I mean the other names make sense with additional context
Both Tit- and Cock- as prefixes used to mean small (no laughing in the back, please)
And Hoary means grey-haired or old-looking
edit as I had to look this one up: “Booby” is an ellision of “Bobo” - as in “No seas tan bobo” (Spanish) - meaning “silly, naive, dumb…” as they tend to be quite tame birds