Crocodylus acutus - (Cuvier, 1807)
American Crocodile
Other English Common Names: American crocodile
Taxonomic Status: Accepted
Related ITIS Name(s): Crocodylus acutus Cuvier, 1807 (TSN 174361)
Spanish Common Names: Cocodrilo de Tumbes
Unique Identifier: ELEMENT_GLOBAL.2.106064
Element Code: ARABB02010
Informal Taxonomy: Animals, Vertebrates - Crocodilians
Image 12065

Public Domain

 
Kingdom Phylum Class Order Family Genus
Animalia Craniata Crocodylia Crocodilia Crocodylidae Crocodylus
Genus Size: C - Small genus (6-20 species)
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Concept Reference
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Concept Reference: King, F. W., and R. L. Burke, editors. 1989. Crocodilian, tuatara, and turtle species of the world: a taxonomic and geographic reference. Association of Systematics Collections, Washington, D.C. 216 pp.
Concept Reference Code: B89KIN01NAUS
Name Used in Concept Reference: Crocodylus acutus
Taxonomic Comments: No subspecies are recognized, although geographic variation exists among populations in Florida, Jamaica, and the Pacific coast. Populations in Florida, Jamaica, and the Dominican Republic differ from each other in their gene frequencies (Menzies and Kushlan 1991). Densmore and White (1991) used molecular data to assess phylogenetic relationships within the Crocodylia, including all species in the genus Crocodylus; the closest relative of C. acutus was C. intermedius by one analysis using rDNA, C. moreletii by another analysis that used both rDNA and mtDNA; overall, New World species of Crocodylus appeared to be more closely related to each other than to species in other parts of the world. See Ernst et al. (1999) for further taxonomic discussion.

Milián-García et al. (2011) examined microsatellite loci plus DNA sequence data from nuclear (RAG-1) and mitochondrial (cytochrome b and cytochrome oxidase I) genes of Crocodylus acutus and C. rhombifer from Cuba. They found that C. acutus from Cuba is more closely related to C. rhombifer than to C. acutus from Central America. Thus current taxonomy does not appear to be an accurate reflection of evolutionary relationships. The researchers also found evidence of hybridization between the two species in Cuba. Further study is needed before taxonomic issues can be resolved. (Milián-García et al. 2011).
Conservation Status
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NatureServe Status

Global Status: G2
Global Status Last Reviewed: 19Feb2014
Global Status Last Changed: 23Oct1996
Rounded Global Status: G2 - Imperiled
Reasons: Range extends from Mexico and southern Florida to northern South America; populations are small and declining throughout most of range; some populations have been extirpated, and poaching for hides outside the United States continues to pose a major threat.
Nation: United States
National Status: N2 (11Feb2009)

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States Florida (S2)

Other Statuses

U.S. Endangered Species Act (USESA): LE, LT: Listed endangered, listed threatened (20Mar2007)
Comments on USESA: U.S. Fish and Wildlife Service (USFWS 2007) reclassified the American crocodile (DPS) in Florida from endangered to threatened. The status of the American crocodile throughout the remainder of its range, as described in the December 18, 1979, final rule, remains endangered.
U.S. Fish & Wildlife Service Lead Region: R4 - Southeast
IUCN Red List Category: VU - Vulnerable
Convention on International Trade in Endangered Species Protection Status (CITES): Appendix I

NatureServe Global Conservation Status Factors

Range Extent: >2,500,000 square km (greater than 1,000,000 square miles)
Range Extent Comments: Range extends from southern Florida, Sinaloa (Mexico), and Yucatan (Mexico) south through Middle America (Pacific and Atlantic) and the West Indies to northern South America (to northern Peru and Venezuela) (Ernst et al. 1999).

Florida: Historical range centered on the southern tip of mainland Florida but extended at least as far north as Sanibel Island and Sarasota County on the west coast and Indian River County on the Atlantic coast, and southward into the Florida Keys (USFWS 2007). The primary historical nesting area in Florida was on the mainland shore of Florida and Biscayne bays, including many of the small islands near shore, in what is today Everglades National Park, and it also included the upper Florida Keys from Key Largo south to Lower Matecumbe Key (see USFWS 2007). Today most nesting occurs on the mainland shore of Florida Bay between Cape Sable and Key Largo, but the nesting range also includes Biscayne Bay and the upper Florida Keys, with unsuccessful nesting north to Marco Island (USFWS 2007).

