Omniscient French Capitaine?

With the Acheron in pursuit of the now disguised Surprise/Syren, why does the French capitaine bellow through the megaphone "ENGLISH WHALER SYREN ..."??? (at 1:49:44 and again at 1:49:58 of the movie's run time). Does he recognize Jack's long, sans chapeau, yellow(?) hair from their earlier meetings? Was the Surprise's crew's disguise that poor that the Frenchy saw right through it? (The Syren was flying the Brazilian flag!) Maybe just a script flub-up?