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What the sources say

Nile CrocodileCrocodylus niloticus

Every figure, record and mechanism on the Nile Crocodile profile was written from a source, and this is the working table behind it: 64 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

San Diego Zoo Wildlife Alliance Library 2026

Nile Crocodiles ( Crocodylus niloticus & C. suchus ) Fact Sheet: Summary. San Diego Zoo Wildlife Alliance Library, 2026.

The page saysFreshwater lakes, rivers and brackish coastal swamps in eastern and southern Africa and the Nile valley
The source saysSpecies: Crocodylus niloticus - Nile Crocodile (eastern Africa, Nile valley, southern Africa)Note: stats.habitat, range half
The page saysFreshwater lakes, rivers and brackish coastal swamps
The source saysHabitat: Freshwater lakes, rivers and brackish coastal swamps.Note: stats.habitat, habitat half
The page saysin eastern and southern Africa and the Nile valley
The source saysSpecies: Crocodylus niloticus - Nile Crocodile (eastern Africa, Nile valley, southern Africa)
The page sayslives in freshwater lakes, rivers and brackish coastal swamps
The source saysHabitat: Freshwater lakes, rivers and brackish coastal swamps.
The page saysCrocodiles of west and central Africa are a newly recognized separate species, Crocodylus suchus.
The source saysSpecies: Crocodylus suchus - Nile Crocodile (west and central Africa)Note: 'newly recognized' from the same page: 'Crocodylus suchus : Newly recognized species; assessment not yet available'
The page saysThe 2017 Red List assessment rated the Nile crocodile Least Concern.
The source saysCrocodylus niloticus : Least Concern (2017 assessment)
The page saysThe zoo fact sheet, which covers both Nile crocodile species together, estimates 250,000 to 500,000 wild individuals but says the figures are not reliable.
The source saysEstimated 250,000 to 500,000 individuals, but figures not reliable.
The page sayswhich covers both Nile crocodile species together
The source saysNile Crocodiles ( Crocodylus niloticus & C. suchus ) Fact Sheet: SummaryNote: faq 3 scope

Source
02

San Diego Zoo Wildlife Alliance Library 2026

Nile Crocodiles ( Crocodylus niloticus & C. suchus ) Fact Sheet: Physical Characteristics. San Diego Zoo Wildlife Alliance Library, 2026.

The page saystogether they are the largest crocodiles in Africa
The source saysLargest crocodile in AfricaNote: the fact sheet covers C. niloticus and C. suchus together, so the superlative is scoped to both
The page saysa total length of 2.0 to 3.3 m
The source saysTotal Length 2.0-3.3 m (6.6-11 ft)Note: two-species figure, scoped in the sentence ('For both')
The page saysa weight of 70 to 100 kg
The source saysWeight 70-100 kg (154-220 lb)Note: two-species figure; table column is 'Males & Females'
The page saysmales are larger than females
The source saysMales larger than females.
The page saysIts maximum recorded length, snout to tail tip, is 5 m
The source saysMaximum recorded body length from snout to tip of tail is 5 m (16 ft)
The page saysadults of 1,000 kg have been reported
The source saysAdults weighing 1,000 kg (2,205 lb) have been reported
The page saysAfrica's largest crocodiles
The source saysLargest crocodile in AfricaNote: heading; two-species scope
The page saysThe San Diego Zoo Wildlife Alliance fact sheet this page draws on covers both species together
The source saysNile Crocodiles ( Crocodylus niloticus & C. suchus ) Fact Sheet: Physical CharacteristicsNote: scope of every SDZWA page

Source
03

San Diego Zoo Wildlife Alliance Library 2026

Nile Crocodiles ( Crocodylus niloticus & C. suchus ) Fact Sheet: Behavior & Ecology. San Diego Zoo Wildlife Alliance Library, 2026.

The page saysAt the water surface, only its eyes, ears and nostrils are exposed.
The source saysAt the water surface, only the eyes, ears, and nostrils are exposed
The page saysOut of water it tires easily.
The source saysBecome exhausted easily on land
The page saysThe fastest way a crocodile moves on land is the gallop
The source saysGallop (from Webb and Manolis 1989; Cott 1975) Fastest form of terrestrial movement
The page sayswhich the fact sheet calls typical of the young of some crocodile species
The source saysTypical in the young of some crocodile species
The page saysA galloping crocodile reaches 18 km/h for short distances
The source saysReach speeds of 18 km/hr (11mi/hr) for short distances
The page saysit may stay under for up to two hours
The source saysMay remain underwater for up to two hours when not moving
The page saysIts blood is adapted to cope with lactic acid levels that would kill other vertebrates.
The source saysadapted to high levels of lactic acid in their blood ... Such lactic acid levels would kill other vertebrates

Source
04

San Diego Zoo Wildlife Alliance Library 2026

Nile Crocodiles ( Crocodylus niloticus & C. suchus ) Fact Sheet: Diet & Feeding. San Diego Zoo Wildlife Alliance Library, 2026.

