Effects of the captive environment and enrichment on the daily activity of European Bison (Bison bonasus)

Sammanfattning:

When breeding wild species in captivity, the animals may gradually become more adapted to captivity and therefore less suited for reintroduction which is the ultimate goal for some species. This study measured the activity budget of European bison (Bison bonasus) in six enclosures in Sweden with the aim to find out how the characteristics of the enclosures – with and without pasture - influenced the activity budget. The results show that there were significant differences in the activity budget, i.e. the activity was higher in the enclosures with pasture than in enclosures with barren ground. However, since barren enclosures were smaller than naturalistic, it was not possible to exclude the effect of size. Judged from observations of bison in the wild, there seems to be a direct correlation between food availability and ranging, indicating that enclosure characteristics affect activity more than size. The bison foraged differently in the two enclosure categories, but the total amount of time spent on feeding did not differ. A feeding enrichment experiment showed to have more positive effects in the barren enclosures than in the naturalistic ones, as the amount of time of inactivity decreased in the former. Since the genetic characteristics of all Swedish bison are very similar, the differences between the two enclosure groups indicate that the animals still have the ability to respond appropriately to improved environmental quality. Hence the next step in the assessment of the suitability of these bison for release would be to study them during an acclimatisation program.