As per this post, I'm going to be running a brief vignette on the high seas. The kick is, this is in fact a vast inland sea, effectively a giant freshwater lake.
D20srd.org doesn't distinguish between freshwater and saltwater aquatic terrain for beastie listings, so one wonders...
Is it reasonable to assume that large scale animals such as sharks and whales would evolve/adapt to freshwater environments if the sea is big enough to support such ecologies? I know I can resort to the "because I said so" rule, but I wonder if there are any such instances in the real world?
The premise is that the group has hired a fishing vessel to transport them a week's travel along the coastline closer toward their inland destination. This came about from seat of the pants GMing when they disdained the two land-based courses I'd prepared for.
The vessel is not large, crewed by only a dozen or so; but I can't imagine fishing boats going out for weeks at a time unless they're hunting specific delicacies; after all, in an age without refrigeration, who wants to spend days at a time on a boat filled with dead fish?
So I thought, what if they bribe the local authorities to turn a blind eye toward smuggling activities in exchange for some rare kind of meat, like shark or a small whale - nothing so big as to present a dire risk to the ship and crew (like kraken or giant squid), and something that can be harpooned with only average challenge.
Any thoughts? Effectively what I'm trying to come up with is a non-threatening encounter that logically explains the viability of the trip.