The American Crocodile in Biscayne Bay, Florida

Abstract

Intensive crocodile monitoring programs conducted during the late 1970s and early 1980s in southern Florida resulted in an optimistic outlook for recovery of the protected species population. However, some areas with suitable crocodile habitat were not investigated, such as Biscayne Bay and the mainland shorelines of Barnes and Card Sounds. The objective of our study was to determine status and habitat use of crocodiles in the aforementioned areas. Spotlight and nesting surveys were conducted from September 1996 to December 2005. The results revealed annual increases in the number of crocodiles. Crocodiles preferred protected habitats such as canals and ponds. Fewer crocodiles were observed in higher salinity water. The distribution and abundance of crocodilians in estuaries is directly dependent on timing, amount, and location of freshwater delivery, providing an opportunity to integrate habitat enhancement with ongoing ecosystem restoration and management activities.

Population assessment of the American crocodile, <i>Crocodylus acutus</i> (Crocodilia: Crocodylidae) on the Pacific coast of Costa Rica

“…Therefore, they may be underestimated in this study. This low number of adults is consistent with the results of other studies (Webb et al 1984, Kushlan & Mazzotti 1989a, Ouboter & Nanhoe 1989, Stuebing et al 1994, Read et al 2004, Cherkiss et al 2011 and could be indicative of a recovering population (Ouboter & Nanhoe 1989). If hatchlings were excluded, roughly 40% of the entire coast and each of the Northern populations were composed of juveniles.…”

“…This species ranges from the extreme Southern tip of Florida, throughout the Caribbean and along the Pacific and Caribbean coasts of Central and Northern South America (Thorbjarnarson et al 2006, Thorbjarnarson 2010. Crocodylus acutus is considered a coastal species, inhabiting lagoons and estuaries, areas with lower salinities and can also be found inland along major rivers and land-locked lakes (Kushlan & Mazzotti 1989a, Platt & Thorbjarnarson 2000, Thorbjarnarson et al 2006, Mazzotti et al 2009, Cherkiss et al 2011. Crocodylus acutus can also be found in marine habitats (full-strength sea water) along offshore islands and atolls (Platt & Thorjarnarson 2000).…”

Life histories and conservation of long‐lived reptiles, an illustration with the American crocodile (Crocodylus acutus)

“…The American crocodile has adapted to the man‐made conditions at Turkey Point (Cherkiss et al., ; Mazzotti, ; Mazzotti et al., ) and has experienced an estimated average growth rate of 4% annually, based on our models, since the first hatchlings were discovered in 1978 (Brandt et al., ; Gaby et al., ). Continued protection of the American crocodile and its nesting and coastal habitats are important, particularly in south Florida where monitoring and management efforts have had a positive impact on the conservation status of this threatened species (Mazzotti et al., ).…”

“…We recorded crocodile capture histories and included events from 1978 to 1981 (Gaby et al., ), 1983 to 1993 (Brandt et al., ), 1993 to 2009 (conducted by Florida Power & Light Co.) and 1996 to 2005 (Cherkiss, Romañach, & Mazzotti, ), largely targeting the hatching season from June to September. The first non‐hatchling crocodile was captured in 1983 (Brandt et al, ).…”

Crocodylus acutus (American crocodile) bite marks on a nest data logger

“…Therefore, monitoring microenvironmental conditions in the nest, especially temperature and moisture, is a critical component of conservation efforts focused on this species. In Florida, C. acutus populations have been expanding thanks to targeted conservation efforts (Kushlan, 1988;Mazzotti, 1989;Mazzotti et al, 2007b;Cherkiss, Romañach & Mazzotti, 2011), leading to the species being reclassified from endangered to threatened in 2007 (Federal Register 72:13027-13047). As part of ongoing monitoring of C. acutus, we placed data loggers in active nesting sites in 2017.…”