Spatial and temporal dynamics of lekking behaviour revealed by high-resolution GPS tracking

- New tracking technologies enable high spatial and temporal resolution data.
- Territorial males' ranges were overlapped by floating males.
- Within a season less than a third of the males were constantly territorial.
- Males tended to reduce their range with age and to be site faithful.
- Lekking system was found to be dynamic at the inter- and intraseason level.

Even though leks have been widely used by biologists as a model to study sexual selection, we still do not understand how lekking individuals use space, interact and socially progress over time. This study aimed to provide new insights into lekking breeding dynamics using a high temporal and spatial resolution data set derived from the GPS tracking of adult male little bustards, Tetrax tetrax, collected over a 4-year period. We found the lekking system was dynamic at both intra- and interseasonal scales. Smaller ranges were consistent with territorial behaviour. Using Bayesian latent cluster analysis, based on the movements of each individual, we were able to distinguish between breeding behavioural modes, territorial and floating, within the breeding season. Surprisingly, only 27% of the males were found to be constantly territorial within the same year. The remaining birds showed predominantly floating behaviour or shifted between the two behavioural modes, floating and territorial, possibly indicating male turnover. Birds that were tracked for more than 1 year tended to return to the same breeding range. Floating males between years reduced their ranges within the same area and became territorial, indicating a trend for rank progression with increasing adult age. The combination of territorial site fidelity and male rank ascent based on age can explain the temporal persistence of leks within stable habitats.