Contrary to what many people believe, not all dogs are good swimmers. I once had a miniature schnauzer that would sink like a rock when you put him in the pool. Dogs like him must be taught to swim, which isn't always easy. Depending on how frightened your dog is of the water, teaching him to swim may take several weeks. Like anything else, the key to success is patience and persistence.
Tackle the fear first - If your dog is afraid of the water, the first thing you need to do is help him conquer that fear. Start by playing with him in shallow water. If you have a pool, sit with him on the step where he is no more than ankle deep in water. All my dogs love to chase splashes, so splashing in shallow water is a good way to start. Gradually allow him to be in deeper water, but be sure not to rush this step. A dog that is afraid of the water will be panicky and may never learn to swim. If you don't have a pool, you can use a bathtub, but you should get into the tub with him to show him that it is OK.
Be his sidekick - Once he has conquered his fear of water, hold onto him as you slowly cruise around. Dogs instinctively paddle their legs in water, so let him do that as you hold onto him and move around the pool or lake. Take your time and don't be too anxious to let go.
Gradually give him independence - Once he seems at ease with paddling in the safety of your grasp, begin releasing your hold for a few seconds at a time. It's too early to totally let him loose; you just want him to get used to that feeling of freedom.
Take lots of breaks - This is a stressful experience for your pup, and letting him get all worked up will defeat your purpose. After a few minutes of success, be sure to praise him enthusiastically and then take a break by holding him completely so that he does not have to paddle.
Teach him the way out - My pug loves the water but hates to swim. She does her best and strongest swimming when her session is over and we let her get out. She swims to the steps of the pool like a rocket! The incentive of letting them out of the water can be very helpful in teaching them to swim, so be sure they understand the way out. This is also a valuable safety lesson for those homes with a pool.
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