Age determination in jackals (Canis adustus Sundevall, 1846, and Canis mesomelas Schreber, 1778; Carnivora: Canidae) with reference to the age structure and breeding patterns of jackal populations in Zimbabwe

Abstract

Methods for determining the age of individual jackals using canine teeth were assessed as part of a study of the population structure of jackal species (side striped jackal, Canis adustus, and black backed jackal, Canis mesomelas), the main wildlife species maintaining rabies in Zimbabwe. Specimens of both species of jackal were obtained from rabies submissions and culling operations, although the major part of the study involved C. adustus. A method of ageing based on relative pulp cavity width of canine teeth differentiated young adults (one year old) from mature adults, but was of no value in determining the age after one year. A method based on cementum incremental growth layers was of no value as the layers were irregular and did not correspond with pulp cavity width. Canis adustus will breed in their first year but no evidence was found to show that C. mesomelas will normally breed at this age. Up to 60 % of C. adustus were young of year jackals, indicating high population turn over and the potential for rapid population recovery following population crashes.

Key words: canine teeth, pulp cavity, population structure, rabies.