From Atlas Obscura: The Child-Eating Bunyip Haunts Australia’s Wetlands
https://www.atlasobscura.com/articles/murray-river-bunyip-australia-swamp-monster
Of course, the article has mention of the 1978 chidren's book "The Bunyip of Berkeley's Creek", which is a book I grew up with as a kid and love (it was given to me when it was first published).