Activity timing of southern water vole (Arvicola sapidus Miller, 1908) in a Mediterranean river

  • December 1, 2015
  • by Isabel Mate, Joan Barrull, Joaquim Gosàlbez, Jordi Ruiz-Olmo & Miquel Salicrú

Knowledge of the alternation between activity and rest during the 24 h daily cycle is important in order to understand how species interact with the environment and can also provide tools for designing appropriate conservation measures. At present, little is known about this alternation in Arvicola sapidus, an endemic rodent restricted to the Iberian Peninsula and France. This study aims to extend our knowledge of this rodent’s hour to hour activity/rest patterns by using radiotelemetry to quantify the distances travelled (associated with activity) by individual southern water voles along a stretch of the Montsant River. The results showed that the southern water vole’s behaviour is cathemeral. The use of data of frequency of activity in one-hour intervals to assess the activity pattern showed a lower resolution than the use of data of the mean distances travelled in one-hour intervals. The individuals occupying a suboptimal habitat travelled a greater mean distance per hour than individuals occupying an optimal habitat, indicating that their activity was related to the habitat conditions. These considerations may help to explain why fragmentation and habitat destruction are emerging as the main cause of the decline of the southern water vole, and underline the importance of habitat conservation to encourage the maintenance of the species.