The invasive spectacled caiman (Caiman crocodilus) in Florida, United States: invasion timeline, insights, and implications for Everglades restoration

The spectacled caiman ( Caiman crocodilus ) is a crocodylian native to Central and South America that has been introduced and established (reproducing in the wild) in several insular (i.e., Cuba, Puerto Rico, San Andres) and continental (i.e., Florida) areas out of its native range. The hypothesized impacts associated with spectacled caiman invasion are numerous, including competition with other native aquatic predators (i.e., American alligators/American crocodiles), predating upon sensitive species (i.e., Nerodia sp.), and causing overall food web structure modifications. Nonetheless, the lack of ecological studies testing these hypotheses limits quantification of those impacts. This review focuses on what we have learned about spectacled caiman’s biology, ecology, distribution, and ecological impacts in the past 45 years since establishment in South Florida, United States (US), management approaches so far implemented, and the future of its management in the context of Everglades restoration. Spectacled caiman rapid establishment in South Florida can be attributed to a presumably large initial population (at least couple of pairs), small-sized reproductive specimens, broad adaptability to various habitats, and favorable temperatures. Recent observations suggest that spectacled caiman distribution may expand further within protected areas/natural habitats (i.e., Everglades National Park), which would make management and control more difficult, increasing the risk of potential harmful effects on sensitive ecosystems (i.e., wilderness areas). We present insights into spectacled caiman’s habitat, seasonal dynamics, and influence in trophic interactions within native aquatic communities in South Florida. We also discuss the implications of spectacled caiman management and control in Everglades restoration and the potential effects of hydrological restoration on the future of this invasive species. The objective of this research was to provide up-to-date pieces of information on spectacled caiman ecology, management, and policy, including new data on nesting and potential trophic interactions collected through monitoring and participatory research. We also highlight knowledge gaps and research priorities for future studies to better assess spectacled caiman impacts on the invaded ecosystems.