Middle America: both coasts from Mexico south to Panama. See Kaiser et al. (2001) for information on a breeding population on Roatan, Honduras.

Antilles: Cuba (Isla de la Juventud, and nearby islands), Hispaniola, Jamaica (along south coast and is especially abundant in marshes of Black River in west), Martinique, and Maragarita. The population in Cuba is of uncertain taxonomic status (see Mili n-Garc¡a et al. 2011 and taxonomy comments).

Northern South America: Venezuela, Colombia, Ecuador, and northern Peru.

Occasional vagrant to Cayman Islands (Schwartz and Henderson 1991).

Area of Occupancy: Unknown 4-km2 grid cells
Area of Occupancy Comments:  

Number of Occurrences: 21 - 80
Number of Occurrences Comments: This species is represented by at least several dozen occurrences (subpopulations). Occurrences are discontinuous. Most are small, isolated, and in remote areas.

Population Size: 2500 - 100,000 individuals
Population Size Comments: Total adult population size is unknown but presumably exceeds 2,500 and may exceed 10,000.

The American crocodile population in Florida has grown to an estimated 1,400 to 2,000 individuals, not including hatchlings, with 91-94 documented nests in 2005 (see USFWS 2007).

As of the 1990s, perhaps 200 adults and subadults existed in the Dominican Republic (Schubert 1994). Others are scattered throughout the range.

Number of Occurrences with Good Viability/Integrity: Few to some (4-40)
Viability/Integrity Comments: Most subpopulations probably have less than good viability.

Overall Threat Impact: Very high - high
Overall Threat Impact Comments: Major threat in most parts of the range is poaching for skins. In some areas, populations have declined as a result of killing for meat or fat, killing for "fun," collection of eggs, and entanglement in fishing gear (Schubert 1994). Habitat loss is also a threat, especially in Florida. Nesting sites and non-nesting habitat have been lost to development at Miami Beach and in the upper Florida Keys, but this loss has been partially offset by creation of artificial nesting sites on spoil banks along southern Biscayne Bay and a westward addition to nesting range in Florida Bay (Kushlan and Mazzotti 1989). Future threats in Florida include stochastic natural disasters such as hurricanes and cold weather, road mortality, continued habitat degradation, and poaching (USFWS 1998). Crocodiles are sensitive to human presence (especially at nest sites). In Florida, disturbance at nest sites caused females to abandon the site (Kushlan and Mazzotti 1989).

In Florida, crocodiles remain threatened by modification of habitat because of development adjacent to crocodile habitat; they will benefit from restored freshwater flow into estuaries (Mazzoti et al. 2007). As crocodiles increase in abundance and expand into new areas, interactions with humans will occur more frequently; integration of a recovering crocodile population with ever-increasing human use of coastal areas is a major challenge (Mazzoti et al. 2007).

Short-term Trend: Decline of 10-70%
Short-term Trend Comments: Range-wide trends are poorly documented, but in most of the range this species undoubtedly has declined in population size over the past three generations (three generations is at least 45 years and may be as high as 60-75 years).

In Florida, extent of occurrence, area of occupancy, population size, nesting range, and number of known nests have been increasing in recent decades (Mazzoti et al. 2007, USFWS 2007). The maximum number of nesting females in Florida increased from 20 in 1975 to 85 in 2004 (Mazzoti et al. 2007).

See Schwartz and Henderson (1991) and Thorbjarnarson (1988) for information on status in Haiti.

Long-term Trend: Decline of 30-90%
Long-term Trend Comments: Area of occupancy, number of subpopulations, and especially population size have undergone a major long-term decline, but the degree of decline is uncertain.

Other NatureServe Conservation Status Information

Inventory Needs: Precise distribution and status of populations outside the United States need to be determined.

Protection Needs: Crocodile habitat in Florida continues to need maintainance and enhancement to provide protection for all life stages of the existing crocodile population and to ensure that available habitat can support population growth and expansion (USFWS 2007). Further acquisition of nesting and nursery sites and additional crocodile habitat by federal, state, and local governments and implementation of management on these publicly owned
properties are necessary to ensure protection to crocodiles and their nests and enable expansion of populations size and distribution (USFWS 2007).

Protection from poaching is critical in many parts of the range.

Distribution
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Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) Range extends from southern Florida, Sinaloa (Mexico), and Yucatan (Mexico) south through Middle America (Pacific and Atlantic) and the West Indies to northern South America (to northern Peru and Venezuela) (Ernst et al. 1999).

