Bridging animal personality with space use and resource use in a free-ranging population of an asocial ground squirrel

Studies of aggression and space use are essential to understanding resource use by reptiles, particularly lizards. Research in this area, however, exhibits bias in that the seminal work has been done on (1) species that are highly visible in their habitats (e.g. Iguanians); and (2) males. Studies of secretive species such as skinks and of females are less common. Here, we present results of a lab study of dyadic encounters of adult females of a common North American skink: Scincella lateralis (Little Brown Skink), and compare them to results obtained from an earlier study of adult males of the same species. Female S. lateralis never interacted unless they were within one body length of each other. The most common behavior exhibited was avoidance of one lizard (the subordinate) away from the other lizard (the dominant). As a result, the two lizards spent more time apart than close together and rarely shared the retreat. The larger of the two females was dominant in 9 of 10 trials. Compared to adult males, adult females showed far fewer aggressive behaviors such as lunging or chasing, and never bit each other. Unlike males, however, subordinate female S. lateralis exhibited tail twitching significantly more often than did dominants, suggesting this behavior may be a social signal for females, though the data suggest there may be other possible functions. Despite differences in the frequency of behaviors exhibited, patterns of space use and retreat use were the same in females as they were in males.

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When the going gets tough: behavioural type-dependent space use in the sleepy lizard changes as the season dries

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2015.1768 ◽

2015 ◽

Vol 282 (1819) ◽

pp. 20151768 ◽

Cited By ~ 45

Author(s):

Orr Spiegel ◽

Stephan T. Leu ◽

Andrew Sih ◽

Stephanie S. Godfrey ◽

C. Michael Bull

Keyword(s):

Species Interactions ◽

Space Use ◽

Disease Spread ◽

Gps Tracking ◽

Dependent Manner ◽

Behavioural Type ◽

Animal Populations ◽

Distribution Of Resources ◽

Neighbourhood Scale ◽

Free Ranging

Understanding space use remains a major challenge for animal ecology, with implications for species interactions, disease spread, and conservation. Behavioural type (BT) may shape the space use of individuals within animal populations. Bolder or more aggressive individuals tend to be more exploratory and disperse further. Yet, to date we have limited knowledge on how space use other than dispersal depends on BT. To address this question we studied BT-dependent space-use patterns of sleepy lizards ( Tiliqua rugosa ) in southern Australia. We combined high-resolution global positioning system (GPS) tracking of 72 free-ranging lizards with repeated behavioural assays, and with a survey of the spatial distributions of their food and refuge resources. Bayesian generalized linear mixed models (GLMM) showed that lizards responded to the spatial distribution of resources at the neighbourhood scale and to the intensity of space use by other conspecifics (showing apparent conspecific avoidance). BT (especially aggressiveness) affected space use by lizards and their response to ecological and social factors, in a seasonally dependent manner. Many of these effects and interactions were stronger later in the season when food became scarce and environmental conditions got tougher. For example, refuge and food availability became more important later in the season and unaggressive lizards were more responsive to these predictors. These findings highlight a commonly overlooked source of heterogeneity in animal space use and improve our mechanistic understanding of processes leading to behaviourally driven disease dynamics and social structure.

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Adaptations for hibernation in the depot fats of a ground squirrel (Spermophilus beldingi)

Canadian Journal of Zoology ◽

10.1139/z91-382 ◽

1991 ◽

Vol 69 (11) ◽

pp. 2707-2711 ◽

Cited By ~ 36

Author(s):

Craig L. Frank

Keyword(s):

Fatty Acids ◽

Adipose Tissue ◽

Melting Point ◽

Ground Squirrel ◽

Unsaturated Fatty Acids ◽

Ground Squirrels ◽

Body Temperatures ◽

Melting Points ◽

Spermophilus Beldingi ◽

Free Ranging

Ground squirrels are small herbivores that hibernate during winter. The ecological–nutritional limitations on hibernation are virtually unknown, but one constraint may be the melting point of stored fat. Lipids must be fluid to be metabolizable, and body temperatures maintained during hibernation are usually 30 °C below the melting point of typical mammalian fats. Fats containing greater amounts of unsaturated fatty acids, however, have correspondingly lower melting points. White adipose tissue was sampled from free-ranging Belding's ground squirrels, Spermophilus beldingi, during both the summer and fall. The lipids were twice as unsaturated as those of other rodent species, most of the increased unsaturation being due to the accumulation of plant-produced polyunsaturated fatty acids derived from the animals' diet. The melting points of S. beldingi fats were consequently 25 °C lower than those of other mammals. These results suggest that ground squirrels may depend upon their plant diet for the polyunsaturates necessary to produce the lipids with low melting points that are needed for hibernation.

