Boasting

Four longships are drawn up on the beach at the head of an ice-bound fjord, and their owners are whiling away a long winter evening with a moustache contest. They are each telling of a hair-raising scrape they got into on the high seas during the previous summer, exhibiting their scars as proof of their bravery (or their lack of scars, as proof of their cleverness). These are the facts:

• Bjarni "the Clever" escaped unwounded
• The man who killed a huge shark has a smaller moustache than the man who owns the Ocean Jarl
• Hrolf owns the Black Serpent
• The man who killed a sea sleen has a bigger moustache than the man who was wounded in the arm
• Oddi killed a man-eating whale
• Sven has the next bigger moustache than the man who owns the Marauder (who isn't Bjarni)
• The man who was wounded in the arm has the next bigger moustache than the man who owns the Merciless
• The man with the smallest moustache killed a giant squid
• The man who owns the Ocean Jarl has the next bigger moustache than the man who was wounded in the leg

Who was wounded in the head?