Water dogs are usually medium sized, active dogs, their most distinctive feature are their tight waterproof coats and their strong desire to swim. Traditionally many long haired water dogs breeds have their coats clipped with a bare midriff and hindquarters to assist in swimming by reducing drag, whilst retaining a long coat around their torso to prevent thermal shock when jumping into freezing water. This classic clip is seen to this day in dog shows with some breeds such as Poodles retaining a variation of this clip. Source: https://en.wikipedia.org/