fission-fusion dynamics in sheep: the influence of resource distribution and temporal activity patterns

Fission-fusion events, i.e. changes to the size and composition of animal social groups, are a mechanism to adjust the social environment in response to short-term changes in the cost-benefit ratio of group living. Furthermore, the time and location of fission-fusion events provide insight into the underlying drivers of these dynamics. Here, we describe a method for identifying group membership over time and for extracting fission-fusion events from animal tracking data. We applied this method to high-resolution GPS data of free-ranging sheep (Ovis aries). Group size was highest during times when sheep typically rest (mid-day and at night), and when anti-predator benefits of grouping are high while costs of competition are low. Consistent with this, fission and fusion frequencies were highest during early morning and late evening, suggesting that social restructuring occurs during periods of high activity. However, fission and fusion events were not more frequent near food patches and w..., The study was conducted at Fowler's Gap Arid Zone Research Station in Australia, in 2018. Our study tracked a herd of 50 female merino sheep (Ovis aries) interacting in a paddock over 16 days. The paddock did not include any other conspecifics, and was approximately 6 km2 in size. It contained one water trough and 10 food locations consisting of bales of hay. The region was severely affected by drought and most of the annual vegetation that sheep would graze on was absent. Thus, the provided hay constituted the vast majority of food resources available to the study animals. We recorded the locations of all 50 sheep every 6 seconds for 24 hours each day using GPS collars. Every four days, sheep were captured to change GPS collar batteries. The data from these capture time periods were excluded from the analysis. Sheep were undisturbed during the 4-day tracking periods (86 to 88h each). GPS collars (GPS, i-gotU GT-120 by MobileAction, with a larger battery CE04381 by Core Electronics) wei..., All files have been uploaded as csv files which can be opened by a variety of open-source and proprietary resources., # Fission-fusion dynamics in sheep: the influence of resource distribution and temporal activity patterns

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The uploaded data contains fission-fusion event analysis for several different combinations of radii. Whenever not specified, the data uses the radii 30m and 50m as in the manuscript's main text.

Ts contains the conversion from the time step in the first column to Unix time in the second column. The time step is the number of data collection points (6s intervals) since the start of data collection.

PaddockCornersFoodWater contains the coordinates of paddock corners, feeding, and water locations, again as coordinates in the WGS 84 / UTM zone 54S projection. (A previous version of this file was named Salt6\_corners\_food\_locations\_collective\_decision\_making\_March2019.csv)

GroupsPerTime contains the groups with a row for each time step (see Ts) and each group consists of a list of sheep ID numbers separated by commas.

AllCoordinates files contain the centroid/average coo...