I have 2 Pyrs's and neither one of them will even go near the water. As a matter of fact if it rains outside they will hold there bathroom breaks for as long as possible so they do not get there feet wet.
In the case of my GP, he does not like to swim. They are not a breed that naturally like the water, but they don't necessarily fear it either.
Although Pyrenees aren't really built for swimming, (e.g. no webbed paws) it can be a very individual thing. Marshmellow (now past) enjoyed the water from the time she was a puppy until her last day @ at 12-1/2. Like most things Pyr, it just has to be something they have a reason to want to do - Meli grew up with a Chocolate Lab (Coco)...
Neither my older rescue Ishka, who enjoyes the rain but avoids water, or my younger rescue D'Artagnan who just doesn't seem to care about water, have little desire to swim.
My GP border collie mix loves water and we shaved him last summer due to the heat. He is very much a lover of water and this year we will probably not shave him but put a kiddie pool in our back yard. My in laws have a pond and Remmington, our GP border collie mix, took a fly and leap into the pond and would not come out until he was ready to, just like the breed entails he is very stubborn but very loving to my family
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