Reptilia · Squamata
Fordonia leucobaliaSchlegel, 1837
Crab-eating (Water) Snake
Photograph by Robert Ham, CC BY-SA, via Wikimedia Commons
A water-living, nocturnal, meat-eating snake from the Australo-Pacific region, reaching 100 cm nose to tail.
Also called White-bellied mangrove snake.
Reptilia › Squamata › Homalopsidae › Fordonia
- Grows to
- 1000mm
- greatest recorded
- Eats
- Carnivorous
- Active
- Nocturnal
- Lives
- Aquatic
Longer than 84% of all species in Homalopsidae anyone has measured.
The bar is the rank itself: its length is the share of the family this animal exceeds. The chart below is the family’s real spread, on a logarithmic scale because body length here runs from 128 to 1,400 mm. The solid rule is this animal. Every bar is a count of real species, and nothing on this figure is estimated.
What is known
34 sourced facts, each taken from a named scientific dataset. How to read these.
Cited from a dataset unless a row is marked otherwise.
Standing in the world
- Still living
- Extant
- Conservation status
- Least Concern
- Status assessed · the year the Red List last looked
- 2017
The animal itself
- Limbs
- None
- Pupil
- Round
- Fangs
- At the back of the mouth
Size
- Length snout to vent · greatest recorded
- 705mm2 ft 4 in
- Length snout to vent · adult female mean
- 512mm20 in
- Length nose to tail · greatest recorded
- 1000mm3 ft 3 in
- Largest female · snout to vent
- 491mm19.5 in
- Largest male · snout to vent
- 512mm20 in
- Hatchling length · snout to vent
- 160mm6.25 in
- Body mass · greatestcomputed
- 666.8g1.5 lb
- Body mass at hatchingmeasured
- 6.9g0.24 oz
1000 mm total length (Feldman et al. 2016), Shine 1994 (37 males 38.6-65.9, mean 49.1 cm SVL; 38 females 35.5-70.5, mean 51.2 cm SVL; hatchling SVL 160 mm, see also Shine 1991), Cox et al. 2012 (males max 817, females max 764 mm; Malcolm smith reported a 940 mm female)
snakes only in this source
snout-vent length; the source column mixes this with straight carapace length
largely converted from length by allometry in the source
How it lives
- Diet
- Carnivorous
- Active
- Nocturnal
- Where it lives
- Aquatic
- Habitat
- Marine Neritic
- Biome
- Tropical & Subtropical Grasslands, Savannas & Shrublands
- Region
- Australo-Pacific
- Mainland or island
- Mainland
- Highest it lives · above sea level
- 10m
- Range size
- 964,296km²
100% insects (Shine 1994, n = 63 items), fish (Shine 1991)
Cogger 2018, Cox et al. 2012
(Cogger 2018), semi aquatic (Cox et al. 2012)
sea level (O'Shea 2018)
Breeding
- Reproduction
- Viviparous
- Average clutch
- 6.1eggs
- Eggs or young per clutch
- 2–17eggs
- Mean clutch
- 6.1eggs
Feldman et al. 2015, Cox et al. 2012
2-17 mean=6.1 s.d.=4.2 n=15 (Shine 1991), 2-17 n=15 mean=6.1, 3-5 mean=6.1,13, 2-11, 8 (Murphy 2007), 6-15 (Whitaker and Captain 2004, O'Shea 2018), Shine 1994 (2-17, mean 6.1, n = 15 clutches)
Naming and history
- Suborder
- Serpentes
- Infraorder
- Alethinophidia
- Subspecies
- No
- Described by
- Schlegel
- Moved to another genus · since it was first described
- Yes
- Described in
- 1837
- Type locality
- Australia
Keeping one
3 ft 3 in × 19.5 in × 2 ft 6 in(100 × 50 × 75 cm)
Minimum length × width × height, for one animal. Bigger is always better.
The standard sizes snakes as a fraction of total length: 1 × 0.5 × 0.75.
