BEHAVIOURAL SIGNIFICANCE OF THE MOOSE BELL

Abstract

It is hypothesized, through observation, that the primary function of the bell of moose (Alces alces) is to disseminate and transfer by contact, the urinary and possibly salivary pheromones of the bull close to or directly on the nose area of the cow. The large surface area and higher amount of sebum of the bell, in comparison with that of the cow, enables retention in the hair of great amounts of pheromones and deceleration of evaporation of those which are bipolar. The cow searches for these pheromones on the tongue, lips and nose area of the bull by: (1) direct contact when the bull urinates; (2) more frequently by rubbing her face all over the bell and adjacent parts of the throat which are impregnated by urinary pheromones from the rut-pit-hole; (3) by rubbing her chin and cheeks in the fresh pithole. By this way her smaller, tail-shaped bell is impregnated and becomes a reservoir of pheromones, swinging close to the nostrils, when the cow is running. Since both sexes produce the same urinary pheromones during estrus, a very effective mutual stimulation of gonadal activity and synchronization of estrus of the cows around the bull is thus achieved. This is considered as a necessary prerequisite for short, successive and economic mating strategy in the tundra, probably the original habitat of the moose.