There are no natural predators of deer in Britain. Therefore, to maintain a stable and healthy population of deer a cull of some of them is required each year. This is not random however, and a deer stalker will have carried out a population count/census to determine the age and sex profile of those to be culled. So then during the correct deer season, barren, genetically odd or very old animals are taken. This selection results in a balanced pyramid profile with a few healthy older animals of each sex at the top and with increasing numbers of each sex down to the yearlings at the bottom.