---
title: "What the sources say about the American Crocodile | AnimalTracks.wiki"
description: "58 claims from the American Crocodile profile, each beside the words of the source that backs it."
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# What the sources say about the American Crocodile (*Crocodylus acutus*)

> 58 claims from the American Crocodile profile, each beside the words of the source that backs it. A "..." marks a cut in a quote and [brackets] an insertion.

Profile: [American Crocodile](https://animaltracks.wiki/animals/american-crocodile/)

## Crocodylus acutus. Animal Diversity Web, University of Michigan.

https://animaldiversity.org/accounts/Crocodylus_acutus/

| The page says | The source says |
| :--- | :--- |
| Brackish estuaries | can also be found in brackish environments, such as example estuaries and swamps (note: stats.habitat; ADW wording, typos not ours) |
| Animal Diversity Web gives an average length of 3.5 meters. | Average length 3.5 m 11.48 ft |
| It also lives in freshwater rivers and lakes | They inhabit freshwater, including rivers, lakes and reservoirs |
| One population lives in a hypersaline lake in the Dominican Republic. | There is also a population in a unique hyper-saline lake in the Dominican Republic. |
| Jaws, stones and sunbathing | American crocodiles also ingest small stones to aid in grinding up their food. (note: heading) |
| A crocodile grabs prey in its powerful jaws and swallows it whole. | During hunting, prey is grabbed with their powerful jaws, swallowing it whole. |
| It also swallows small stones, which help grind up its food. | American crocodiles also ingest small stones to aid in grinding up their food. |
| Animal Diversity Web calls this gaping and says it helps regulate body temperature. | bask in the sun, open-mouthed, a behavior called "gaping." This regulates their body temperature. |
| Animal Diversity Web says a female lays 30 to 60 eggs in a hole or a mound | Female American crocodiles lay 30 to 60 eggs in a hole or a mount that take approximately 9 to 10 weeks to hatch. (note: FAQ 2; ADW prints 'mount') |
| they take about 9 to 10 weeks to hatch. | that take approximately 9 to 10 weeks to hatch (note: FAQ 2) |
| The female guards the nest for that whole stretch. | Females guard nests throughout that period. (note: FAQ 2) |
| dangerLevel: Deadly | American crocodiles have been known on the rare occasion to attack and kill or injure humans and domestic animals. (note: stats.dangerLevel; capability reading (#1273)) |

## AnAge entry for Crocodylus acutus. AnAge: The Animal Ageing and Longevity Database, Build 15, Human Ageing Genomic Resources.

https://genomics.senescence.info/species/entry.php?species=Crocodylus_acutus

| The page says | The source says |
| :--- | :--- |
| The AnAge ageing database lists an average adult weight of 76.7 kilograms. | Adult weight 76,700 g (note: listed under 'Life history traits (averages)'; 76,700 g = 76.7 kg. ADW's 2009 account (220-450 kg) was cut as the older figure) |
| A male in captivity lived at least 47 years and could have been 65 or older. | A male at least lived for at least 47 years but could have been 65 years or more (note: Maximum longevity 47 years (captivity)) |
| weightKg: 76.7 | Adult weight 76,700 g (note: battleStats.weightKg; AnAge life-history average) |

