Name of book about boy fighting alligator in Everglades. I think Ironsides or Old Ironsides? Meets seminoles?

The boy and his family move there and he hates it at first. Then he starts poling around the Everglades and decides it is ok. Makes friends with a Seminole boy. I read it back in the 60's. I think the name was Ironside. The picture on the front shows him standing up in the dugout and the big alligator coming up out of the water. I sure would love to have this book again