Replied to There's a "Turkish bird-language"… on Speech to Birdsong Conversion via Hacker News:
The Silbo Gomero [1] in the Canary Islands falls in this category as well. It was designed to allow far distance communication through the valleys and ravines of the islands. Here [2] is an example.
There are now efforts to preserve the language, but there is a whole generation unable to speak it because cellphones and lack of farmers made the language almost obsolete.
[1] https://en.wikipedia.org/wiki/Silbo_Gomero
[2] https://en.wikipedia.org/wiki/File:Silbo.ogg
