They may not have the red swimsuits or the zinc oxide on their noses, but some dogs are such proficient swimmers that they can serve as lifeguards! Of course, there are some requirements because the likelihood of an aquatically-advanced Chihuahua being able to save a 200lb man, is absolutely absurd. It’s true, though, that some dog breeds have become excellent lifesavers; namely Newfoundlands, Portuguese Water Dogs and Labrador Retrievers.
While all three are consistently strong swimmers, Newfies have been seen in this capacity more-so than the others; likely because of their size and ability to support larger humans. Their thick coats insulate them from colder temperatures, while their webbed paws propel them through the water and their powerful tails act as a rudder.