Florida: Historical range centered on the southern tip of mainland Florida but extended at least as far north as Sanibel Island and Sarasota County on the west coast and Indian River County on the Atlantic coast, and southward into the Florida Keys (USFWS 2007). The primary historical nesting area in Florida was on the mainland shore of Florida and Biscayne bays, including many of the small islands near shore, in what is today Everglades National Park, and it also included the upper Florida Keys from Key Largo south to Lower Matecumbe Key (see USFWS 2007). Today most nesting occurs on the mainland shore of Florida Bay between Cape Sable and Key Largo, but the nesting range also includes Biscayne Bay and the upper Florida Keys, with unsuccessful nesting north to Marco Island (USFWS 2007).

Middle America: both coasts from Mexico south to Panama. See Kaiser et al. (2001) for information on a breeding population on Roatan, Honduras.

Antilles: Cuba (Isla de la Juventud, and nearby islands), Hispaniola, Jamaica (along south coast and is especially abundant in marshes of Black River in west), Martinique, and Maragarita. The population in Cuba is of uncertain taxonomic status (see Mili n-Garc¡a et al. 2011 and taxonomy comments).

Northern South America: Venezuela, Colombia, Ecuador, and northern Peru.

Occasional vagrant to Cayman Islands (Schwartz and Henderson 1991).

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map
Endemism: occurs (regularly, as a native taxon) in multiple nations

U.S. & Canada State/Province Distribution
United States FL

Range Map
Note: Range depicted for New World only. The scale of the maps may cause narrow coastal ranges or ranges on small islands not to appear. Not all vagrant or small disjunct occurrences are depicted. For migratory birds, some individuals occur outside of the passage migrant range depicted. For information on how to obtain shapefiles of species ranges see our Species Mapping pages at www.natureserve.org/conservation-tools/data-maps-tools.

Range Map Compilers: NatureServe 2008


U.S. Distribution by County Help
State County Name (FIPS Code)
FL Collier (12021), Glades (12043), Miami-Dade (12086), Monroe (12087)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
03 Western Okeechobee Inflow (03090103)+, Everglades (03090202)+, Florida Bay-Florida Keys (03090203)+, Big Cypress Swamp (03090204)+, Florida Southeast Coast (03090206)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
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Basic Description: A large crocodilian (American crocodile, Crocodylidae).
Reproduction Comments: Eggs are laid in April-May in Florida, Mexico, Venezuela, and Honduras; December-February in Ecuador and Panama (Kushlan and Mazzotti 1989); mid-February to early April in Dominican Republic (Fitch 1985); late March-early May in Belize (Platt and Thorbjarnarson 2000). Clutch size is 20-80 (average 38 in Florida, 24 in Hispaniola, 22 in Belize). Incubation averages about 85 days in Florida; female guards nest; eggs hatch in July and August. Hatching occurs April-June in West Indies (Schwartz and Henderson 1991), late June to mid-July in Belize (Platt and Thorbjarnarson 2000). Adult opens nest and may carry hatchlings to water. Parent apparently protects young for unknown duration. Females become sexually mature at an age of around 10-13 years. Clutches are laid singly or communally in southern Florida (Kushlan and Mazzotti 1989).
Ecology Comments: In Florida, most nest failures are due to raccoon predation and failure of eggs to hatch (USFWS 1980). Crocodiles in Florida have large (86-262 hectares) overlapping activity areas (Kushlan and Mazzotti 1989).
Habitat Type: Freshwater
Non-Migrant: N
Locally Migrant: Y
Long Distance Migrant: N
Mobility and Migration Comments: Crocodiles may make seasonal movements between freshwater and saline habitats (Gaby et al. 1985).
Marine Habitat(s): Near shore
Estuarine Habitat(s): Bay/sound, Forested wetland, Herbaceous wetland, Lagoon, River mouth/tidal river, Scrub-shrub wetland, Tidal flat/shore
Riverine Habitat(s): CREEK, Low gradient, MEDIUM RIVER
Lacustrine Habitat(s): Shallow water
Palustrine Habitat(s): Riparian
Terrestrial Habitat(s): Sand/dune
Special Habitat Factors: Burrowing in or using soil, Fallen log/debris
Habitat Comments: Habitat includes coastal mangrove swamps, brackish and salt water bays, lagoons, marshes, tidal rivers, brackish creeks; also abandoned coastal canals and borrow pits. Individuals may wander widely in coastal waters and may range inland into lakes and lower reaches of large rivers. American crocodiles occupy mostly nonsaline waters in the nonbreeding season, move to saline waters when breeding. In Florida, primary habitat is inland mangrove swamps protected from wave action; females use open waters of Florida Bay only for access to nesting sites (Kushlan and Mazzotti 1989).