## American Crocodile (Crocodylus acutus). U.S. Fish and Wildlife Service.

https://www.fws.gov/species/american-crocodile-crocodylus-acutus

| The page says | The source says |
| :--- | :--- |
| a tapered snout | The crocodile's snout tapers forward from the eyes (note: tagline) |
| Fish, crabs, birds, turtles, snakes and small mammals | The adult crocodile's diet includes fish, crabs, birds, turtles, snakes, and small mammals. (note: stats.diet) |
| How big, how old | adults may grow to 4.5 meters or larger (note: heading) |
| Hatchlings are about 23 centimeters long. | Hatchlings are about 23 centimeters in length |
| Adults may grow to 4.5 meters or larger | adults may grow to 4.5 meters or larger |
| Adults eat fish, crabs, birds, turtles, snakes and small mammals. | The adult crocodile's diet includes fish, crabs, birds, turtles, snakes, and small mammals. |
| Young crocodiles feed chiefly on aquatic invertebrates and small fish. | The young feed chiefly on aquatic invertebrates and small fish. |
| Look at the snout and the teeth. The crocodile has a slimmer build and a snout that tapers forward from the eyes, while the alligator's snout stays rounded at the tip. | Florida crocodiles may be distinguished from alligators by their more slender build and their difference in snout shape. The crocodile's snout tapers forward from the eyes while the alligator's snout is untapered and rounded at the end. (note: FAQ 1) |
| With the mouth shut, the crocodile's fourth tooth in the lower jaw still shows. The alligator's is hidden. | When the mouth is closed, the fourth tooth in the lower jaw is exposed in the crocodile but concealed in the alligator. (note: FAQ 1) |

## American Crocodile, Crocodylus acutus. Florida Natural Areas Inventory, June 2001.

https://www.fnai.org/PDFs/FieldGuides/Crocodylus_acutus.pdf

| The page says | The source says |
| :--- | :--- |
| from southern Florida and the Greater Antilles through Mexico and Central and South America | Range - wide Distribution: Florida, Greater Antilles, Mexico, and Central and South America. (note: stats.habitat; Florida breeding populations are in southern Florida (same source)) |
| through the Greater Antilles, Mexico and Central America to northern South America | Range - wide Distribution: Florida, Greater Antilles, Mexico, and Central and South America. |
| Florida, its northern limit | Florida is the northern limit of the species' global range. |
| It often basks with its mouth open. | Often basks with mouth open. |

## Moller, Cherkiss & Mazzotti. The American Crocodile: A Story of Recovery. The Croc Docs.

http://crocdoc.ifas.ufl.edu/publications/posters/crocodilerecovery/

| The page says | The source says |
| :--- | :--- |
| Mostly brackish estuaries, creeks and mangrove swamps | The American crocodile inhabits brackish water and is typically found in ponds, coves, and creeks in mangrove swamps. (note: stats.habitat) |
| in Florida it is typically found in ponds, coves and creeks in mangrove swamps | is typically found in ponds, coves, and creeks in mangrove swamps (note: the poster is about Florida's crocodiles) |
| Florida's crocodiles were listed as endangered in 1975. | In 1975, Florida's crocodile population was listed as endangered by the US Fish and Wildlife Service. (note: FAQ 3; Florida's population) |
| In 2007 the US Fish and Wildlife Service moved them down to threatened, because the animals and their nests had become more widespread and more numerous. | In 2007, due to an increase in the distribution and number of crocodiles and nests, the US Fish and Wildlife Service downgraded their status in Florida to threatened. (note: FAQ 3) |