The page saysMostly fish, plus mammals such as impala, buffalo and young hippos
The source saysFish are mainstay of dietNote: stats.diet
The page saysMostly fish, plus mammals such as impala, buffalo and young hippos
The source saysFeed on impala, bushbuck, water buck, giraffes, buffalo, young hippos, hyenas, wild dogs, porcupines, and lions in Kruger National ParkNote: stats.diet, mammals half
The page saysLaunches its body out of the water to grab prey
The source saysLaunch body out of the water to grab preyNote: stats.superpower
The page saysIt swims silently underwater until it is near the shore
The source saysSilently swim underwater until near shore
The page saysmay surface with its eyes above the water to check its position
The source saysMay surface, with eyes above the water, to check position
The page saysthen launches its body out of the water to grab prey
The source saysLaunch body out of the water to grab prey
The page saysIt can lunge several times its own body length onto land.
The source saysCan lunge several times own body length out of the water, onto land
The page saysIt drags prey into the water to drown it
The source saysDrag prey into water and drown
The page saystears big prey apart by holding on and rotating until a piece comes away
The source saysCrocodile takes hold of prey and rotates in the water until a piece is torn away
The page saysIts tail bats at birds in the reeds, bending the reeds down and flipping the birds into the water.
The source saysTail bats at birds in reeds Tail bends reeds down and flips birds into water
The page saysFish are the mainstay of an adult's diet
The source saysFish are mainstay of diet
The page saysin South Africa's Kruger National Park it also takes impala, buffalo, giraffes and young hippos
The source saysFeed on impala, bushbuck, water buck, giraffes, buffalo, young hippos, hyenas, wild dogs, porcupines, and lions in Kruger National Park
The page saysOne meal may be up to 20% of its body mass.
The source saysMay consume up to 20% of body mass in one meal
The page saysStones are often found in their stomachs and may make up about 1% of a crocodile's body weight.
The source saysGastroliths (rocks) often found in the stomach ... May account for c. 1% of total body weight
The page sayslists possible jobs: helping with buoyancy, giving stability in the water, and adding weight to help hold down struggling prey
The source saysTo help maintain buoyancy in the water Useful when lying on the river bottom Added weight helps to subdue struggling prey To lower the center of gravity and gain stability in the water
The page saysYoung crocodiles have no stones inside them.
The source saysYoung crocodiles lack gastroliths in the stomach

Source
05

San Diego Zoo Wildlife Alliance Library 2026

Nile Crocodiles ( Crocodylus niloticus & C. suchus ) Fact Sheet: Reproduction & Development. San Diego Zoo Wildlife Alliance Library, 2026.

The page saysEggs incubated at 28 to 31 °C hatch only females, while 34 °C produces 81% male hatchlings.
The source saysOnly females hatch at temperatures between 28°C and 31°C ( 82-88°F) (Hutton 1987) Male neonates Temperatures of 34°C (93°F) result in 81% male hatchlings
The page saysEggs incubated below 27 °C never hatch.
The source saysEggs incubated below 27°C (81°F) never hatch
The page saysNest temperature picks the sex
The source saysSex determined by nest temperatureNote: heading
The page saysThe mother digs a hole with her hind limbs and snout
The source saysFemale digs hole with hind limbs and snout
The page sayslays 55 to 60 eggs
The source saysClutch size 55-60 eggs
The page saysIncubation takes 84 to 90 days
The source saysEggs are incubated 84 to 90 days
The page saysshe guards the nest for about 10 to 14 weeks
The source saysWatches nest for c. 10-14 weeks
The page saysAt hatching, the young call from inside the eggs, and the sound can be heard up to 20 m away.
The source saysBaby crocodiles utter distress calls from within the egg below ground Sound can be heard up to 20 m
The page saysShe moves the soil off
The source saysFemale moves soil off the nest to allow young to escape
The page saysgathers hatchlings in her mouth and carries them to the water
The source saysgathers hatchlings in her mouth, and moves from nest to nearby water
The page saysA hatchling is about 28 cm long and weighs about 80 g.
The source saysBody measures c. 28 cm (11 in) long Weigh c. 80 g (2.8 oz)

Source
06

San Diego Zoo Wildlife Alliance Library 2026

Nile Crocodiles ( Crocodylus niloticus & C. suchus ) Fact Sheet: Distribution & Habitat. San Diego Zoo Wildlife Alliance Library, 2026.

