Nest site fidelity in the Slovakian population of the European pond turtle Emys orbicularis

In many places in Europe, the pond turtle Emys orbicularis (Linnaeus, 1758) is an endangered species. Establishing its reproductive pattern is critical for the understanding and protection of this turtle. In this study, which took place from 1998 to 2009 in the Tajba National Nature Reserve, Slovakia (48°23′N, 21°47′E), are presented the results concerning the spatial and temporal aspects of nesting habits of individual turtles. From the total monitored group of 39 turtles, eight individuals which laid eggs more than four times during the whole study period were selected for statistical evaluation. It was found that five individuals from this group demonstrated a fidelity to the nesting area, and that the egg-laying period starts in mid-May and continues until late June. During the investigation, six turtles nested twice per year with an interval of about 24 days. The average distance between the nests of an individual turtle was close to 138 metres, and the distance of the nests from water was about 349 metres. The data obtained on the space and time requirements of the European pond turtle for successful reproduction are helpful to protect this species more efficiently, not only in the Tajba National Natural Reserve, but also in other similar sites in Europe.