1. MONA GROUND IGUANA

Population numbers for the Mona Ground Iguana (ESA Threatened) are estimated at around 5,000. Juveniles are scarce and represent only 5-10 percent of the population, resulting in an aging and declining population. Feral cats and pigs present on the island are the main cause of this species decline; both invasive species directly prey on young iguanas and their eggs. With considerable impacts to their nesting habitat due to pig predation, habitat modification, and, sometimes, limited availability of suitable nesting areas, it is essential that we remove invasive species from Mona to protect this threatened species from extinction.

2. MONA YELLOW-SHOULDERED BLACKBIRD

The population and range of the Yellow-shouldered Blackbird (ESA Endangered) has declined drastically since the middle of the twentieth century. This Endangered bird is currently confined to a small region in southwestern Puerto Rico and on Mona Island (where it is a unique subspecies). Due to nest predation from invasive rats on Mona, the Mona Yellow-shouldered Blackbird is further restricted to breeding only on steep, inaccessible cliffs on the island. Removal of invasive rats from Mona Island will provide much needed habitat for this endangered animal.
Photo: Alcides L. Morales

3. MONA BOA

The Mona Boa (ESA Threatened) is endemic to Mona Island. Due to its nocturnal habits and retiring nature, the Mona Boa has been spared from direct human impact. However, like other boas in the Caribbean, the Mona Boa suffers from habitat modification and the impacts of invasive species, like predation by feral cats. Removal of invasive species from Mona Island will relieve the boa of this threat and provide the opportunity for recovery.

4. HIGO CHUMBO CACTUS

The Higo Chumbo Cactus (ESA Threatened) is found naturally on only three islands of Puerto Rico: Mona, Monito, and Desecheo, with most individual plants found on Mona. Feral goats and pigs on Mona Island eat the cactus, while the larvae of an introduced cactus moth severely damage it. A multi year project to remove invasive species from Desecheo Island is under way by IC, DNER, and USFWS to help protect the cactus. With every passing year, the Higo Chumbo Cactus numbers continue to increase. Removing invasive species from Mona Island will have a similar positive impact.

5. HAWKSBILL SEA TURTLE

Mona Island supports the largest Hawksbill Sea Turtle (ESA Endangered) nesting ground in the Caribbean. Feral pigs on Mona dig up nests and eat eggs and hatchlings. In 1984-1985, an exclusion fence was built to protect the turtles. Prior to the fence, 44 to 100 percent of sea turtle nests were destroyed every year due to feral pigs. While the fence has improved nesting habitat, it requires maintenance, is not a permanent solution, and does not protect all nests. The removal of feral pigs from Mona Island is required to permanently protect this important Hawksbill Sea Turtle population.