You'll probably be able to negotiate a waterway and national-park tour with a local guide, and if you call in advance, you can arrange a tour with the man considered the best guide on the Caribbean coast:
Modesto Watson, a local Miskito Indian guide. He's legendary for his bird- and animal-spotting skills as well as his howler monkey imitations. The family's Riverboat Francesca can take you up the canals for two-day-one-night excursions to Tortuguero for $175-$190 per person, depending on the lodge used.
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