The Labrador Retriever is the most popular Dog in the United States. It is also one of the most popular assistance breeds. Labradors come in three bold colors – Black, Yellow and Brown, where black is the most common and chocolate is the rarest. The Labs have webbed Paws which makes them one of the strongest k9 swimmers. They have an otter-like tail which acts like a rudder in the water and a layered slightly oily coat that keeps them warm and keeps water off like oil.