Not necessarily. If it's not important to the reader to know how she got on the boat, don't bother with. If it is important to the reader, you could use this approach:

{ON SHORE}
SHE: I must take action to solve my dilemma!

{ON BOAT}
SHE: Hey, I'm on a boat.
ROBOT BARTENDER ON THE LUAU DECK: So, what brings you onboard?
SHE: Funny story. (tells)
ROBOT BARTENDER ON THE LUAU DECK: Outta sight!