Rhabdophis tigrinus
Silhouette: V. Deepak · PhyloPic
In 3 days ~10% in a week ~30%
Rhabdophis tigrinus, also known commonly as the tiger keelback, yamakagashi, or kkotbaem, is a species of venomous snake in the subfamily Natricinae of the family Colubridae. The species is native to East Asia and Southeast Asia. Many sources, though not ITIS, recognize one subspecies, Rhabdophis tigrinus formosanus of Taiwan.
The dorsal color pattern of R. tigrinus is olive-drab green, with black and bright orange crossbars or spots from the neck down the first third of the body. The belly is whitish. The average total length (including tail) is usually 60–100 cm (24–39 in).
R. tigrinus is found in eastern Russia (Primorskiy and Khabarovsk territories), North and South Korea, China (widespread, except in the western third and the extreme south; Zhejiang, Fujian, Jiangxi, Hubei, Guizhou, Sichuan, Gansu, Shaanxi and Inner Mongolia), on the island of Taiwan, in Vietnam and in Japan (Yakushima, Tanegashima, Kyūshū, Shikoku, Honshu, Osaka and in the Ryukyu Islands). The type locality given is "Japan".
The diet of R. tigrinus consists mainly of small vertebrates, especially frogs and toads. It forages using both chemical (smell/tongue... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Nikko National Park | 🇯🇵 Japan |
More parks will be added in future updates.
Rare
Under 5% of wildlife watchers report a Tiger Keelback sighting in Tokyo on a given day, based on 27 verified sightings from GBIF citizen-science data. It is the 10th most-seen of the 15 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.
April, August and November
In those months about 10% of wildlife watchers report a Tiger Keelback in Tokyo on a given day, against under 5% in May–July, September–October and December–March, the lowest months.
Between 5 and 8 am
Across all the parks we cover, that three-hour window holds the most Tiger Keelback sightings with a recorded time, and about 6 in 10 of them come between 6 am and 6 pm: it is most active around dawn and dusk.
4th of 4
Of the 4 cities where we can rate Tiger Keelback sightings, Tokyo ranks 4th at under 5%. The best odds are in Beijing (China, about 10%), Seoul (South Korea, about 10%) and Osaka (Japan, about 10%).
Same family: Colubridae
The closest relatives of the Tiger Keelback that you can see in Tokyo (family Colubridae, Colubrid Snakes) are Japanese Rat Snake (about 20%), Japanese Four-lined Ratsnake (about 10%) and Japanese Keelback (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Tiger Keelback is recorded against all the reptiles logged in Tokyo (27 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.
