The honest answer for this breed
Whether Bulldogs like swimming is almost beside the point, because Bulldogs cannot swim safely. A few individuals enjoy paddling and splashing in water they can stand in, and a curious Bulldog may wander toward a pond or pool with every appearance of enthusiasm. Physically, though, this is one of the breeds least equipped to be in deep water, and the safe assumption — the one vets and breed organisations repeat — is that a Bulldog is a non-swimmer who needs protecting around water, not testing in it.
Owners who understand why are much better placed to keep the dog safe, because the risks are built into the shape that makes a Bulldog a Bulldog.
Built to sink, and to struggle breathing
Start with the head. A Bulldog's very short, flat muzzle gives him a restricted airway, wide nostrils close to the water and no length of nose to hold clear of the surface. Swimming demands sustained, efficient breathing, and a Bulldog is working hard to breathe at rest on a warm day. Add the body: a Bulldog is dense and top-heavy, with a massive head and chest, a compact frame and relatively short legs. In deep water that mass distribution tips him forward and down; his paddling cannot generate enough lift to keep that head up, and he can go under quickly and quietly.
This is not a fitness problem that practice fixes. It is geometry and airway, and it is why Bulldog drownings in garden pools and ponds are a recurring, preventable tragedy rather than a freak accident.
What water a Bulldog can enjoy
Standing-depth is the Bulldog's water world, and many genuinely love it. A shallow paddling pool in the shade lets a Bulldog cool his belly and paws — valuable for a breed that overheats easily — while keeping all four feet on the ground. On walks, a lead-kept paddle at the very edge of a lake or stream, in water no deeper than his belly with a solid bottom, is the outdoor equivalent. He should wear a properly fitted life vest whenever there is any chance of reaching deeper water — on boats, on docks, beside unfenced ponds — because the vest is what holds that heavy front end up and gives you a handle during the seconds that matter.
Never rely on the vest to make swimming lessons a good idea. It is fall protection, not a swimming programme, and a Bulldog in water should always be within arm's reach of an adult whose only job is watching him.
Guard the water at home
The highest-risk water in most Bulldogs' lives is at home: garden pools, hot tubs, fish ponds and even deep water features. A Bulldog who falls in usually cannot climb out and cannot tread water while he waits. Fence pools, fit a rigid cover, block pond access, and treat any visit to a home with a pool as a supervision event for the whole stay — doors get left open, and this breed explores. If a Bulldog does go under, even briefly, or is found coughing and distressed after a water incident, contact a vet promptly rather than waiting to see, because breathing problems in this breed escalate fast.
Most Bulldogs are perfectly content with the paddling-pool version of summer, and miss nothing by skipping the swim. The danger comes from people who do not know the breed assuming he can manage, so KinsLe Family Sharing puts your Bulldog's non-swimmer status front and centre on his profile for anyone who cares for him.