Post-weaning dispersal behaviour of male fallow deer fawns: Investigation the role of behaviour, growth and stress

Male and female fallow deer inhabit different territories, except for the October rut where males move to the female range. From birth in June fawns go through several life-critical stages; initially they adopt a hider strategy, live away from the main herd and are fully dependent on the mother for nutrition. In July, mothers gradually begin to bring their fawns into the doe herd where males remain until aged between eight and ten months when some individuals disperse and can be observed associating with the bucks in the male territories. Investigating why some juvenile male fawns move from their maternal groups and establish themselves in the all-male (bachelor) group, whilst other stay longer with their maternal group, or fail to leave at all. What are the reasons underlying the disparity in these choices, and what, if any, are the fitness consequences for this difference in strategy? Do males that disperse invest in more in growth prior to dispersal, do they have more connected social networks, are they are less stressed or more aggressive than males that remain? This project will explore the links between behaviour, investment in growth and hormones (cortisol and testosterone) in relation to the fawn's decision whether, and when to time its dispersal from the doe herd to take up residence in the bachelor herd.