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Flay, K. J.

Publications and source records attributed to Flay, K. J..

7 recordsLinked to original sources

Personality and dominance shape core area use and territory-related signalling in a feral ungulate

Space use strategies determine how animals acquire resources and encounter competitors, which ultimately influence their survival. Instead of utilising their entire range uniformly, animals typically concentrate activity in locations where resources are most valuable, and these 'core areas' provide key insights into the behavioural strategies underlying space use. Although competitive ability is often expected to influence core area use, substantial individual-level variation remains unexplained. Consistent behavioural differences among individuals, or personality, may contribute to this variation, but their role in shaping spatial behaviour under natural conditions is poorly understood. To address this gap, we observed adult males (n=24) from a free-ranging, semi-urban population of Asian water buffalo (Bubalus bubalis). We quantified individual core area size and territory-related signalling behaviour, and assessed personality from >9,300 minutes of observations. Most males (79%) shared overlapping core areas with one to five other males but with clear dominance relationships. Social engagement, reflecting a social personality, was positively associated with core area size in subordinates, but not in dominant males. Social engagement was also positively associated with territory-related signalling frequency. By contrast, a non-social personality labelled as activity-maintenance did not influence with core area size or signalling behaviour. We also found that dominant males exhibited lower signalling frequencies than subordinates. Overall, we show that personality and dominance are associated with distinct aspects of spatial behaviour. These findings demonstrate that individual spatial strategies emerge from the interplay between behavioural phenotypes and social lives, highlighting the spatial-social interface as a source of variation in animal space use.

animal behavior and cognition↗

Drivers of space use in a large semi-urban feral ungulate under seasonally fluctuating resource conditions

Resource scarcity prompts animals to adjust their space use in ways that enhance their survival. In wild herbivores, seasonal habitat shifts are well studied; however, little is known about how large herbivores navigate human-dominated landscapes under fluctuating resource conditions. In Hong Kong, feral water buffalo (Bubalus bubalis; henceforth buffalo) experience declines in body condition score during the dry season. While buffalo expand spatial ranges in the dry season, whether this expansion reflects access to improved ecological conditions, and how key anthropogenic factors (like distance to roads and human density) further influence space use, remains understudied. We observed six buffalo herds (n=92 known individuals) across one wet (July-September 2023) and one dry (January-March 2024) season. We recorded herd locations and extracted remotely sensed habitat and environmental data. We used Normalized Difference Vegetation Index (NDVI) as a proxy of vegetation productivity and included elevation, distance to roads, and human density as additional predictors. We hypothesized that dry-season space use would shift toward higher vegetation productivity, and that anthropogenic factors would have weak influence on space use due to the adaption of buffalo in human-dominated landscapes. We found that buffalo used areas with higher vegetation productivity and higher elevation in the dry season than in the wet. Distance to roads and human density had no detectable effect. Our findings reveal that space use by a large herbivore like buffalo in human-dominated landscapes is strategic and resource driven, and that these seasonal shifts may have important implications for local biodiversity and human-animal interactions.

zoology↗

Spatial proximity and dyadic social relationships affect ungulate behavioral synchrony

Collective group decisions are important for the survival and reproduction of social mammals, with inter-individual interactions often driving group-level emergent behavior. Activity synchronization is an important collective behavior, with differences in nutritional requirements leading to foraging asynchrony. Individual variation between animals (such as sex or social relationships) are predicted to affect ungulate synchronization and spatial proximity, with between-sex differences consequently influencing sexual segregation evolution in ungulates. Although investigated independently, the relative roles of sex, sociality and proximity in synchronization are rarely investigated concurrently, especially in regards to affiliative relationships. Asynchrony influences fission-fusion dynamics and social segregation, but little is known how short-term changes in synchrony affects fission. Using a mixed-sex group of feral cattle (Bos taurus), we evaluated the supporting evidence for several predictions arising from the current understanding of synchronization in ungulates. We investigated if sex and social relationships (dominance and affiliation) affected foraging, behavioral synchrony and proximity. We also investigated whether group synchrony affected short-term changes in group size (fission events). We found that same-sex dyads were more likely to be synchronized than mixed-sex dyads, but differences in dominance and affiliation did not affect dyadic synchrony. Focal animals were more synchronized with closest neighbors than with another randomly selected conspecific. Reduction in group size was more likely when group synchrony was lower, highlighting the importance of asynchrony in temporary movement decisions. Inter-individual differences can explain variation in collective behavior, with synchronization being biased towards certain individuals by favoring animals in close spatial proximity and those of the same-sex. LAY SUMMARYIn ungulates, differences in energetic requirements lead to variation in activity, resulting in social and sexual segregation. However, sex, social relationships and spatial proximity are rarely investigated concurrently in relation to synchrony. We investigated synchronization and fission in a feral ungulate relative to individual differences in social relationship and proximity. Sex and proximity affected synchrony and fission events were more likely when synchrony was lower, highlighting the underlying processes in the evolution of sexual segregation.

zoology↗

Adaptive behavioural strategies to seasonal challenges by a semi-urban feral ungulate

