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What the sources say

American CrocodileCrocodylus acutus

Every figure, record and mechanism on the American Crocodile profile was written from a source, and this is the working table behind it: 58 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Animal Diversity Web, University of Michigan

Crocodylus acutus. Animal Diversity Web, University of Michigan.

The page saysBrackish estuaries
The source sayscan also be found in brackish environments, such as example estuaries and swampsNote: stats.habitat; ADW wording, typos not ours
The page saysAnimal Diversity Web gives an average length of 3.5 meters.
The source saysAverage length 3.5 m 11.48 ft
The page saysIt also lives in freshwater rivers and lakes
The source saysThey inhabit freshwater, including rivers, lakes and reservoirs
The page saysOne population lives in a hypersaline lake in the Dominican Republic.
The source saysThere is also a population in a unique hyper-saline lake in the Dominican Republic.
The page saysJaws, stones and sunbathing
The source saysAmerican crocodiles also ingest small stones to aid in grinding up their food.Note: heading
The page saysA crocodile grabs prey in its powerful jaws and swallows it whole.
The source saysDuring hunting, prey is grabbed with their powerful jaws, swallowing it whole.
The page saysIt also swallows small stones, which help grind up its food.
The source saysAmerican crocodiles also ingest small stones to aid in grinding up their food.
The page saysAnimal Diversity Web calls this gaping and says it helps regulate body temperature.
The source saysbask in the sun, open-mouthed, a behavior called "gaping." This regulates their body temperature.
The page saysAnimal Diversity Web says a female lays 30 to 60 eggs in a hole or a mound
The source saysFemale 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'
The page saysthey take about 9 to 10 weeks to hatch.
The source saysthat take approximately 9 to 10 weeks to hatchNote: FAQ 2
The page saysThe female guards the nest for that whole stretch.
The source saysFemales guard nests throughout that period.Note: FAQ 2
The page saysdangerLevel: Deadly
The source saysAmerican crocodiles have been known on the rare occasion to attack and kill or injure humans and domestic animals.Note: stats.dangerLevel; capability reading (#1273)

Source
02

AnAge: The Animal Ageing and Longevity Database, Build 15, Human Ageing Genomic Resources

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

The page saysThe AnAge ageing database lists an average adult weight of 76.7 kilograms.
The source saysAdult weight 76,700 gNote: 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
The page saysA male in captivity lived at least 47 years and could have been 65 or older.
The source saysA male at least lived for at least 47 years but could have been 65 years or moreNote: Maximum longevity 47 years (captivity)
The page saysweightKg: 76.7
The source saysAdult weight 76,700 gNote: battleStats.weightKg; AnAge life-history average

Source
03

U.S. Fish and Wildlife Service

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

The page saysa tapered snout
The source saysThe crocodile's snout tapers forward from the eyesNote: tagline
The page saysFish, crabs, birds, turtles, snakes and small mammals
The source saysThe adult crocodile's diet includes fish, crabs, birds, turtles, snakes, and small mammals.Note: stats.diet
The page saysHow big, how old
The source saysadults may grow to 4.5 meters or largerNote: heading
The page saysHatchlings are about 23 centimeters long.
The source saysHatchlings are about 23 centimeters in length
The page saysAdults may grow to 4.5 meters or larger
The source saysadults may grow to 4.5 meters or larger
The page saysAdults eat fish, crabs, birds, turtles, snakes and small mammals.
The source saysThe adult crocodile's diet includes fish, crabs, birds, turtles, snakes, and small mammals.
The page saysYoung crocodiles feed chiefly on aquatic invertebrates and small fish.
The source saysThe young feed chiefly on aquatic invertebrates and small fish.
The page saysLook 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.
The source saysFlorida 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
The page saysWith the mouth shut, the crocodile's fourth tooth in the lower jaw still shows. The alligator's is hidden.
The source saysWhen the mouth is closed, the fourth tooth in the lower jaw is exposed in the crocodile but concealed in the alligator.Note: FAQ 1

Source
04

Florida Natural Areas Inventory, June 2001

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

The page saysfrom southern Florida and the Greater Antilles through Mexico and Central and South America
The source saysRange - wide Distribution: Florida, Greater Antilles, Mexico, and Central and South America.Note: stats.habitat; Florida breeding populations are in southern Florida (same source)
The page saysthrough the Greater Antilles, Mexico and Central America to northern South America
The source saysRange - wide Distribution: Florida, Greater Antilles, Mexico, and Central and South America.
The page saysFlorida, its northern limit
The source saysFlorida is the northern limit of the species' global range.
The page saysIt often basks with its mouth open.
The source saysOften basks with mouth open.

