As you can see from this sign, the fishermen believe they "own" the wild dolphins they trap in Taiji's cove.
Obviously, even if this were the case, that would not entitle them to treat the dolphins and whales in the cruel way they do.
But leaving this aside, the simple fact is that these animals are not owned by Japan, let alone the local Taiji fishermen's association. They do not even live in Japanese waters, but merely pass along Japan's coast.
Not much is known specifically about the migration routes of dolphins and small whales. We do know that large whales are capable of mammoth journeys. For example, humpback whales travel 10,000 km between breeding areas.
But what of the dolphins and whales captured at Taiji? Dolphins are thought not to make extensive journeys between geographical areas as large whales do, but they are capable of travelling very long distances. One bottlenose dolphin tracked off the coast of Florida, for instance, travelled 4,200 km in 47 days. This is the distance, for example, between southern Japan and northern Australia.
We don't know how far the dolphins and whales travel in their migrations, or which countries or oceans they might visit. But we can say with certainty that these wonderful animals are citizens of the entire planet, and are not owned by Japan for its exclusive, commercial and cruel advantage.