In 1896, he was made head of the fur-seal commission and signed, on behalf of Japan, a treaty with the United States and Great Britain.

In 1901 he became dean of the college of science of Tokyo University, and in 1907 he was decorated with the Order of the Sacred Temple in recognition of public service.

He was regarded not only as one of the leading zoologists of Japan, but also as very influential in public life.

His most important zoological publications, a series of papers on the embryology of the turtles, appeared at intervals from 1886 to 1896.

[1][2] Mitsukuri also brought the "holotype" goblin shark to the California Academy of Sciences where the genus was named after himself and the specimen trader Alan Owston, with the scientific name Mitsukurina ownstonii.