Source
05

Moller, Cherkiss & Mazzotti

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

The page saysMostly brackish estuaries, creeks and mangrove swamps
The source saysThe American crocodile inhabits brackish water and is typically found in ponds, coves, and creeks in mangrove swamps.Note: stats.habitat
The page saysin Florida it is typically found in ponds, coves and creeks in mangrove swamps
The source saysis typically found in ponds, coves, and creeks in mangrove swampsNote: the poster is about Florida's crocodiles
The page saysFlorida's crocodiles were listed as endangered in 1975.
The source saysIn 1975, Florida's crocodile population was listed as endangered by the US Fish and Wildlife Service.Note: FAQ 3; Florida's population
The page saysIn 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.
The source saysIn 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

Source
06

Booth et al. 2023

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

The page saysA salt-tolerant crocodile with a tapered snout
The source sayssaltwater tolerance, the species occurs from the southern U.S. (Florida) to Northern SouthNote: tagline; tapered snout is the next claim
The page saysthe first crocodilian with evidence of reproducing without a male
The source sayswe provide, to our knowledge, the first evidence of FP in a crocodilian, the American crocodile, Crocodylus acutusNote: tagline; FP = facultative parthenogenesis, the paper's own term
The page saysreproducing without a male
The source saysdemonstrating a lack of paternal allelesNote: tagline
The page saysTolerates salt water
The source sayssaltwater tolerance, the species occurs from the southern U.S. (Florida) to Northern SouthNote: stats.superpower
The page saysEggs with no father
The source saysdemonstrating a lack of paternal allelesNote: heading
The page saysIn 2018, keepers at a park in Costa Rica found 14 eggs in the enclosure of an 18-year-old female American crocodile, Crocodylus acutus.
The source saysOn 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.
The page saysShe was obtained at 2 years old and kept away from other crocodilians for her entire life.
The source sayswhen it was 2 years old (2002) and maintained in isolation from other crocodilians for its entireNote: preceded by 'This female was obtained' and followed by 'life', each across a manuscript line number
The page saysSeven of the eggs looked fertile.
The source saysOf the 14 eggs laid, 7 appeared to be fertile and were artificially incubated.
The page saysAfter three months of incubation the eggs had failed to hatch
The source saysmonths of incubation the eggs had failed to hatch and were opened to assess their contentsNote: preceded by 'After three' and a manuscript line number
The page saysone held a fetus that could not have survived
The source saysnonviable fetus that upon dissection was determined via gross gonadal morphology as femaleNote: preceded by 'one egg was found to contain a fully-formed' and a manuscript line number
The page saysIts DNA showed no contribution from a father.
The source saysdemonstrating a lack of paternal alleles
The page saysThe scientists reported the first evidence of facultative parthenogenesis in a crocodilian.
The source sayswe provide, to our knowledge, the first evidence of FP in a crocodilian, the American crocodile, Crocodylus acutusNote: FP is defined as facultative parthenogenesis at the start of the abstract
The page saysThat unusual way of reproducing was already known in birds, lizards, snakes and elasmobranch fishes (sharks and rays).
The source saysThis unusual reproductive mode has been documented in birds, non-avian reptiles-specifically lizards and snakes-and elasmobranch fishes
The page saysUnlike every vertebrate previously documented reproducing this way, crocodilians lack sex chromosomes.
The source saysunlike all previously documented cases of FP in vertebrates, crocodilians lack sex chromosomes and sex determination is controlled by temperature
The page saysTemperature controls whether an egg becomes a male or a female.
The source sayscrocodilians lack sex chromosomes and sex determination is controlled by temperature
The page saysNo sex chromosomes
The source sayscrocodilians lack sex chromosomesNote: blockquote lead-in
The page saysA coast dweller that handles salt
The source sayssaltwater tolerance, the species occurs from the southern U.S. (Florida) to Northern SouthNote: heading
The page saysOwing to its saltwater tolerance, the crocodile ranges from Florida
The source sayssaltwater tolerance, the species occurs from the southern U.S. (Florida) to Northern South
The page sayskept away from other crocodilians for her entire life
The source saysmaintained in isolation from other crocodilians for its entireNote: vibe.reason
The page sayswhose DNA showed no contribution from a father
The source saysdemonstrating a lack of paternal allelesNote: vibe.reason
The page saysthe first evidence of facultative parthenogenesis in a crocodilian
The source saysthe first evidence of FP in a crocodilian, the American crocodile, Crocodylus acutusNote: vibe.reason

Source
07

Briggs-Gonzalez et al. 2021

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

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

Source
08

Rainwater et al. 2022

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

The page saysVulnerable
The source saysIUCN Red List category: Vulnerable (VU).Note: stats.conservationStatus; GBIF copy of the Red List, taxon 5659
The page saysThe IUCN Red List rates the species Vulnerable.
The source saysIUCN Red List category: Vulnerable (VU).Note: body; GBIF copy of the Red List, taxon 5659

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.