Jeffrey Driscoll

Concordia University
M.Sc. candidate

Supervisor: Robert Weladji
Start: 2016-09-01
End: 2018-08-01


The relationship between operational sex ratio (OSR) and the intensity of competition in reindeer (Rangifer tarandus L.): the effect of male age
The aim of this MSc is to study the impact of a manipulated OSR on the competition intensity of reindeer (Rangifer tarandus tarandus) during their rut in a semi-natural environment. This project aims to replicate Alo (2016), however, we will utilize 2.5 and 3.5-year-old male reindeer instead of 1.5-year-old males, to investigate if age is an important factor on the behaviours exhibited by reindeer in the presence of either a balanced OSR (3♂:3♀) or a female-biased OSR (3♂:6♀). The main predictions would be: (a) as OSR increases, intrasexual competition between males will increase, whereas female-female aggression will decrease, (b) reproductive effort and mating tactics can be adapted when faced with a heavily biased OSR and (c) utilization of alternative mating tactics will increase with age and thus more experience. The results from this project will increase our understanding of the mating behaviour and reproductive success of reindeer, which can be generalized to caribou (Rangifer tarandus caribou), their North American counterpart. As well, we hope to add this large mammalian species example to the growing body of literature highlighting the influence of OSR on the intensity of sexual selection.


Rangifer tarandus, Operational sex ratio, Animal behaviour, Behavioral Ecology


1- Age determination in crustaceans: a review
Kilada, Raouf, Jeffrey G. Driscoll
2017 Hydrobiologia