Hi Azizi
Hugil does list Dou Dou in his Glosary

DuoDuo - A West Indian Creole word meaning "sweetheart".

"Roller Bowler (p. 260) or "Good Morning Ladies All" from which comes the line I quoted
"As I roved out one morning
away you roller bowler
I met a duo dou fair"

Hugill says "Another shanty which the expression 'high-rig-a-jig' is the capstan song "Roller Bowler" which appears to me to be (notice that he says "appears"-my comment) another of the Negro-Irish type of sailor work-song. I picked up my version out in Trinidad. Sharp's version, the only one in print until now, seems to be a Liverpool shanty although he collected it in Bristol, I think. Anyhow it is definitely a shanty that was sung aboard of the West Indian Sugar & Rum Traders, since it was well known by most of my West Indian shipmates".
Hugil has 3 versions of "Good Morning Ladies All" all from West Indian sources.

"Darling do do I'm going to St Peter's"
Darling do do I'm taking you with me"

This verse comes from Roger Abrahams "Deep The Water Shallow The Shore"
(Roger collected from the Islands of Nevis, Tabago & St. Vincent in the early 60's)
During the 'Fishermen's Fete', (on) St Peter's day June 29, each of the beach singers feels that he must make up a song for the visiting fishermen who come from all over the island. They commonly sing of the beauties of the fete, using a traditional tune bit introducing topical subjects & an appropriate chorus line. Here is a pattern, for instance, which was improvised upon by one of the singers the year before we lived in Plymouth.

So "duo dou" was still in the common vocabularly at the time.

Now I don't say that "dou dou" & "doodle" were interchangable or that "doodle" came from "dou dou" but an ear not accustom to the local slang such as a transient sailor,,,,,,,,,,,,,,,?????????

Barry