SUMMARY
VENOM: None
PREVALENCE: Very common
ACTIVE PERIOD: Most active during the day
KEY ID FEATURES: Bright green body with yellow belly, round pupil with long slender head
BEHAVIOR: Moderately fast with docile nature, not prone to bite, roosts in trees at night while hunting on ground during day
SIZE: Small/Medium - 1m+
IUCN: LC - Least Concerned
OTHER: Can be mistaken with Bamboo Viper
QUICK ASSESSMENT 0-10
GALLERY
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.
DESCRIPTION
With virtually no color variation all Greater Greens are bright green on top with yellow bellies. Not usually exceeding 1 meter in length, they have long slender bodies and long narrow heads with relatively large eyes and round pupils.
BEHAVIOR
Greater Green's are active during the day hunting various prey but largely consume earth worms necessarily meaning that they spend a lot of time on the ground. However, at night they commonly roost high up in trees or up in bushes or long grass in heavily vegetated areas. They are a docile snake when encountered but capable of quickly slithering away. Not prone to bite but they are capable of doing so as well as secreting a smelly musk on occasion. A bite from a Greater Green is completely harmless and may not even draw blood due to their small head size.
HABITAT
Found all over Hong Kong the Greater Green is one of the most common snakes to encounter in Hong Kong. Due to their diet of worms they can be found almost anywhere there is water, vegetation, soft ground and or leaf litter/rotting logs.
MISTAKEN IDENTITY
NO SNAKE SHOULD EVER BE HANDLED BY ANYONE BUT EXPERTS: One of the more unfortunate scenarios, the Greater Green is often mistaken for one of Hong Kong's other common species the White Lipped Viper aka The Bamboo Viper. As a result of this similarity Greater Green's are sometimes killed when encountered out of fear, despite their completely harmless nature. Key distinctions between the two are first their active period with Greater Green's out during the day and the Bamboo Viper at night, long slender head with round pupils on the Greater Green vs a bigger triangular head with vertical pupils on the Viper, propensity to flee of the Greater Green vs the Viper which will take a defensive 'S' position and usually hold it's ground, and at least in male Bamboo Vipers a distinct white line running from its upper lip down the length of its body, which is where the formal common name 'White-Lipped Viper' comes from. With that said, as with all snakes Greater Green's should never be handled by anyone other than experts due to its similarity to the Bamboo Viper, and any information provided here cannot garauntee accurate identification for the inexperienced.
GREATER GREEN vs BAMBOO VIPER
Key Differences: The Greater Green is longer and thinner relative to the Bamboo Viper in general, but the major differences are the head, scales, tail and active periods.
HEAD: the Greater Green has a long thin head that is only slightly distinguishable from its neck vs the Bamboo Viper which has a wide jaw that is much wider than its neck, especially when viewed from above. As a subset to differences in head shape the Greater Green has round pupils and the Bamboo Viper has vertical pupils but this is not a great means to distinguish the two as you would need to be very close and in certain light conditions the Bamboo Vipers pupils may appear almost round.
GREATER GREEN - Round pupils
BAMBOO VIPER - Vertical pupils
SCALES: The Greater Green has completely smooth sales that do not overlap vs the Bamboos Viper which has keeled scales that do overlap. A “keeled” scale is one that has a ridge down the middle and gives the scales a more rough matte appearance vs smooth scales which are relatively shiny. In addition, the Greater Green has large well defined head scales vs the Bamboo Viper which has tiny granulated scales. Finally Greater Green’s have green scales on top with yellow/green belly or “ventral” scales vs the Bamboo Vipers which have similar coloured belly scales but often also display a row of white scales down their sides just above the belly scales.
GREATER GREEN - Smooth scales
GREATER GREEN - Never a white stripe down the lower sides
BAMBOO VIPER - Keeled scales
BAMBOO VIPER - Sometimes a white stripe down the lower sides
TAIL: The Greater Green has a long green tail vs the Bamboo Viper which has an orange coloured tail.
GREATER GREEN - Green tail
BABOO VIPER - Orange tail
ACTIVE PERIODS: The Greater Green is a diurnal snake which means it is active during the day and sleeps in trees and bushes at night vs the Bamboo Viper which is nocturnal positioning low on slopes, fences, bushes and trees at night and normally hides during the day.