Hello Bearbait!
I know of a few cases of melanistic african leopards that were shot by hunters. It seems that they are sometimes seen high up in the mountains, mainly in Ethiopia and Kenya. In Asia, black leopards are apparently not so rare.
One black Leopard was taken years ago by a spanish client of PH Nassos Roussos in Ethiopia.
The well-known PH John Kingsley-Heath shot a black Leo, also in Ethiopia. He writes that the colour of the pelt started to fade after some years and was finally a chocolate-brown.
There's a picture of Elgin Gates and a black leopard pelt in his book "Trophy Hunter in Africa", i think it was taken in Kenya while Bongo hunting. Will have to look if Gates also writes about this Leopard, i only found the photo.
Thorold Murray-Smith, one of the oldtime White Hunters in East Africa, writes in his book "The Nature of the Beast" that he saw black Leopards on three different occasions! This must be a record, so many experienced hunters never saw a single one! Anyway, those cats were so beautiful, that Murray-Smith always refused to shoot and let them go...
And i remember the case of a black leopard killing gorillas in the Uganda Mountains. The story was repeatedly told by Walter Baumgartel, a german who had a resthouse there in the 1950s-1960s. Story is also in Brian Herne's "Uganda Safaris".
But black leopards are nothing, compared to the story of a BLUE TIGER in China, a man-eater as well, who ate several Chinese in the 1920s. The beast was tracked and hunted by the American hunter and missionary Harry Caldwell and his friend, explorer Roy Chapman-Andrews. Both men failed to killed the tiger, but Caldwell wrote the book "Blue Tiger" about it. Great story.
Best wishes:
Kouprey