Eggs are laid in a mounded nest of soil, sand, or peat, or in a hole in the ground (Kushlan and Mazzoti 1989). Florida Bay nest sites usually are at edge of hardwood thickets on small sand beaches, or on high marl banks of coastal creeks, or in mangrove swamps along old canal banks; also on berms of power plant cooling canal systems (Gaby et al. 1985). In the West Indies, nests most often are in the ecotone between Conocarpus-dominated riparian strip and xeric uplands (Schwartz and Henderson 1991). In Belize, most nesting areas were on elevated beach ridges of coarse sand; adjacent shallow brackish lagoons provided critical nursery habitat (Platt and Thorbjarnarson 2000). See also Lutz and Dunbar-Cooper (1984).

In Florida, shortly after hatching, hatchlings disperse from nest sites to nursery habitats that are generally more sheltered, have lower salinity (1-20 parts per thousand), shallower water (generally), and more vegetation cover (USFWS 2007). Lazell (1989) reported that young generally occupy brackish water but seem to do well in full salt water on North Key Largo (Florida), perhaps due to the effect of abundant rainfall.

Adult Food Habits: Carnivore, Invertivore, Piscivore
Immature Food Habits: Carnivore, Invertivore, Piscivore
Food Comments: Adults are believed to eat primarily fishes (USFWS 1980) but probably also eat large invertebrates and various vertebrates (mammals, birds, turtles). Young feed mainly on aquatic invertebrates (USFWS 1980, Platt et al. 2002).
Adult Phenology: Circadian
Immature Phenology: Circadian
Length: 460 centimeters
Economic Attributes
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Economic Comments: See Thorbjarnarson (1999) for a discussion of the limits to sustainable use of crocodilians.
Management Summary
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Management Requirements: The public should be educated about crocodiles. In Florida, efforts should be made to decrease accidental mortality and restore the natural hydrology of the Everglades. See USFWS (1998) for specific information on recovery and management in Florida.
Monitoring Requirements: EOs should be monitored. See Mazzotti and Brandt (1988) for live-trapping method. See Jones and Hayes-Odum (1994, Herpetol. Rev. 25:14-15) for a method for the restraint and transport of crocodilians.
Management Research Needs: Determine habitat requirements. Research methods of captive breeding and restocking.
Population/Occurrence Delineation
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Use Class: Not applicable
Minimum Criteria for an Occurrence: Occurrences are based on evidence of historical presence, or current and likely recurring presence, at a given location. Such evidence minimally includes collection or reliable observation and documentation of one or more individuals (including eggs) in or near appropriate habitat where the species is presumed to be established and breeding.
Separation Barriers: Busy highway or highway with obstructions such that alligators rarely if ever cross successfully (does not include highways that traverse continuous aquatic/wetland habitat); untraversable topography (e.g., cliff); urbanized area dominated by buildings and pavement and lacking aquatic or wetland habitat.
Separation Distance for Unsuitable Habitat: 1 km
Separation Distance for Suitable Habitat: 30 km
Separation Justification: Crocodiles in Florida have large (86-262 ha) activity areas (Kushlan and Mazzotti 1989). A 262-ha home range (if circular) would be about 1.8 km in diameter, but home rnages mapped by Kushlan and Mazzotti were elongate and up to approximately 15 km long. The separation distance of 30 km for suitable (aquatic/wetland) habitat is about twice this approximately 15-km home range length.
For the purposes of these occurrence specifications, unsuitable habitat refers to upland habitat. Movements across upland habitats are highly restricted under normal circumstances, so the nominal minimum separation distance of 1 km is used.

Inferred Minimum Extent of Habitat Use (when actual extent is unknown): 5 km
Date: 08May2001
Author: Hammerson, G.
Population/Occurrence Viability
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U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
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Authors/Contributors
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NatureServe Conservation Status Factors Edition Date: 19Feb2014
NatureServe Conservation Status Factors Author: Hammerson, G., and D. R. Jackson
Element Ecology & Life History Edition Date: 12Feb2009
Element Ecology & Life History Author(s): Hammerson, G.