The page saysbut not at Africa's southern tip
The source saysAbsent from the southern tip of Africa

Source
07

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

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

The page saysA wild-born female Nile crocodile was reported living more than 56 years in captivity.
The source saysA wild born female was reported living more than 56 years in captivity

Source
08

Leitch & Catania 2012

Leitch & Catania (2012). Structure, innervation and response properties of integumentary sensory organs in crocodilians. Journal of Experimental Biology.

The page saysAn armored crocodile whose skin is more touch-sensitive than a primate's fingertips
The source saysDespite crocodilians' armored bodies, the ISOs imparted a mechanical sensitivity exceeding that of primate fingertips.Note: tagline; the study covered the Nile crocodile and the American alligator
The page saysA Nile crocodile looks like a suit of armor
The source saysDespite crocodilians' armored bodiesNote: armored bodies
The page sayson a Nile crocodile's jaws and body scales
The source saysIntegumentary sensory organs (ISOs) are densely distributed on the jaws of crocodilians and on body scales of members of the families Crocodilidae and Gavialidae.Note: jaws and body scales
The page saysroughly 9,000 sensory organs
The source saysEach of the ISOs (roughly 4000 in A. mississippiensis and 9000 in C. niloticus)Note: count
The page saysIn tests on Nile crocodiles and American alligators, these organs were more sensitive to touch than primate fingertips.
The source saysdocumented related behaviors for an alligatorid (Alligator mississippiensis) and a crocodylid (Crocodylus niloticus)Note: species tested
The page saysthese organs were more sensitive to touch than primate fingertips
The source saysthe ISOs imparted a mechanical sensitivity exceeding that of primate fingertips
The page saysSome of their nerve units responded most strongly to vibrations of 20 to 35 hertz (cycles per second), which fits reports that the organs detect ripples made by prey on the water surface.
The source saysSeveral rapidly adapting units responded maximally to vibrations at 20-35 Hz, consistent with reports of the ISOs' role in detecting prey-generated water surface ripples.Note: units are the afferent nerve units recorded; hertz gloss: cycles per second, from the SDZWA behavior page, 'frequencies between 100 and 4,000 hertz (cycles per second)'; "most strongly" paraphrases "maximally"
The page saysThe researchers also concluded that the organs help indicate when to bite, based on direct contact with pursued prey.
The source saysWe conclude that crocodilian ISOs have diverse functions, including detection of water movements, indicating when to bite based on direct contact of pursued preyNote: 'crocodilian' scope in source
The page saysNerve units in a Nile crocodile's skin sensors respond most strongly to vibrations of 20 to 35 hertz
The source saysSeveral rapidly adapting units responded maximally to vibrations at 20-35 Hz, consistent with reports of the ISOs' role in detecting prey-generated water surface ripples.Note: vibe.reason; same quote as the body claim "Some of their nerve units responded most strongly to vibrati"
The page saysthe kind of ripples prey make on the water
The source saysSeveral rapidly adapting units responded maximally to vibrations at 20-35 Hz, consistent with reports of the ISOs' role in detecting prey-generated water surface ripples.Note: vibe.reason; same quote as the body claim "Some of their nerve units responded most strongly to vibrati"

Source
09

Turner & Marais 2017

Turner & Marais (2017). Crocodylus niloticus. The IUCN Red List of Threatened Species 2017: e.T45433088A203590190.

The page saysLeast Concern
The source saysIUCN Red List category: Least Concern (LC).Note: stats.conservationStatus; category read through GBIF's copy of the Red List for taxon 45433088

Source
10

Kavhu et al. 2025

Kavhu et al. (2025). Mapping human fatalities from megafauna to inform coexistence strategies. Scientific Reports.

The page saysdangerLevel: Deadly
The source saysFor crocodiles, the Sen’s slope estimate was 3.5, indicating an upward trend from 16 fatalities in 2016 to 37 in 2022Note: task #1009; Deadly is 'Capable of killing a human'. The study counts human fatalities in Zimbabwe, where the one crocodile is C. niloticus (the paper names it: 'we assess fatalities caused by six megafaunal species: Nile crocodile ( Crocodylus niloticus )'); C. suchus is west and central African

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.