Supervisors: Dr Domhnall Jennings, Dr Hansjoerg Kunc, Dr Isabella Capellini (Queen's University Belfast)
This project will investigate the extent to which reproductive investment is associated with decline in body condition and over-winter survival in the capital breeding fallow deer.
Capital breeders severely reduce the amount of time they spend foraging when reproductively active, instead relying on stored energy for reproduction and related activities and for subsequent over-winter survival. This project will investigate a number of questions relating to the impact of a capital breeding strategy on the ability of males to invest in the rut, and on their future survival in the fallow deer. Because they limit food intake during this period, the cost of rutting for males can be severe. Prime-aged individuals lose approximately 25% of their body weight over a matter of a few weeks as they compete for access for reproductive opportunities. A key element of this project, therefore, will be to establish whether there is a relationship between day-to-day behaviour (e.g. territory acquisition and defence, aggression, mating success, resting) and decline in body condition of identifiable males during the annual rut.
Mature and immature males should adopt quite different reproductive strategies with young individuals expected to invest in physical growth at the expense of reproduction until they reach prime breeding age. Nevertheless, despite the low probability of mating success some immature males actively participate in the rut by adopting a ‘sneaker’ strategy and consorting with females. The cost of adopting such a strategy in terms of future growth is unknown. A second objective will be to address this question.
The rutting season directly precedes winter with its consequent decline in forage availability and quality. However, we have a very poor understanding of how low-value, scarce winter forage affects survival, maintenance, and energy restocking by individuals in preparation for high cost outputs such as antler growth and the subsequent rut. This project will investigate the links between behaviour, body condition and weight gain and the probability of over-winter survival.
The accurate measurement of weight loss in free-ranging populations is rare because measuring body size in the field is usually not practical, or ethically permissible. Recent developments in laser digital-photogrammetry to measure body size in wild animals offers a resolution to this problem. Using this technology, the student will study the rutting behaviour and effort of individually identifiable male fallow deer resident at Phoenix Park (Dublin, Ireland) to address the objectives outlined above.
Start Date: 1 October 2022
Duration: 3 years