A study has shown that the current guidelines for stalkers stating that calves should be shot with their mothers, are correct. The study was the result of scientists from the Universities of Calgary, Edinburgh and Cambridge looking at 40 years? worth of data collected on the Isle of Rum. The team found that when a calf aged between seven and 13 months lost its mother, it struggled to find food and shelter, and that the effects were more extreme on female calves than males. Male deer orphaned after they reached two years old were more likely to survive, while with female calves the chances of survival with no mother were lower whatever their age when orphaned. This can be explained by the fact that young stags leave their mothers at around two years old, while females remain with their ?kin? groups, where the mother would offer protection.