Résumé
In this work, we documented the influence of earthworm's galleries on their speed of movements during dispersal events in the soil. We quantified, by using X-rays, the dispersal behaviour of earthworms in the soil. The observations were conducted in mesocosms in controlled conditions for 12 h. Our experiments revealed that during a dispersal sequence of a batch of individuals of the species Aporrectodea terrestris (Savigny 1826): (a) individuals used preferentially existing conspecifics' galleries, (b) individual velocity increased after each dispersal event and (c) the lag time before each dispersal event did not seem to be influenced by previous dispersers. Therefore, dispersal seems to be facilitated by conspecifics' activity, which strongly supports the hypothesis of a feedback between ecosystem engineers' activity and their dispersal speed