Spends time in water, so a water area is part of the enclosure rather than a dish.
Mindestanforderungen an die Haltung von Reptilien (Sachverständigengutachten), German Federal Ministry for Nutrition, Agriculture and Forestry, Animal Welfare Division, 10 January 1997. The standard states these floor areas are recommendations rather than binding limits.
From this animal’s own total length of 3 ft 3 in (1000 mm), at 1 × 0.5 × 0.75 times it, following the German federal welfare standard — how this is worked out.
No preferred body temperature has been recorded for Crab-eating (Water) Snake. Rather than repeat a number from a care sheet, this page leaves it out.
Feeding
A prey item should be between the same width as the widest part of the snake's body and about 1.5 times that width.
Widely used across snake husbandry references. An alternative formulation gives prey at 10-15% of the snake's body mass. This is established practice, not a measurement.
64kJ per day
Worked out for an animal of 667 g, the heaviest recorded for Crab-eating (Water) Snake — so it is the top of the range, not a figure for a particular animal. Weigh yours and the number will be lower.
An upper estimate, not a feeding target, and not veterinary advice. The equation covers only what an animal burns staying alive, so a growing, gravid or recovering animal needs more — and it was measured on wild animals, which move far more than one in an enclosure. Body condition and a vet who knows the species are what a feeding decision should rest on. Where this comes from.
What nobody knows
These are not gaps in our research. No scientific dataset records them for this species — and saying so is information you cannot get from a reference that simply leaves a field out.
- — Length snout to vent · adult male mean
- — Length snout to vent · adult mean
- — Female length · mean, nose to tail
- — Length nose to tail · adult male mean
- — Length nose to tail · adult mean
- — Largest female · shell length
- — Largest male · shell length
- — Hatchling length · nose to tail
- — Largest juvenile · snout to vent
- — Largest juvenile · shell length
- — Egg length
- — Egg width
- — Body mass · a typical adult
- — Body mass · adult female, mean
- — Longest recorded life
- — Preferred body temperature · chosen in a laboratory gradient
- — Body temperature when active · measured in the wild
- — Eats arthropods
- — Eats vertebrates
- — Eats plant matter
- — How it hunts
- — How the young develop
- — Gestation or incubation
- — Clutches in a year
- — Clutches a year · fewest
- — Clutches a year · most
- — First breeds from · youngest recorded
- — First breeds by · oldest recorded
- — Hatchling length · smallest recorded
- — Hatchling length · largest recorded
- — Age at first breeding · female
- — Mature from · youngest recorded
- — Mature by · oldest recorded
- — Size at maturity · smallest recorded
- — Size at maturity · largest recorded
- — Venomous
- — Body temp in the wild · lowest mean recorded
- — Body temp in the wild · highest mean recorded
- — Colour on the back
- — Pattern on the back
- — Sex decided by
- — Population trend
- — Red List criteria
- — Active season · shortest recorded
- — Active season · longest recorded
- — Density · lowest recorded
- — Density · highest recorded
- — Home range · largest recorded
- — Active in
- — Lowest it lives · above sea level
Others in Homalopsidae
Take this data
Everything on this page is available as data under CC BY 4.0 — use it freely, credit it, no permission needed.
This species as JSON · the whole dataset
Cite this page
The Reptile & Amphibian Encyclopedia (2026). Fordonia leucobalia. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/fordonia-leucobalia
@misc{fordonia_leucobalia_2026,
title = {Fordonia leucobalia},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/fordonia-leucobalia}
}Sources
- Meiri, S. (2024). SquamBase — a database of squamate (Reptilia: Squamata) traits. Global Ecology and Biogeography. Public domain (CC0).
- Oskyrko, O. et al. (2024). ReptTraits: a comprehensive dataset of ecological traits in reptiles. Scientific Data. Used under CC BY 4.0.
- Catalogue of Life (dataset 3LR), used under CC BY.