A multi‐property assessment of intensity of use provides a functional understanding of animal movement

Abstract

Abstract The intensity of use of a location is one of the most studied properties of animal movement, yet movement analyses generally focus on the overall use of a location without much consideration of how patterns in intensity of use emerge. Extracting properties related to intensity of use, such as the number of visits, the average and variation in time spent and the average and variation in time between visits, could help provide a more mechanistic understanding of how animals use landscape. Combining and synthesizing these properties into a single spatial representation could inform the role that a location plays for an animal. We developed an R package named ‘UseScape’ that allows the extraction of these metrics and then clustered them using mixture modelling to create a spatial representation of the type of use an animal makes of the landscape. We illustrate applications of the approach using datasets of animal movement from four taxa and highlight species‐specific and cross‐species insights. Our framework highlights properties that functionally differ in how animals use them, contrasting, for example, heavily used locations that emerge because they are frequented for long durations, locations that are repeatedly and regularly visited for shorter durations of time or locations visited irregularly. We found that species generally had similar types of use, such as typical low, mid and high use, but there were also species‐specific clusters that would have been ignored when only focusing on the overall intensity of use. Our multi‐system comparison highlighted how the framework provided novel insights that would not have been directly obtainable by currently available approaches. By making the framework available as an R package, these analyses can be easily applicable to a myriad of systems where relocation data are available. Movement ecology as a field can strongly benefit from approaches that not just describe patterns in space use, but also highlight the behavioural mechanisms leading to these emerging patterns.

Keywords

• animal movement
• clustering
• GPS telemetry
• intensity of use
• mixture model
• recursive movement