A few nice names for animals images I found:
Whale & Walrus Bacula
Image by Travis S.
Baculum is the name for an animal's penis bone.
Oosik is an Alaska Native termed used for the same object of large arctic mammals.
Above is a walrus oosik which can get to about 2 feet (60cm) long and could be used for a variety of things including war clubs. Below that is a whale oosik, (maybe of a bowhead?) which looks to be about 5 feet (150cm) long.
I've never seen one of these before or read or heard about them in the literature.
See a different view focusing on the proximal portion.
This is at Ye Olde Curiosity Shop.