What does a purple flag on a ship mean?
What does a purple flag on a ship mean? Purple Flag – Dangerous Marine Life Finally, a purple flag means that there is dangerous marine life out on the water or beach. This could mean jellyfish, stingrays, sea snakes, or other marine life except sharks.
What does a black flag on a ship mean?
The black flag was part of a flag signal combination, together with a plain red flag. After closing in on a target ship, the black flag would be raised, signaling that quarter will be given if the target crew surrendered their cargo/valuables without a fight.