1. The management of ungulate populations for sport in the presence of potentially conflicting interests such as conservation, either of the animals or of the habitat they use, may be formulated as a problem of optimization subject to constraints.
2. A deterministic simulation model was developed to assess optimal culling strategies for Scottish red deer. The aim was to allow deer population size to be reduced while maintaining a given annual cull of mature males (stags).
3. To achieve the above aim, the model indicated that the female (hind) cull should be restricted to non-lactating adult (yeld) and immature hinds.
4. If, instead, only calf and hind pairs are culled, the population size must be roughly 14% larger to achieve the same cull of mature stags.
5. Under ideal conditions, it seems possible to reduce hind numbers so that there are just two hinds of age ≥ 1 for every stag of age ≥ 6 in the population, provided that the population is maintained well below the maximum sustainable size (carrying capacity). Under this strategy, the model indicated that the ratio of stags of age ≥ 1 to hinds of age ≥ 1 should be between 1.5 and 1.8 to 1.0.
6. In principle, for populations well below carrying capacity, for every 10 mature stags to be stalked annually, it seems possible to reduce numbers such that the summer population comprises just 70 stags, 40 hinds and 20 calves.
7. In practice, limited culling of hind and calf pairs and young stags for quality control or other reasons, together with the need for a margin of safety, dictates that the hind population should be rather larger than this. However, on most estates in Scotland, hinds currently outnumber stags by roughly 2:1, so that our results suggest that large decreases in numbers of hinds can be achieved without incurring a loss of revenue from stalking.
8. If the market expectation were to be changed so that hunters wished to stalk stags regardless of age, rather than just those with perceived 'trophy' value as mature animals, the same number of deer could be stalked at an even lower population density, to the benefit of other land uses.
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