Seasonality, or temporal shifts between wet and dry seasons, profoundly affects the behavioural ecology of animals, particularly large herbivores, in (sub-) tropical climatic conditions. Behavioural strategies are crucial for overcoming challenges associated with seasonality. Group-level strategies to seasonality in the wild have received considerable attention, yet little is known about how large herbivores in human-dominated landscapes respond to seasonal challenges. Moreover, focusing solely on groups can obscure how individual animals of different sexes, ages, and personalities respond. We investigated a semi-urban feral population of a large ungulate, the water buffalo (Bubalus bubalis) (N=71) during a wet and a dry season. Individual body condition was non-invasively assessed to evaluate whether seasonality impacts physiology. To identify behavioural strategies, we collected data on feeding (grazing and browsing) and space use (core area and home range). Further, using a subset (n=30), we investigated the associations between personality and space use in the dry season. Body condition scores were highest during the wet season and then declined during the dry season, indicating an impact of seasonality on physiology. Older individuals were more affected than younger ones. Browsing increased during the dry compared to the wet season. While there was no change in core area use, home ranges expanded in the dry compared to the wet season. Regardless of season, females utilised home ranges larger than males. Females exhibiting higher social tension personalities had smaller core areas and home ranges than those with lower social tension. We show that buffalo employ behavioural strategies to overcome challenges associated with seasonality, and these strategies are contingent on intrinsic factors: sex, age, and personality. Our findings offer insights into the ecological principles -habitat use, resource utilisation, and competition- that govern the behavioural ecology of herbivores, and have implications for conservation and welfare in increasingly human-dominated and climate-sensitive landscapes.

zoology↗

Sexual dimorphism and phenotypic plasticity in a subtropical feral bovid Bos taurus (Artiodactyla: Bovidae).

Phenotypes reflect how organisms adapt to their environments. Hong Kong (HK) feral cattle, a crossbreed of Bos taurus taurus and Bos taurus indicus, present an opportunity to study these adaptations in one of the very few global cattle populations not directly controlled by humans. These cattle are free-ranging since their release from farms in the 1970s. HK has a subtropical climate, characterized by high humidity and temperatures during the wet season, and scarce precipitation during the dry season. We studied seasonal coat colour changes in HK feral cattle, and sexual dimorphism in body size and horn length. We provide the first evidence of seasonal changes in coat colour in cattle, with paler coats being more common in the wet season, while darker coats prevailed in the dry season. These seasonal changes were influenced by temperature, humidity, solar radiation, and body condition. We found that males were larger and had longer horns than females. Our results show a male-biased sex dimorphism in the HK feral cattle. Additionally, our findings suggest that thermoregulation costs drive colouration in these cattle. The phenotypic plasticity we demonstrate in these subtropical feral cattle improves our knowledge of the adaptations of ungulates to their habitat.

zoology↗

Personality homophily drives female friendships in a feral ungulate

Friendships, exhibited by both humans and non-human animals, have considerable adaptive benefits. In humans, similarity or homophily in personality is considered a proximate mechanism driving friendships, yet little is known about the behavioural decision rules underlying animal friendships. Some empirical research suggests that animal friendships can be driven by personality homophily. However, these studies are restricted to non-human primates, limiting our understanding of the mechanisms of friendships. We investigated a feral population of water buffalo (Bubalus bubalis) to determine whether homophily in personality drives friendships in this non-model social species in free-ranging environmental conditions. We conducted observations on females (n=30) and assessed their friendships and personalities. Close spatial proximity served as a behavioural indicator of friendship, validated by affiliative body contact. An objective bottom-up method revealed three personality traits - social tension, vigilance, and general dominance. We found that females with comparatively lower personality differences in social tension and general dominance traits exhibited significantly higher close spatial associations. We did not find an effect of kinship on close spatial associations. Our findings show that friendships in buffalo can form based on personality homophily, a decision rule attributed predominantly to primates. We discuss these findings in light of buffalo socioecology but emphasise their implications in the broader evolutionary context of animal personalities and friendships.

animal behavior and cognition↗

Sex and dominance status affect allogrooming in free-ranging feral cattle

Social interactions are fundamental properties of gregarious species, helping to establish dominance hierarchies and maintain social bonds within groups, thus having significant effects on fitness. Cattle (Bos taurus) are social ungulates which engage in affiliative and agonistic relationships with other individuals. Although there are approximately 1.5 billion cattle on the planet, the opportunity to research cattle behaviour in free-ranging groups is rare, as there are few feral populations worldwide. Cattle engage in positive social behaviours such as allogrooming, where one individual licks the body of another. The relationship between affiliative behaviours and other individual characteristics (such as sex and dominance status) are frequently studied in other gregarious species, but are largely undetermined in cattle. To investigate the relationships between sex, dominance status and allogrooming, we observed a mixed-sex feral cattle herd in Hong Kong, recording dominance interactions and allogrooming events. We found that dominant females received more allogrooming than subordinate females, but subordinate females did not perform more than dominant ones. Males performed allogrooming more towards females than other males, but females groomed both sexes equally. Sex affected dominance position, with males obtaining higher status than females, but not all females were subordinate to males. These preferential allogrooming patterns improve our knowledge of sex-specific interactions, and help us to understand the dynamics of agonistic and affiliative behaviours in multi-male, multi-female ungulate groups. Studying a free-ranging feral population provides us with a unique insight into ungulate behavioural patterns and the evolution of cattle social behaviours.

animal behavior and cognition↗