Applied methods for studying animal behaviours in the wild: Alpine Marmot [Marmota marmota] as a case of study.

Résumé

Behavioural displays have been investigated for a long time. From the beginning of ethological studies till nowadays several techniques have been applied over and over again to different species. Different resource distribution can occur within alpine meadows inducing individual behavioural adjustments in use of territory that is one of the most important aspects of the life history of many animals but in particular of our study object: Alpine marmots (Marmota marmota). We propose a new method to collect spatial data using a tested device showing a very low intra-inter observers variability (P < 0.001) and a very good accuracy compared to GPS: all points we obtained were inside the 95% CI of 20 repetitions we got for each tested point. We applied scan sampling methodology to estimate home-range size of 44 marked marmots, using the proposed instrument, that were repeatedly weighted during the summer thanks to electronic scales placed in front of the burrow entrances. Studying two Alpine marmot groups belonging to the same population in two zones located at different altitudes we found marmots living at lower altitude had larger home-ranges and lower daily mass gain than marmots living at higher altitude. This pattern was related to differences in resource distribution of the two zones; plants availability of the high zone was constantly higher than that one of the low zone.