Hei Hu, Blue Tiger and Black Blue Tiger are actually the same thing, because their fur is light black, slightly gray-blue, with dark black stripes on it, so their names are different. Tiger's coat color is well known to the world. It's yellow with black stripes on it. The blue tiger is said to have been produced in Fujian and was hunted in 1922. Cadville, who shot many tigers in Fujian, wrote a book called Blue Tiger. No new discoveries have been made since then.
History of Black, Blue and Tiger:
Hei Hu or Blue Tiger has never been exhibited in any zoo in the world, so whether they exist in the world is still an unsolved mystery. At the end of the Qing Dynasty, it was discovered by western missionaries in Beijing Xiyuan (with China Elk), and then bribed the Guards to get two pieces of blue and purple tiger skins, which were considered to be mutant individuals in royal captivity, but they never survived. They died out in China with the Elk, and did not recognize the existence of blue and purple tigers.
There are records about Hei Hu in China's ancient books: in the first dictionary of China, Shuowen Jiezi, it is said that Lin and Hei Hu are also involved. The first dictionary "Er Ya Shi Beast" was also recorded by Lin and Hei Hu, which was later found in many ancient books and distributed in Hubei, Henan, Sichuan and other places. It is said that in the Qing Dynasty, it was once found in Dongling forest area of Hebei Province, where hunting was forbidden, and it was hunted twice in 1905 and 19 12, respectively. Since then, news has piled up. Now extinct.
Reference to the above content: Baidu Encyclopedia-Black Blue Tiger