The northernmost 100 acres of the island constitute the Caye Caulker Forest Reserve, declared in 1998. Birdlife is prolific in the reserve, particularly wading birds, such as the tricolored heron, and songbirds, including the mangrove warbler. Somewhat rare species that can be spotted include the white-crowned pigeon, rufus-necked rail and black catbird. Inland lagoons provide habitat for crocodiles and turtles, five species of crab, boa constrictors, scaly tailed iguanas (locally called 'wish willies'), geckos and lizards.
The littoral forest on Caye Caulker is mostly red, white and black mangrove, which grows in the shallow water. The mangroves' root systems support an intricate ecosystem, including sponges, gorgonians, anemones and a wide variety of fish. Besides the mangroves, the forest contains buttonwood, gumbo-limbo (the 'tourist tree'), poisonwood, madre de cacao, ficus and ziracote. Coconut palms and Australian pines are not native to this region, but there is no shortage of them.
The forest reserve is an excellent, but very challenging destination for kayakers. You may prefer to paddle up the calmer, west side of the island to avoid strong winds and rough seas. There's also an excellent new tour with Richard's Adventures that brings intrepid guests along a 1.5km boardwalk through the crocodile habitat.