Trimerodytes percarinatus
Silhouette: Alex Slavenko · PhyloPic
In 3 days ~10% in a week ~30%
Trimerodytes percarinatus, commonly known as the eastern water snake, olive keelback, olive annulate keelback or Chinese keelback water snake, is a species of snake in the subfamily Natricinae. The type locality for T. percarinatus is Guadun (formerly spelled as Kuatun), Wuyishan City (former Chongan County) in NW Fujian, China.
The subspecies Trimerodytes percarinatus suriki is endemic to Taiwan where it occurs in the whole country. T. percarinatus is a defensive snake that bites readily when caught, but it is not venomous. It is a medium-sized snake, typically attaining a total length (including tail) of 70–90 cm (28–35 in), but may grow up to 110 cm (43 in). An adult female usually lays 4 to 13 eggs, but may lay as many as 25 eggs.
T. percarinatus is found in NE India (Changlang District, Arunachal Pradesh), Myanmar (= Burma), Thailand, Laos, Vietnam, S China (Hainan, Zhejiang, Jiangxi, Fujian, Guangdong, Guangxi, Guizhou, Sichuan, Hubei), Hong Kong, and Taiwan. It is an aquatic species associated with hilly areas.
T. percarinatus preys on shrimps, frogs (including tadpoles), and fish. �... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Hong Kong | 🇨🇳 China |
Rare
Under 5% of wildlife watchers report a Mountain Water Snake sighting in Hong Kong on a given day, based on 11 verified sightings from GBIF citizen-science data. It is the 33rd most-seen of the 43 reptiles we can rate there. Over three days the chance rises to about 10%, and over a week to about 30%, if each day is a fresh chance.
May to October
In those months about 10% of wildlife watchers report a Mountain Water Snake in Hong Kong on a given day, against under 5% in November to April, the lowest months. Those are among Hong Kong's wettest months, with about 180 mm of rain a month against 25 mm in December.
Between 8 and 11 pm
Across all the parks we cover, that three-hour window holds the most Mountain Water Snake sightings with a recorded time, and about 7 in 10 of them come between 6 pm and 6 am: it is mostly seen at night.
Only Hong Kong, in our data
Hong Kong is the only city on Wallace's Line with enough records to rate Mountain Water Snake sightings: under 5% of wildlife watchers there report one on a given day.
Same family: Colubridae
The closest relatives of the Mountain Water Snake that you can see in Hong Kong (family Colubridae, Colubrid Snakes) are Common Wolf Snake (about 20%), Heller's Red-necked Keelback (about 10%) and Dhaman (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Mountain Water Snake is recorded against all the reptiles logged in Hong Kong (11 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.
