Wildlife management factors and their effects on hair cortisol levels and glucocorticoid and mineralocorticoid levels in the hippocampus of fallow deer (Dama dama) as chronic stress and welfare indicators
Summary
A positive state of welfare for all animals including wild animals is becoming a more
important field of interest for people. Welfare can be seen as a dynamic concept.
According to this concept an animal has to be able to adapt itself to its surrounding
and reach a state that it perceives as positive in order to be in a positive welfare
state. Finding an adequate way to measure welfare in animals can be helpful in
discussions concerning the human role in wildlife welfare. An adequate way to
measure welfare might be by measuring chronic stress indicators. In this study we
measured chronic stress in fallow deer by measuring hair cortisol levels and
glucocorticoid receptor and mineralocorticoid receptor levels in the hippocampus.
These results were combined with information on park management factors to
determine which park management factors contributed to chronic stress and
therefore impaired welfare. Fallow deer from eleven different parks in the UK and
from the Amsterdamse Waterleidingduinen in the Netherlands have been used in
this study. Population density has been identified as an important factor with an
effect on chronic stress in fallow deer. These findings are more pronounced
considering hair cortisol levels than glucocorticoid receptor levels. Based on these
findings we may carefully suggest that management factors in nature parks should
consider population density to reduce chronic stress and thereby improving the
welfare status of fallow deer.