page_title: Blakiston's Line
section_title: Species North and South of Blakiston's Line
hierarchical_section_title: Blakiston's Line / Species North and South of Blakiston's Line
caption_attribution_description: English: Blakiston's Fish Owl - (Bubo blakistoni)
context_page_description: The Blakiston Line or Blakiston's Line is a faunal boundary line drawn between two of the four largest islands of Japan: Hokkaidō in the north and Honshū, south of it. It can be compared with faunal boundary lines like the Wallace Line. Certain animal species can only be found north of Blakiston's Line, while certain other species can only be found south of it.
  Thomas Blakiston, who lived in Japan from 1861 to 1884 and who spent much of that time in Hakodate, Hokkaido, was the first person to notice that animals in Hokkaidō, Japan's northern island, were related to northern Asian species, whereas those on Honshū to the south were related to those from southern Asia. The Tsugaru Strait between the two islands was therefore established as a zoogeographical boundary, and became known as Blakiston's Line. This finding was first published to the Asiatic Society of Japan in a paper of 14 February 1883, named Zoological Indications of Ancient Connection of the Japan islands with the Continent.
context_section_description: Besides birds, animals that are of different origins north and south of the Blakiston Line include wolves, bears and chipmunks. Monkeys do not even live north of Blakiston's Line. The following table gives some examples of animal species involved:
  Note that species that can only be found on the Ryukyu Islands are excluded from this table, even though their habitat is clearly south of Blakiston's Line, as other factors account for their distribution. Besides animal species that can only be found either north or south of Blakiston's Line, there are very many that can be found at either side of the line, in part because of human involvement. Examples of the latter are the Japanese Shorthorn, a breed of small Japanese beef cattle that is distributed in northern Honshu and also in Hokkaido, and the Japanese weasel, which was introduced to Hokkaido by human intervention.
  It has also been studied whether or not this biogeographic boundary applies to far smaller organisms like soil microbes.
caption: Example of Blakiston's Fish Owl which was named after Blakiston
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