Spatial strategies in non-territorial societies: How feral horses maintain boundaries with other groups

Encounters between competitive individuals or groups are common in social animals and can involve costly aggression; thus, animals often employ strategies to minimise direct conflict. However, research on whether and how animals adjust their group spatial structure when they encounter or spatially co-occur with a different group remains limited. We investigated how non-territorial units in feral horse multilevel societies manage spatial encounters with neighbouring units. We observed 25 reproductive units in northern Portugal, using drones, and employed statistical analyses to quantify spatial dynamics. We found that horses actively adjusted their spatial formations depending on the proximity of other units. Units became more circular and cohesive when other units approached, but when extremely close, they elongated their shapes to avoid boundary crossings. These adjustments indicate that horses maintain flexible unit boundaries to prevent mixing with other units. A notable exception wa..., , # Data from: Spatial strategies in non-territorial societies: How feral horses maintain boundaries with other groups

Dataset DOI: [10.5061/dryad.m905qfvft](https://doi.org/10.5061/dryad.m905qfvft)

## Description of the data and file structure

The positional data of feral horses was acquired in Serra D'Arga, Portugal, in 2017. We used drones to obtain the images of the horses and identified the individuals from the aerial photographs.

### Files and variables

#### File: rawdata_position2017.xlsx

**Description:** the positional data of feral horses

##### Variables

* ID: individual ID

- group: group ID

* age: age class. 'foal' as 0 year old, 'young' as 1-4 years old, adult as 5 years old or older.

- SEX: sex. 'NA' means sex was not identified.

* code: the observation code. 60102 represents 6 = June, 01 = 1st, 02 = 2nd observation of the day.

- zone: whether the individual was observed at zone 1 or zone 2 in the observation site (see Figure 1 in the main manuscript).

* xcoord, ...,