera uncia) are poorly understood, limiting our ecological understanding and hampering our ability to mitigate threats such as climate change and retaliatory killing in response to livestock predation. We fitted GPS-collars with activity loggers to snow leopards, Siberian ibex (Capra sibirica: their main prey), and domestic goats (Capra hircus: common livestock prey) in Mongolia between 2009 and 2020. Snow leopards were facultatively nocturnal with season-specific crepuscular activity peaks: seasonal activity shifted towards night-sunrise during summer, and day-sunset in winter. Snow leopard activity was in contrast to their prey, which were consistently diurnal. We interpret these results in relation to: (1) darkness as concealment for snow leopards when stalking in an open landscape (nocturnal activity), (2) low-intermediate light preferred for predatory ambush in steep rocky terrain (dawn and dusk activity), and (3) seasonal activity adjustments to facilitate thermoregulation in an extreme environment. These patterns suggest that to minimise human-wildlife conflict, livestock should be corralled at night and dawn in summer, and dusk in winter. It is likely that climate change will intensify seasonal effects on the snow leopard's daily temporal niche for thermoregulation in the future.

Whispers in the snow: unveiling the spatio-temporal snow leopard (Panthera uncia) territorial marking and cub observations for conservation in Baltistan

“…In our study, we analyzed the temporal marking activity patterns of snow leopards during day and night in relation to the presence or absence of snow cover. This comparison was done by tting non-parametric kernel density functions using the "Overlap" package with default bandwidth parameters, as recommended by (Johansson et al, 2022;Li et al, 2023). Circular density curves were used to compare the patterns, and the coe cient of overlap (∆4) was calculated, ranging from 0 (no overlap) to 1 (complete overlap), following the method proposed by (Johansson et al, 2022;Yang et al, 2018).We estimated the overlap coe cient (∆4) for the temporal marking activity of snow leopards in the presence or absence of snow cover and during day versus night events for each communication behavior.…”

“…We divided the winter season into two distinct periods: one characterized by extreme cold temperatures and snow cover from December 25th to February 25th, and the other by warmer temperatures without snow in November, March, and April. These factors are known to impact the temporal activity patterns of snow leopards (Johansson et al, 2022). Additionally, we noted whether there were male or female snow leopards rearing cubs or not.…”

“…The sunrise and sunset times vary slightly throughout the year based on the distance from the equator and the time of year. To adjust for these variations in daylight hours over the year (Johansson et al, 2022), we utilized the "sunTime" function of the "overlap" package version 0.3.2 in R to convert times to radians for analysis(refer to (Johansson et al, 2022) for detailed information).The marking activity events in snow leopard videos were recorded separately for day or crespecular and nighttime for each communication behavior, considering the presence or absence of snow .The marking activity events in the video of snow leopard was recorded independently both for day and night-time for each communication behaviours during presence and absence of snow.…”

“…Communication within a species is a fundamental component of behavioral ecology, with the effectiveness of communication directly in uencing the tness of individuals (Allen et al, 2016b). The communication activities of apex predators are crucial for maintaining ecosystem structure by regulating food chains in mountain landscapes (Johansson et al, 2022). However, these apex predators are globally experiencing rapid range contractions due to human activities such as land-use changes (Buzzard et al, 2017), grazing pressure (Li et al, 2023), poaching (Hacker et al, 2021;Li and Lu, 2014), retaliatory killings related to livestock damages, and the fur trade (Ahmad et al, 2022;Li and Lu, 2014).…”

The influence of climate and the presence of predators on the daily activity pattern of collared peccaries (Dicotyles tajacu, Cetartiodactyla)

“…We used the sunTime() function from the ‘overlap’ package to convert the ‘clock times’ according to the specific periods of sunrise and sunset, the so‐called ‘sun time’, considering the changes in the position of the sun throughout the year (Figure S1). It has been clearly shown that for animals with diurnal variation in activity patterns in seasonal environments, times of observation should be converted to ‘sun times’ so that all observations across the year are calibrated to sunrise, sunset and the sun's zenith (Johansson et al., 2022; Nouvellet et al., 2012; Pasa et al., 2022). Thus, all further analysis were conducted using the ‘sun time’ rather than the ‘clock time’.…”