No it doesnt
Technically they would consider it nakama but its still their ship,not a nakama like a living being
Except.. arguable in the context of this specific Manga... the ship
is in fact a person, and
has a soul, as well as a voice that can communicate with the crew in dire circumstances when absolutely needed. Even appeared in a human like form in front of Usopp, talked to all of them later.
Appeared in his human like form again in a TV-Special observing them.. they
do have a living guardian spirit following them, and living with them, and they consider that ships-spirit... what-ever.. that was created with Merry and moved along to Sunny, a Nakama..
It's a tiny bit ambegious, but I think it can be argued that there is an alive spirit, with a mind, soul, voice and every-thing of its own, called Merry, that follows them around as a bonus Nakama, protecting them when needed.
At least that must count for half a nakama, right!?
And before any-one says. "But it's just a ship!" .. every-one are just drawings in the harsh reality of things, and in the context of the manga, that ship is a darn person!
I've cried more over that damn ship than i've done over death of main characters in other fictional medias... darn it.
