PREVALENCE: Somewhat common
ACTIVE PERIOD: Active at night
KEY ID FEATURES: Olive green or brown body with faint black later stripe and yellow or tan lower side, small rounded head, 30-40 cm when mature
BEHAVIOR: Slow moving and very docile, not quick to bite or musk
SIZE: Small - 30-40cm
OTHER: Can be mistaken with other stream snakes but not easily confused with venomous species
QUICK ASSESSMENT 0-10
IMPORTANT: Many snakes have significant variance in coloration and pattern even within the same species. There can also be extreme differences in appearance from juveniles to adults so it is important to never assume you have properly identified a snake.
PHOTO CREDIT: Dan Rosenberg
Bicoloured Stream Snakes are olive green or brown with a faint black lateral strip and yellow or tan lower body coloration. They have a narrow head helpful for hunting between rocks in slow moving streams. Notrils and eyes evolved on top of the head due to their aquatic nature. Generally not exceeding 40-50 cm when mature.
Nocturnal, Bicoloured Stream Snakes come out at night to hunt fresh water shrimp, small fish and earth worms. They have also been observed out during heavy rain on trails hunting worms flushed out by water. Not quick to bite or squirm excessively they are not dangerous in anyway though it should be noted that all snakes are capable of biting.
Found largely in the New Territories at elevation around 100-400m the Bicoloured Stream Snake is not that common a snake to encounter in Hong Kong. Due to their diet of worms and fresh water prey they can be found most readily near rocky slow moving streams.
NO SNAKE SHOULD EVER BE HANDLED BY ANYONE BUT EXPERTS: Can be mistaken for some other stream snakes including the Anderson's and Striped Stream Snakes but generally not confused with venomous species.