The primary draw for visitors to Guánica  is the astounding landscape of Bosque Estatal de Guánica (Carr. 334, 787/821-5706, 787/724-3724, or 787/721-5495, Mon.–Fri. 7 a.m.–4 p.m., Sat.–Sun. 8:30 a.m.–4 p.m., free). This 10,000-acre subtropical dry forest sits atop petrified coral reefs millions of years old and features a variety of environments. On the southern side you’ll find the dry scrub forest, featuring sun-bleached rocky soil, cacti, and stunted, twisted trees. There are also patches of evergreen forest along the upper eastern and western parts of the forest, where you can find Spanish moss, mistletoe, bromeliads, and orchids.
The rest of the forest has deciduous growth, where 40 percent of the trees lose their leaves between December and April. Agave and campeche trees, a source of red and black dye once exported to Europe for hundreds of years, are common to the area. Other flora among the forest’s 700 species includes prickly pear cactus, sea grape, milkweed, mahogany, and yucca. Be sure to avoid the poisonous chicharron, a shrub with reddish piney leaves that can irritate the skin on contact.
Guánica  is of special interest to bird-watchers. More than 80 species have been identified here, including the pearly-eyed thrasher, a variety of hummingbirds, the Puerto Rican mango, and the Puerto Rican nightjar, a bird that nests on the ground and remains nearly motionless all day until dusk. Other species of wildlife include the crested toad, a variety of geckos and lizards, land crabs, and green and leatherback turtles. Mongooses are also present in the area, having been introduced to the island many years ago to kill rats on the sugar plantations. The vicious little varmints are to be avoided at all costs.