## Booth et al. (2023). Discovery of facultative parthenogenesis in a new world crocodile. Biology Letters.

https://doi.org/10.1098/rsbl.2023.0129

| The page says | The source says |
| :--- | :--- |
| A salt-tolerant crocodile with a tapered snout | saltwater tolerance, the species occurs from the southern U.S. (Florida) to Northern South (note: tagline; tapered snout is the next claim) |
| the first crocodilian with evidence of reproducing without a male | we provide, to our knowledge, the first evidence of FP in a crocodilian, the American crocodile, Crocodylus acutus (note: tagline; FP = facultative parthenogenesis, the paper's own term) |
| reproducing without a male | demonstrating a lack of paternal alleles (note: tagline) |
| Tolerates salt water | saltwater tolerance, the species occurs from the southern U.S. (Florida) to Northern South (note: stats.superpower) |
| Eggs with no father | demonstrating a lack of paternal alleles (note: heading) |
| In 2018, keepers at a park in Costa Rica found 14 eggs in the enclosure of an 18-year-old female American crocodile, Crocodylus acutus. | On 17 January ... 2018, a clutch of 14 eggs was discovered in the enclosure of an 18-year-old female American ... Crocodile housed on public exhibit at Parque Reptilandia, Costa Rica. |
| She was obtained at 2 years old and kept away from other crocodilians for her entire life. | when it was 2 years old (2002) and maintained in isolation from other crocodilians for its entire (note: preceded by 'This female was obtained' and followed by 'life', each across a manuscript line number) |
| Seven of the eggs looked fertile. | Of the 14 eggs laid, 7 appeared to be fertile and were artificially incubated. |
| After three months of incubation the eggs had failed to hatch | months of incubation the eggs had failed to hatch and were opened to assess their contents (note: preceded by 'After three' and a manuscript line number) |
| one held a fetus that could not have survived | nonviable fetus that upon dissection was determined via gross gonadal morphology as female (note: preceded by 'one egg was found to contain a fully-formed' and a manuscript line number) |
| Its DNA showed no contribution from a father. | demonstrating a lack of paternal alleles |
| The scientists reported the first evidence of facultative parthenogenesis in a crocodilian. | we provide, to our knowledge, the first evidence of FP in a crocodilian, the American crocodile, Crocodylus acutus (note: FP is defined as facultative parthenogenesis at the start of the abstract) |
| That unusual way of reproducing was already known in birds, lizards, snakes and elasmobranch fishes (sharks and rays). | This unusual reproductive mode has been documented in birds, non-avian reptiles-specifically lizards and snakes-and elasmobranch fishes |
| Unlike every vertebrate previously documented reproducing this way, crocodilians lack sex chromosomes. | unlike all previously documented cases of FP in vertebrates, crocodilians lack sex chromosomes and sex determination is controlled by temperature |
| Temperature controls whether an egg becomes a male or a female. | crocodilians lack sex chromosomes and sex determination is controlled by temperature |
| No sex chromosomes | crocodilians lack sex chromosomes (note: blockquote lead-in) |
| A coast dweller that handles salt | saltwater tolerance, the species occurs from the southern U.S. (Florida) to Northern South (note: heading) |
| Owing to its saltwater tolerance, the crocodile ranges from Florida | saltwater tolerance, the species occurs from the southern U.S. (Florida) to Northern South |
| kept away from other crocodilians for her entire life | maintained in isolation from other crocodilians for its entire (note: vibe.reason) |
| whose DNA showed no contribution from a father | demonstrating a lack of paternal alleles (note: vibe.reason) |
| the first evidence of facultative parthenogenesis in a crocodilian | the first evidence of FP in a crocodilian, the American crocodile, Crocodylus acutus (note: vibe.reason) |

## Briggs-Gonzalez et al. (2021). American crocodiles (Crocodylus acutus) as restoration bioindicators in the Florida Everglades. PLOS ONE.

https://doi.org/10.1371/journal.pone.0250510

| The page says | The source says |
| :--- | :--- |
| In a Florida capture study, the oldest crocodile recaptured was 22 years old. | the oldest recaptured crocodile was 22 years old |
| In South Florida 25 percent of hatchlings survive their first year, but survival climbs to nearly 90 percent by age six. | Estimated hatchling survival for the South Florida population was 25% increasing with ontogeny and reaching near 90% survival at year six (note: replaces Briggs-Gonzalez 2017's 16% with the 2021 estimate; 'first year' from 'After one year of age survival increases to 41%') |
| In a Florida study, crocodiles exposed to hypersaline water (above 40 on the salinity scale) in the dry season grew 13 percent slower after one year. | Crocodiles exposed to hypersaline conditions (> 40 psu) during the dry season maintained lower body condition scores and reduced growth rate by 13% after one year (note: psu = practical salinity unit, the paper's salinity scale) |

## Rainwater et al. (2022). Crocodylus acutus. The IUCN Red List of Threatened Species 2022: e.T5659A212805700.

https://doi.org/10.2305/iucn.uk.2022-1.rlts.t5659a212805700.en

| The page says | The source says |
| :--- | :--- |
| Vulnerable | IUCN Red List category: Vulnerable (VU). (note: stats.conservationStatus; GBIF copy of the Red List, taxon 5659) |
| The IUCN Red List rates the species Vulnerable. | IUCN Red List category: Vulnerable (VU). (note: body; GBIF copy of the Red List, taxon 5659) |