The tiny Garifuna fishing community of Barranco (population 160), about an hour's drive from Punta Gorda, is the access point for Temash-Sarstoon National Park, a remote 64-sq-mile protected reserve of rainforest, wetlands, estuaries and rivers lined by towering mangroves and stretching all the way to Guatemala. The park harbors a huge variety of wildlife including jaguars, tapirs, ocelots, birdlife and manatees in the estuaries.
Two Barranco natives deeply involved in both local tourism and park conservation are Egbert Valencio and Alvin Loredo; both lead land and river tours (around BZ$200 per day) into the nearby park given at least a few days' notice.
Ask in Punta Gorda about the boat service to Barranco that was mooted when we visited.