Unless I'm mistaken, there's no evidence that Bert Lloyd collected his great version of "The Coast of Peru" from a human being. Though Lloyd worked on a whaling ship for a short time in the 1930s, his album notes to Leviathan and There She Blows! say nothing about hearing the song then or, in fact, at any time anywhere.

He almost certainly learned it from print and added collations and improvements of his own.

But where did he get the outstanding tune? Colcord's is different.
Is it a close relative of a traditional tune?