Zoological data developed by NatureServe and its network of natural heritage programs (see Local Programs) and other contributors and cooperators (see Sources).

References
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  • Brisbin, I. L., Jr., and M. A. McDonald. 1989. Genetic patterns and the conservation of crocodilians: a review of strategies and options. Pages 156-168 in Crocodiles: Proc. 8th Working Meeting of the Crocodile Specialist Group, IUCN.

  • CONANT, R., AND J.T. COLLINS. 1991. A FIELD GUIDE TO REPTILES AND AMPHIBIANS, EASTERN AND CENTRAL NORTH AMERICA, THIRD ED. HOUGHTON MIFFLIN COMPANY, BOSTON, MASSACHUSETTS. 450 PP.

  • Conant, R. and J. T. Collins. 1991. A field guide to reptiles and amphibians: eastern and central North America. Third edition. Houghton Mifflin Co., Boston, Massachusetts. 450 pp.

  • Densmore, L. D., III, and P. S. White. 1991. The systematics and evolution of the Crocodilia as suggested by restriction endonuclease analysis of mitochondrial and nuclear ribosomal DNA. Copeia 1991:602-615.

  • Ernst, C. H., F. D. Ross, and C. A. Ross. 1999. CROCODYLUS ACUTUS. Catalogue of American Amphibians and Reptiles 700:1-17.

  • Fitch, H. S. 1985. Variation in clutch and litter size in New World reptiles. Univ. Kansas Museum Natural History, Miscellaneous Publication No. 76:1-76.

  • Gaby, R., M. D. McMahon, F. J. Mazzotti, W. N. Gillies, and J. R. Wilcox. 1985. Ecology of a population of CROCODYLUS ACUTUS at a power plant site in Florida. Journal of Herpetology 19:189-98.

  • Grant, C. 1940. The reptiles. Pages 61-148 in W. G. Lynn and C. Grant. The herpetology of Jamaica. Bull. Inst. Jamaica, Sci. Ser. No. 1.

  • International Union for Conservation of Nature and Natural Resources (IUCN). 1982a. Crocodiles. Proceedings of the 5th working meeting of the Crocodile Specialist Group of the Species Survival Commission. Gainesville, Florida, 12-16 August 1980.

  • Johnson, T. H. 1988. Biodiversity and conservation in the Caribbean. Profiles of selected islands. ICBP Monograph No. 1.

  • Kaiser, H., E.J.R. Sihotang, K. M. Marson, K. M. Crane, J. Dayov, and L. L. Grismer. 2001. A breeding population of American crocodiles, Crocodylus acutus, on Roatan, Islas de la Bahia, Honduras. Herpetological Review 32:164-165.

  • King, F. W., and R. L. Burke, editors. 1989. Crocodilian, tuatara, and turtle species of the world: a taxonomic and geographic reference. Association of Systematics Collections, Washington, D.C. 216 pp.

  • Krysko, K. L., K. M. Enge, and P. E. Moler. 2011. Atlas of amphibians and reptiles in Florida. Final report to Florida Fish and Wildlife Conservation Commission, Tallahassee, Florida. Submitted 15 December 2011.

  • Kushlan, J. A., and F. J. Mazzotti. 1989a. Historic and present distribution of the American crocodile in Florida. Journal of Herpetology 23:1-7.

  • Kushlan, J. A., and F. J. Mazzotti. 1989b. Population biology of the American crocodile. Journal of Herpetology 23:7-21.

  • Lazell, J. D., Jr. 1989. Wildlife of the Florida Keys: a natural history. Island Press, Washington, D.C.

  • LeBuff, C.  2014.  America's crocodile kings with notes on range, temperature tolerance, and nesting of Crocodylus acutus in southwest Florida.  Herpetological Review 45(4):643-649.

  • Lutz, P. L., and A. Dunbar-Cooper. 1984. The nest environment of the American crocodile (CROCODYLUS ACUTUS). Copeia 1984:153-61.

  • Luxmoore, R. A., et al., compilers. 1985. A directory of crocodilian farming operations. Jointly published by IUCN and CITES, Univ. Press, Cambridge, England. 204 pp.

