Larks absolutely love the water. We are working on retrieving in the water and I swear she would do it until she passed out! I usually make her stop after a few retrieves because I get nervous about her getting too tired. Do your dogs wear a life jacket? If so what kind? She is a great swimmer and I keep her fairly close to shore so I could rescue her if needed but I know she will want to adventure farther as she gets older.
My girl absolutely adores waters retrieves as well but I restrict to around 6 or so at a time of different distances. As a keen and confident swimmer she has never worn a life jacket even for her first expeditions in the local lake at around 3.5 months of age. I would't worry as long as Larks is confident and you keep the distances sensible and keep the retrieves down to 5 or 6 max at a time. My girl isn't at all interested in 'swimming' and without a retrieve on offer will only splash around in the water, not swim
First of all, swimming is harder on dogs than many think. Yes, it's non weight bearing. But think of how fast you yourself can run in water as compared to on land. Much slower, right? Same for dogs, water is more dense than air. Too much swimming without building up, same as any exercise, can strain ligaments, joints, tendons, heart, lungs. You are right to limit her after just a few retrieves, plus doing just a few keeps her keen. Work on recall so you can control her adventuring even when she is swimming. I never put a life jacket on when we were canoeing and certainly not for swimming but for a bigger boat they are handy for hooking a pole into the back to help lift the dog back up on to the boat. For canoeing, when we tripped it would be hours in the canoe and we worried lifejackets were too hot. We wore ours though our dogs were well trained/behaved and we did not go far from shore.
An interesting question and answers! It's actually one of the things I've wondered about with looking for a Lab puppy. I've never had a dog who could swim and my last dog, Brogan, loved water but was maniacally careful about not going in past his knees. I would watch dogs (mainly Labs and Lab mixes) dive into heavy surf in California and was grateful I didn't have to worry about Brogan wanting to do that because it looked dangerous to me. I think I'll be more than a bit nervous if I get a Lab who likes to swim too far out and probably will feel the same way as you about wanting to slap a life jacket on him!
We live near the tidal Thames where the currents can be very strong. Homers walks are along the river bank. He'll jump in for a splash and will paddle about up to his belly if the water is low or jump in and swim near the bank when the tide is high. He lives to go after his ball in the water but we only throw it out no more than 3 meters or so as the current is a lot stronger near the middle of the river. We've learnt a few lessons one of which is to only throw a tennis ball that he can pick up easily rather than his rugby ball which he can't get as good a grip on and ended up pushing it further into the river as he was pulled further downstream by the current.
Labs were originally bred to retrieve fishing nets and fallen sailors over the Grand Banks of Newfoundland if I'm not mistaken. They need to get built up to a certain fitness level, they can't just jump in and swim. I also hunt ducks with dogs and there's a concearn with them getting caught up in reeds and trees etc so we never use lifejackets. Strong currents is another story. We take particular caution with currents. Except for the few really smart ones out there they will swim into the current back to you instead of cross current to shore and then run back up land. Like already mentioned. It's your job to recognize that Larks is getting tired and end the games. I know also of a type of neoprene lifejacket that people use that can actually overheat your dog on hot summer day and cause health issues.
