Workers from Osaka Aquarium Kaiyukan had approached the large mammal to check if it was breathing, while a researcher also said the whale's blowhole had been submerged since Wednesday.
An 8-meter-long whale spotted near the mouth of the Yodo River in Osaka earlier this week was confirmed dead on Jan. 13, local officials said, after it had remained in the same spot for days and was not observed spouting water.