  • Matthews, J.R. and C.J. Moseley (eds.). 1990. The Official World Wildlife Fund Guide to Endangered Species of North America. Volume 1. Plants, Mammals. xxiii + pp 1-560 + 33 pp. appendix + 6 pp. glossary + 16 pp. index. Volume 2. Birds, Reptiles, Amphibians, Fishes, Mussels, Crustaceans, Snails, Insects, and Arachnids. xiii + pp. 561-1180. Beacham Publications, Inc., Washington, D.C.

  • Mazzoti, F. J., L. A. Brandt, P. Moler, and M. S. Cherkiss. 2007. American crocodile (Crocodylus acutus) in Florida: recommendations for endangered species recovery and ecosystem restoration. Journal of Herpetology 41:122-132.

  • Mazzotti, F. J., and L. A. Brandt. 1988. A method of live-trapping wary crocodiles. Herpetol. Rev. 19:40-41.

  • McCann, F., A. H. Escobedo-Galván, and F. G. Cupul-Magaña.  2016.  Crocodylus acutus (American Crocodile).  Anthropogenic nesting.  Herpetologica Review 47:456-457.
     

  • Menzies, R. A., and J. A. Kushlan. 1991. Genetic variation in populations of the American crocodile. J. Herpetology 25:357-361.

  • Milián-García, Y., M. Venegas-Anaya, R. Frias-Soler, A. J. Crawford, R. Ramos-Targarona, R. Rodríguez-Soberón, M. Alonso-Tabet, J. Thorbjarnarson, O. I. Sanjur, G. Espinosa-López, and E. Bermingham. 2011. Evolutionary history of Cuban crocodiles Crocodylus rhombifer and Crocodylus acutus inferred from multilocus markers. Journal of Experimental Zoology 315:358-375.

  • Ogden, J. C. 1978. Status and nesting biology of the American crocodile, Crocodylus acutus, (Reptilia, Crocodili-dae) in Florida. J. Herpetology 12:183-196.

  • Platt , S. G., J. B. Thorbjarnarson, T. R. Rainwater , and D. R. Martin. 2013. Diet of the American Crocodile (Crocodylus acutus) in Marine Environments of Coastal Belize. Journal of Herpetology 47(1):1-10.

  • Platt, S. G., T. R. Rainwater, and J. B. Thorbjarnarson. 2002. Crocodylus acutus: hatchling diet. Herpetological Review 33:202-203.

  • Platt, S. G., and J. B. Thorbjarnarson. 2000. Nesting ecology of the American crocodile in the coastal zone of Belize. Copeia 2000:869-873.

  • Schubert, A. 1994. Conservation of American crocodile. Crocodile Specialist Group Newsletter 13(3):18.

  • Schwartz, A., and R. W. Henderson. 1988. West Indian amphibians and reptiles: a check-list. Milwaukee Pub. Mus., Contrib. Biological Geology No. 74:1-264.

  • Schwartz, A., and R. W. Henderson. 1991. Amphibians and Reptiles of the West Indies: Descriptions, Distributions, and Natural History. University of Florida Press, Gainesville, Florida. xvi + 720 pp.

  • Stabile, J.  2017.  Perspectives in conservation: an interview with Paul Moler.  Herpetological Review 48:378-380.

  • Thorbjarnarson, J. 1999. Crocodile tears and skins: international trade, economic constraints, and limits to the sustainable use of crocodilians. Conservation Biology 13:465-470.

  • Thorbjarnarson, J. B. 1988. The status and ecology of the American crocodile in Haiti. 86 pp.

  • Thorbjarnarson, J. B. 1996. Reproductive characteristics of the order Crocodylia. Herpetologica 52:8-24.

  • U.S. Fish and Wildlife Service (USFWS). 10 March 2007. Reclassification of the American crocodile distinct population segment in Florida from endangered to threatened. Federal Register 72(53):13027-13041.

  • U.S. Fish and Wildlife Service (USFWS). 1980. Selected vertebrate endangered species of the seacoast of the United States--the American crocodile. FWS/OBS-80/01.47.

  • U.S. Fish and Wildlife Service (USFWS). 1990. Endangered and threatened species recovery program: report to Congress. 406 pp.

  • U.S. Fish and Wildlife Service (USFWS). 1998. Multi-species recovery plan for the threatened and endangered species of South Florida. Technical/Agency draft, U.S. Fish and Wildlife Service, Atlanta, Georgia.

  • Webb, G. J. W., et al., eds. 1987. Wildlife management: crocodiles and alligators. Surrey Beatty & Sons Pty Limited, New South Wales, Australia. 552 pp.

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