Answer:
zero
Explanation:
There is no way for them to hit each other's ships if the pirate shoots first and they each shoot once. In the description of the question, it says that if the Captain's ship is hit, then he will always miss his next shot. So if they each shoot once, and the Pirate hits the captain's ship, the Captain will always miss, so there is no way he will hit the Pirate's ship in return.