Department of Physics, Chemistry and Biology (IFM)

In this study, all parks in Sweden that keep European bison were included. Since there were only seven such parks and few animals in each of them, the number of data samples was small which may have affected the results. Other studies have had similar difficulties to obtain statistically significant results due to small sample size (Boissy 1995). Studies have also shown that, under the same conditions, there is individual variability in many aspects of behaviour (Boissy 1995).

The European bison observed in this study did not show stronger reaction to stimuli from the two predators than to the herbivore control in any of the tests, so their interest in the different stimuli might just be of curiosity, not increased vigilance to avoid predation. Many species need to learn to recognize their predator in order to perform proper anti-predator behaviour (Blumstein et al., 2002; Blumstein 2006).

The results gave some support to the hypotheses in this study. The European bison kept in enclosure with different characteristics did respond differently to the same stimulus which supports the first hypothesis. These results are consistent with the results from other studies. Håkansson and Jensen (2005) found in their study on red junglefowl, Gallus gallus, behavioural differences between different captive populations. If these differences were due to adaptation to the different types of enclosures or genetic changes was not clear. Since all European bison are closely related, it is difficult to say if the differences found in this study are en effect of the enclosures the animals were kept in or just due to individual differences. The European bison responded stronger to the visual stimulus than to the auditory stimuli which give some support to the second hypothesis, but no difference between stimuli from different animals was found. The European bison changed their behaviour after the stimuli presentations compared to the pre-test baseline, which supports the third hypothesis.

The results from this study show that enclosure characteristics might have an effect on the anti-predator behaviour in the European bison. However, the differences could also be due to individual differences. Considering the limited number of animals and parks observed in this study and many factors that might have had an affect on the results, makes it difficult to decide whether some of these animals are more or less suitable to be released into the wild. These results should be supplemented with more studies on the behaviours of the European bison in which more animals are included in order to make any proper conclusion of how this species should be kept in the future.