Kagoshima prefecture: north central Okinawa, Oki-no-erabu island.
East Oki-No-Erabu, West Oki-No-Erabu. Inherent intelligibility generally impossible, or very difficult, with Ryukyuan languages and Japanese [jpn]. Dialect differences noticeable, but communication not impossible. Ryukyuan languages are 62%–70% cognate with Tokyo dialect of Japanese. Ryukyu languages are 62%–70% cognate with Tokyo dialect of Japanese [jpn].
Mainly adults. Also use Japanese [jpn].