Effect of sex, age, and reproductive status on daily activity levels and activity patterns in jaguars (Panthera onca)

Influence of season, sex, and interspecific interactions on the diel activity patterns of two sympatric African small carnivores

Animal activity patterns vary seasonally and between species, facilitating species coexistence. In Africa, however, factors affecting the activity of many small carnivores remain poorly understood, especially for congeneric and sympatric species whose similar sizes may lead to interspecific competition. Here, we investigated differences and variations in the activity patterns of two sympatric Viverridae species in a seasonal African landscape. We continuously radio-tracked 15 small-spotted genets (Genetta genetta) and five Cape genets (G. tigrina) over 24-h cycles throughout the year. We analysed the effects of season, sex, and interspecific interactions on circadian rhythms using multi-cosinor regression models. Both species maintained a nocturnal activity pattern year-round, decreasing activity significantly during the cold-dry season. This pattern aligns with the thermoregulatory hypothesis-especially for species with an elongated body like genets-suggesting decreased activity under extreme cold weather conditions to conserve energy. Females in both species were less active than males, possibly due to their smaller home ranges, especially during the cold-dry season. These effects were particularly pronounced in Cape genets, which primarily inhabit riverine forests. Female Cape genets adjusted their activity onset, possibly to minimize encounters with males, mostly during the hot-wet season when caring for their offspring. Small-spotted genets shifted their activity onset and peak in riverine forests-areas of potential contact with Cape genets-compared to areas without Cape genets. Overall, our study underscores the critical role of seasonal environmental changes and interspecific interactions in shaping the activity patterns of two carnivore species within a semi-arid Albany Thicket landscape.

Carnivore space use behaviors reveal variation in responses to human land modification

BACKGROUND

Spatial behavior, including home-ranging behaviors, habitat selection, and movement, can be extremely informative in estimating how animals respond to landscape heterogeneity. Responses in these spatial behaviors to features such as human land modification and resources can highlight a species' spatial strategy to maximize fitness and minimize mortality. These strategies can vary on spatial, temporal, and individual scales, and the combination of behaviors on these scales can lead to very different strategies among species.

METHODS

Harnessing the variation present at these scales, we characterized how species may respond to stimuli in their environments ranging from broad- to fine-scale spatial responses to human modification in their environment. Using 15 bobcat-years and 31 coyote-years of GPS data from individuals inhabiting a landscape encompassing a range of human land modification, we evaluated the complexity of both species' responses to human modification on the landscape through their home range size, habitat selection, and functional response behaviors, accounting for annual, seasonal, and diel variation.

RESULTS

Bobcats and coyotes used different strategies in response to human modification in their home ranges, with bobcats broadly expanding their home range with increases in human modification and displaying temporal consistency in functional response in habitat selection across both season and time of day. Meanwhile, coyotes did not expand their home ranges with increased human modification, but instead demonstrated fine-scale responses to human modification with habitat selection strategies that sometimes varied by time of day and season, paired with functional responses in selection behaviors.

CONCLUSIONS

These differences in response to habitat, resources, and human modification between the two species highlighted the variation in spatial behaviors animals can use to exist in anthropogenic environments. Categorizing animal spatial behavior based on these spatiotemporal responses and individual variation can help in predicting how a species will respond to future change based on their current spatial behavior.

Collaborative behaviour and coalitions in male jaguars (Panthera onca)—evidence and comparison with other felids

Abstract

Most large felids are classified as solitary species, with only lions (Panthera leo) and cheetahs (Acinonyx jubatus) exhibiting social, collaborative behaviours. Herein, we present evidence of the formation of male coalitions by jaguars (Panthera onca), based on data from five studies conducted with camera trapping, GPS telemetry, and direct observations in the Venezuelan Llanos and Brazilian Pantanal. Out of 7062 male records obtained with camera traps or visual observations, we detected 105 cases of male-male interactions, of which we classified 18 as aggression, nine as tolerance, 70 as cooperation/coalition, and eight as unidentified. In two studies, two male jaguars formed stable coalitions lasting over 7 years each. In the Llanos, each coalition male paired and mated with several females. For male jaguar coalitions, we documented similar behaviours as recorded earlier in lions or cheetahs, which included patrolling and marking territory together, invading territories of other males, collaborative chasing and killing other jaguars, and sharing prey. However, different from lions or cheetahs, associated male jaguars spent less time together, did not cooperate with females, and did not hunt cooperatively together. Our analysis of literature suggested that male jaguar coalitions were more likely to form when females had small home range size, a proxy of females’ concentration, while in lions, the male group size was directly correlated with the female group size. Similarly, locally concentrated access to females may drive formation of male coalitions in cheetahs. We conclude that high biomass and aggregation of prey are likely drivers of sociality in felids.

Significance statement

The division into social and solitary species in large felids has so far seemed unambiguous, with only lions and cheetahs classified as social species, in which male coalitions also occurred. Our data show that, under certain conditions, male coalitions may also form in jaguar populations. Factors that drive formation of male coalitions in lions and cheetahs, but not in other species of large cats, have not been clear until now. Our analyses indicate that in jaguars, lions, and cheetahs, the concentration of females likely plays the most important role. In jaguars, the probability of male coalition occurrence is highest in populations with the smallest mean female home range size (and thus likely high local density of females), while in lions, male group size is most strongly correlated with female group size.