I imagine

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Note added at 37 mins (2005-02-26 17:44:32 GMT)
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perhaps ferry/ferries is the more neutral term in the context

speaking of google, I tried the following: "bateau-navette" + english;
took me to a number of french sites using the word but which also have an english version; they most simply use "boat" as a term.
Think of it. Context playing a large part in all of this, it is almost redundant, given the fact that, what boats actually do, is shuttle or ferry people, whether in large numbers with their automobiles or simply two people (operating their own cris-craft.
I think the essence here is boat and not necessarily ferry (whihc in certian coutnries like Canada is called traversier).
check out these links:

I don't know of an exact English equivalent term, so I think it may depend a bit on exactly WHAT these boats' function is; if they are genuinely operating a 'shuttle service between (say) 2 ports, then they would be 'ferries' or 'ferry-boats' if you prefer. If on the other hand they are simply sight-seeing boats, it might be a bit more difficult; in ilden days it could have been 'pleasure steamer', but that delightful term is too antiquated now, especially as I presume they are not steamboats! 'Pleasure boats', on the other hand, suggests instead smaller, private boats/yachts, which of course would not be the sense here.
'Pleasure cruisers' might be considered sufficiently vague to be able to encompass tourist boats as well as private yachts, though I would have some reservations about this term too.
Maybe your continuing context will give you a bit more detail about what they actually do?

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Note added at 19 mins (2005-02-26 17:27:13 GMT)
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Well, I don\'t think the distance they go from the coast makes a lot of difference to the term --- in fact, I\'d say the FURTHER they go, the more likely they are to be ferries --- think of a cross-Channel ferry --- certainly couldn\'t call THAT a \'shuttle\' --- though interestingly enough, the cross-Channel tarins ARE called shuttles! Hence why I say that \'ferry\' keeps a more nautical ring, whereas \'shuttle\' sounds like a landlubber\'s term for the kind of to-and-for service often provided by buses to and from airports, etc.


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Note added at 24 mins (2005-02-26 17:32:03 GMT)
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In answer to Michel\'s comment response:

I don\'t like getting into the \"who\'s got the biggest Google?\" game, but just by way of balance, I\'d point out that ferry got me 13,880,000 hits, ferry-boat 442,000, and shuttle-boat a measly 17,600 ;-)

A quick skim through the first few indicated that, as I suspected, a lot of \'shuttles\' are in fact hotel-specific courtesy shuttles (which I don\'t think it is safe to assume they would be in Asker\'s context), whereas quite a few hits for ferry mention \'sight-seeing\', à la bateaux mouches in Paris, for example.

So I feel more than ever convinced that \'ferry-boat\' or \'ferry\' is an appropriate term here.

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Note added at 6 hrs 36 mins (2005-02-26 23:44:05 GMT)
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Thanks to Peekay for adding a whole new dimension to the discussion: supposing the author is NOT referring to commercial boats fulfilling a specific function, but rather to a constant passage of (motorized)boats plying to and fro, any of which might create enough wash to upset a fragile canoe.

To this extent, I agree that \'boats\' alone might suffice, if one can assume that the \'navette\' is a purely figurative idea. However, I feel that using just \'boats\' alone dreadfully weakens the strength of the original, so I would avoid it if at all possible...