Fordonia leucobalia
In 3 days ~10% in a week ~20%
Fordonia is a genus of aquatic snakes in the family Homalopsidae. It is monotypic, being represented by the single species Fordonia leucobalia, commonly known as crab-eating water snake and white-bellied mangrove snake. It is a common resident of mangrove swamps and tropical tidal wetlands from the coast of Southeast Asia to Indonesia and the coasts of Northern Australia.
Individual F. leucobalia reach up to a meter in length, and are brown or gray in color with a white belly. There is significant color variation. Some have spots. The anatomy reflects the snake's water-living lifestyle: the eyes are located atop the head, and the nostrils have valves that close when the snake dives.
The snake eats small prey that live in its habitat, such as frogs and small fish, and it specializes in crabs, hence its name. Like other homalopsines, F. leucobalia bears live young. Boulenger, George A. 1890 The Fauna of British India, Including Ceylon and Burma. Reptilia and Batrachia. Taylor & Francis, London, xviii, 541 pp.
Frith,C.B. & MacIver,D. 1978 The crab-eating Water Snake, Fordonia leucobalia (Schlegel), another snake new to Thailand. Nat. Hist. Bull. Siam Soc. (Bangkok) 27... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Singapore | 🇸🇬 Singapore |
Rare
Under 5% of wildlife watchers report a Crab-eating Snake sighting in Singapore on a given day, based on 18 verified sightings from GBIF citizen-science data. It is the 51st most-seen of the 64 reptiles we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
April
In that month about 10% of wildlife watchers report a Crab-eating Snake in Singapore on a given day, against under 5% in May to March, the lowest months.
Only Singapore, in our data
Singapore is the only city on Wallace's Line with enough records to rate Crab-eating Snake sightings: under 5% of wildlife watchers there report one on a given day.
GBIF citizen-science records
It is estimated from how often the Crab-eating Snake is recorded against all the reptiles logged in Singapore (18 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