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Quantifying the influence of space on social group structure

10.1101/2020.12.10.419317 ◽

2020 ◽

Author(s):

Julian Evans ◽

Jonas I. Liechti ◽

Matthew J. Silk ◽

Sebastian Bonhoeffer ◽

Barbara König

Keyword(s):

Social Structure ◽

Empirical Data ◽

Social Preferences ◽

Group Structure ◽

Space Use ◽

Assignment Test ◽

Interaction Patterns ◽

Simple Method ◽

Long Term Study ◽

Free Ranging

AbstractWhen studying social behaviour, it can be important to determine whether the behaviour being recorded is actually driven by the social preferences of individuals. Many studies of animal social networks therefore attempt to disentangle social preferences from spatial preferences or restrictions. As such, there are a large number of techniques with which to test whether results from network analysis can be explained by random interactions, or interactions driven by similarities in space use. Selecting which of these methods to use will require determining to what extent space might influence social structure. Here we present a simple method (Social Spatial Community Assignment Test) to quantify the similarity between social and spatial group structure. We then apply this method to both simulated and empirical data of social interactions to demonstrate that it can successfully tease apart social and spatial explanations for groups. We first show that it can resolve the relative importance of space and social preferences in three simulated datasets in which interaction patterns are driven purely by space use, purely by social preferences or a mixture of the two. We then apply it to empirical data from a long-term study of free-ranging house mice. We find that while social structure is similar to spatial structure, there is still evidence for individuals possessing social preferences, with the importance of these preferences fluctuating between seasons. Our method provides a robust way of assessing the overlap between spatial and social structure, which will be invaluable to researchers when investigating the underlying drivers of social structure in wild populations.

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Habitat and space use of an abundant nearshore shark, Rhizoprionodon taylori

Marine and Freshwater Research ◽

10.1071/mf13272 ◽

2014 ◽

Vol 65 (11) ◽

pp. 959 ◽

Cited By ~ 18

Author(s):

S. E. M. Munroe ◽

C. A. Simpfendorfer ◽

M. R. Heupel

Keyword(s):

Resource Use ◽

Space Use ◽

Activity Space ◽

Benthic Habitat ◽

Habitat Types ◽

Movement Data ◽

Habitat Specialisation ◽

Spatial Management ◽

Passive Acoustic ◽

Conservation And Management

Shark resource-use strategies affect how they will respond to changes within their environment and, as such, may be important to consider in conservation and management. Movement data on sharks that use nearshore areas is particularly valuable because these habitats are highly dynamic. The present study used passive acoustic telemetry to examine the space-use, habitat-selection and habitat-specialisation patterns of the Australian sharpnose shark, Rhizoprionodon taylori, in a nearshore area. Habitat selectivity and specialisation were assessed across five benthic habitat types, including outer bay, seagrass, reef, sandy inshore and intertidal mudflats. The majority of R. taylori sharks were present for short periods of time, ranging from 1 to 112 days (mean ± s.e. = 16.9 ± 4.9). Activity-space analysis indicated that R. taylori roamed widely, but monthly activity-space size was consistent among individuals and through time. Both the population and individuals displayed wide habitat niches, indicating that the species may be resilient to environmental change. However, R. taylori consistently selected for seagrass over other habitats, potentially for feeding. Therefore, declines in seagrass availability may reduce R. taylori presence in nearshore areas and may be relevant to spatial management of this species.

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A quick guide to video-tracking birds

Biology Letters ◽

10.1098/rsbl.2008.0075 ◽

2008 ◽

Vol 4 (4) ◽

pp. 319-322 ◽

Cited By ~ 13

Author(s):

Lucas A Bluff ◽

Christian Rutz

Keyword(s):

Social Interactions ◽

Resource Use ◽

Video Tracking ◽

Movement Trajectory ◽

Field Techniques ◽

Video Footage ◽

Wide Range ◽

Free Ranging ◽

Positional Data ◽

Basic Equipment

Video tracking is a powerful new tool for studying natural undisturbed behaviour in a wide range of birds, mammals and reptiles. Using integrated animal-borne video tags, video footage and positional data are recorded simultaneously from wild free-ranging animals. At the analysis stage, video scenes are linked to radio fixes, yielding an animal's eye view of resource use and social interactions along a known movement trajectory. Here, we provide a brief description of our basic equipment and field techniques to enable other researchers to start their own video-tracking studies.

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Using fine-scale spatial analysis to study behavioural strategies prevalence in wild groups of drift-feeding fish

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2018-0221 ◽

2019 ◽

Vol 76 (10) ◽

pp. 1854-1861

Author(s):

Aurélien Vivancos ◽

Gerry Closs

Keyword(s):

Spatial Analysis ◽

Social Behaviour ◽

Group Living ◽

Space Use ◽

Social Contexts ◽

Social Organisation ◽

Drift Feeding ◽

The Social ◽

Key Aspects ◽

Free Ranging

Key aspects of the social behaviour of groups of drift-feeding fish can be inferred by the way space is shared between group members, because they inhabit a very dynamic and complex environment where spatial positions have a direct impact on fitness-related traits. Therefore, the spatial analysis of such a system can reveal important insights into behavioural ecology of fish, but so far, technical constraints limited this approach to only large salmonids. We used a digital imaging technique to monitor movements and behaviour of free-ranging groups of juvenile galaxiids (Galaxias anomalus) facing two contrasting physical and social contexts. We described the spatial structure of these groups and studied individual space use in relation to their social behaviour. We found that prevalence of territorial behaviour differs greatly between sites, which suggests that groups were displaying different social organisation. This study showed that detailed spatial analysis of space use and behaviour of drift-feeding fish could provide new insights into the social organisation of group-living animals.

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