Originally broadcast as an episode of the television program, The nature of things, and released on videocassette in 1993.
Originally produced by: Canadian Broadcasting Corporation, ©1993, and broadcast as an episode of the television program, The nature of things; previously released in 1994.
Title from title frames.
Photographed by Neville Ottey ; edited by Alan Gibb ; original music, John Cheesman.
Description based on online resource; title from title frames (Docuseek2, viewed May 31, 2019).