Today’s BC strip invokes the myth, prompting one commenter to use Snopes as a source to claim that the myth originated with the White Wilderness “documentary”. This, of course, is not true.
The way I understand it, the documentarians believed it really happened, and that’s why they faked it, after having hoped they could make it happen spontaneously and failed.
As Snopes says, faking stuff for nature documentaries was not uncommon, and most of the other films by Disney were faked, too.