Ok, well in a strait fight you are probably right, the Ninjas win.
BUT, Ninjas have a problem. They are hired assassin. This will cause them trouble.
Let me out a scenario.
The Governor of a small island is pissed that his only daughter is sleeping around with a dirty Pirate. He hears about these so called Ninjas and hires them. Well while he is going over the price the daughter over hears what is going on. She goes to her Pirate lover and tells him.
The Pirates know what is coming and can prepare. First that go kidnap 50 hot chicks, and then chain them naked to the deck of the ship. Then they get the parrots off the booze, and start feeding the monkeys Lute fish. This will make the Monkeys poo extra potent.
Then they prepare the ambush.
Now when the Ninjas show up, they will see all these naked western women and it will put there training to the test, see Ninjas don’t get laid much, because they have to train all the time. They are either training, killing or rocking out. No time for broads.
They will freeze when confronted with all this easily had women flesh.
That’s when the parrots, monkeys and Pirates swing into action, taking the stunned Ninjas out.
Victory Pirates.