| Interactions between pairs of red-backed voles were
observed in a neutral observation arena in the summer of 1975 at Heart Lake, Northwest
Territories, Canada. Twenty-one behaviours were recorded for each vole and were simplified
to six factors of behaviour: amicable, defensive, aggressive, avoidance, subordinate, and
fighting. The behaviour of one vole towards another in a trial was classified into
defensive, avoidance, amicable, and aggressive types by unweighted pair group method
(UPGM) cluster analysis. It was possible to partially predict behaviour on the basis of
individual parameters such as: sex, age, and reproductive condition. The relationship
between individuals showed better predictability, although the behaviour of each
individual was variable. Male-female encounters were generally amicable with the female
being dominant. Female-female encounters were similar to male-male encounters; avoidance,
defensive and aggressive behaviour predominated. Dominant females were generally older or
in a later stage of pregnancy. Dominant males did not represent any consistent trends in
age, sexual maturity, or weight differences. Mutual avoidance was the most common type of
interaction. |