We have an ACD/blue heeler - she is 14 - these dogs were bread specifically for herding in the outback of australia - they are not ideal for retreiving but they are very good for flushing out game and herding it towards you - a natural instinct to them is like the Dingo - scavenger so that is why they arent the best for retreiving - a dead bird to them is food
they are however very tempermental and territorial to their owner so training is easy and very natural for them to want to please you