This is just my personal opinion, of course, but I feel there are endless reasons *not* to release a Wailmer back into the wild.
As far as water pokemon go, they are a bit bigger than most of the common species people train, but their size has its advantages too. In terms of needing a companion to either surf or dive, Wailmer is perfectly suited for both. They are big enough to ride comfortably and can deal with most types of weather, and also strong enough to help people diving underwater. The research centre I work for has trained a small pod of Wailmer specifically as dive companions for the people that want to visit the reefs. Because of their size, it means multiple people can hold onto the same harness, and in case of emergency, they can not only defend divers from anything out on the reef, but they can also bring divers that are in trouble up to the surface in a way a smaller water pokemon couldn't.
I'm not sure if you have an intention of training your pokemon for battling, but as a battle pokemon, Wailmer has its strengths too. Like any pure water type pokemon, it only has two weaknesses. It is, admittedly, not the fastest water pokemon available, but it does have a lot of power and health on its side, which means it can outlast more fragile opponents based on that. It can learn several ice-type moves too, which means the ability to target types that are weak to ice (including grass, which it is weak to, and therefore might more commonly face in a trainer battle) but without the downsides (i.e. the low number of types it resists) of ice types.
Plus, even without those factors, they are just an amazing kind of pokemon. They are very social creatures and they live in pods in the wild. Usually, a pod will consist of several adult Wailords and young Wailmer and they will all come together to defend any member of the pod that gets attacked. Not that they have many enemies out in the wild. The young Wailmer can be preyed on by Sharpedo on occasion (though they generally prefer an easier prey) and Dhelmise will attack even a full-grown Wailord, but beyond that, they are very much at the top of the food chain out in the ocean. As far as hunting goes, they are actually really good at it. People might not expect that, as they don't have the intimidating looks of, say, a Sharpedo or a Tentacruel, but in reality, they hunt much like a pack of Mightyena. They coordinate their attacks to herd their prey together and then knock them out by leaping and crashing onto the water's surface.
But outside of that, they aren't particularly ferocious. They will defend their own, of course, but they are also incredibly kind and sweet-tempered. If you are out in the ocean diving, it is much better to run into a Wailord than a Sharpedo. At least in terms of your chances of getting attacked or chased off. Wailmer and Wailord tend to be more curious and tolerant of people's presence, probably because they have so little to fear due to their size.
They are the biggest pokemon this world as ever seen, you know. Not Wailmer, of course. But Wailords are. They commonly measure 14.5 meters from the snout to tail, but I've seen bigger ones too. They are also capable of diving extremely deep. They've been known to dive to a depth of three kilometres on a single breath.
Plus, did you know that unlike most fish pokemon, they actually have a history of living on the land? They originally lived in the ocean, evolved to live on land, and then when back into the ocean. It might sounds crazy, but it's true.
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As far as water pokemon go, they are a bit bigger than most of the common species people train, but their size has its advantages too. In terms of needing a companion to either surf or dive, Wailmer is perfectly suited for both. They are big enough to ride comfortably and can deal with most types of weather, and also strong enough to help people diving underwater. The research centre I work for has trained a small pod of Wailmer specifically as dive companions for the people that want to visit the reefs. Because of their size, it means multiple people can hold onto the same harness, and in case of emergency, they can not only defend divers from anything out on the reef, but they can also bring divers that are in trouble up to the surface in a way a smaller water pokemon couldn't.
I'm not sure if you have an intention of training your pokemon for battling, but as a battle pokemon, Wailmer has its strengths too. Like any pure water type pokemon, it only has two weaknesses. It is, admittedly, not the fastest water pokemon available, but it does have a lot of power and health on its side, which means it can outlast more fragile opponents based on that. It can learn several ice-type moves too, which means the ability to target types that are weak to ice (including grass, which it is weak to, and therefore might more commonly face in a trainer battle) but without the downsides (i.e. the low number of types it resists) of ice types.
Plus, even without those factors, they are just an amazing kind of pokemon. They are very social creatures and they live in pods in the wild. Usually, a pod will consist of several adult Wailords and young Wailmer and they will all come together to defend any member of the pod that gets attacked. Not that they have many enemies out in the wild. The young Wailmer can be preyed on by Sharpedo on occasion (though they generally prefer an easier prey) and Dhelmise will attack even a full-grown Wailord, but beyond that, they are very much at the top of the food chain out in the ocean. As far as hunting goes, they are actually really good at it. People might not expect that, as they don't have the intimidating looks of, say, a Sharpedo or a Tentacruel, but in reality, they hunt much like a pack of Mightyena. They coordinate their attacks to herd their prey together and then knock them out by leaping and crashing onto the water's surface.
But outside of that, they aren't particularly ferocious. They will defend their own, of course, but they are also incredibly kind and sweet-tempered. If you are out in the ocean diving, it is much better to run into a Wailord than a Sharpedo. At least in terms of your chances of getting attacked or chased off. Wailmer and Wailord tend to be more curious and tolerant of people's presence, probably because they have so little to fear due to their size.
They are the biggest pokemon this world as ever seen, you know. Not Wailmer, of course. But Wailords are. They commonly measure 14.5 meters from the snout to tail, but I've seen bigger ones too. They are also capable of diving extremely deep. They've been known to dive to a depth of three kilometres on a single breath.
Plus, did you know that unlike most fish pokemon, they actually have a history of living on the land? They originally lived in the ocean, evolved to live on land, and then when back into the ocean. It might sounds crazy, but it's true.