Venomous land snakes of HK part II From the daily HK wildlife blog: www.wildcreatureshongkong.org
Imi Bond reached out to touch the small cute black snake one evening on the Peak, but jumped back as it raised up its hood in a clear warning to not approach again. Whilst most people do not get that close to a deadly cobra, almost all of us who live, or walk, in the countryside have seen a snake, so how can we tell which snakes are safe and which are not? Pictured here HK's most "bitiest" snake, the bamboo pit viper, or White-lipped viper (Trimeresurus albolabris).
CAVEAT:- We cannot be responsible for readers’ inaccuracy of identifying snakes based on this guide. There are many variables that go into identifying a snake properly, and even experts can make mistakes. Do not use this guide to help you decide whether it is safe to touch or pick up a snake. Leave snakes alone, and stay outside of striking or spitting distance (3-5meters).
We have 52 different snake species in Hong Kong, and this article simply sets out to identify the most common dangerous and venomous snakes of HongKong in a step by step "easy" to identify guide. For part I of this 2 part series - including FAQs - please see yesterday's blog on www.wildcreatureshongkong.org How many kinds of venomous and deadly snakes are there in Hong Kong? Six land species can inflict life endangering bites:- the Banded Krait, the Many Banded Krait, Chinese Cobra, King Cobra, Coral Snake, and The Red-necked Keelback. The two other venomous snakes - both pit vipers, the Bamboo and Mountain Pit Viper - have bites that can cause extreme pain and swelling. Six other snakes have venom fangs at the back of the jaw, but are not known to produce much reaction in humans. The Common Rat Snake and the Burmese Python are not venomous, but do get very large, and their teeth can cause nasty cuts and gashes. (The mountain pit viper is extremely rare and secretive, so is not illustrated here).
Follow the questions 1,2,3 in BOLD to help with an ID of any deadly or dangerous native HK snake.
QUESTION 1. Is it (bright) green? There are two bright green snakes in Hong Kong; One is the venomous Bamboo Pit Viper (Trimeresurus albolabris), the other is the harmless Greater Green Snake (Cyclophiops major). Telling the difference: Head to head: Have a good look at the head and neck. (click on images for full size, or see Flickr page).
The Greater Green (on the left) has a more elongated head with much larger scales, and no neck. The Pit Viper has a triangular-shaped head with many small scales, a thin obvious neck, and orange-yellow or red eyes, with a slit (not round) pupil and they have a deep nasal pit. The other key distinguishing feature is the Pit viper has a reddish-brown streaked tail, see main photo above. The Bamboo Pit Viper is an aggressive snake, with a very painful bite, and is responsible for 90% of all recorded bites in Hong Kong (about 30 a year). Whilst the Greater Green is most active during the day the viper is primarily nocturnal and they end up biting people because they like to ambush their prey, so they do not normally move when they hear you, and rely on their camouflage to remain undisturbed; plus they can "see" and can strike at night using their heat sensing pit organs. QUESTION 2. Does it have a red neck?
If it does, then it is the venomous Red-Necked Keelback. (Rhabdophis subminiatus helleri)
Olive green with a red patch just behind the head, with yellow and black flecks throughout the body. The red marking can be quite faded in older adults. Not aggressive, but bites inflicted with the rear fangs – though rare - can be lethal. Often seen hunting frogs during the day.
Adults can secrete a toxic white substance from a groove in its neck making it unique in Hong Kong and rare as an animal that is both venomous (from its bite) and poisonous (if you eat it).
QUESTION 3. Does it have black bands around its body? Many snakes in HK appear to have bands, but the only strongly banded venomous ones are the deadly Kraits and the Coral Snake (the King Cobra is also banded, but not to the same contrast).
PICTURE ON LEFT: The many Banded Krait (Bungarus multicinctus multicinctus) Strongly banded in black and white, is quite common in Hong Kong, and likes to eat other snakes. This snake has an extremely toxic venom, which leads to respiratory paralysis and heart failure. I have often watched these snakes hunting, and they will often completely ignore your presence.
PICTURE ON RIGHT: There is also the very docile Banded Krait (Bungarus fasciatus) which are now rare due to loss of habitat. These easily recognisable alternating black and yellow banded snakes, whilst not aggressive, can also be fatal. You can also clearly see the triangular "ridge"type shape of the Kraits in this picture.
The many banded Krait can be confused with the harmless
Banded wolf snake or Mountain Wolf snake pictured on the left. The foremost world expert on Kraits was killed and died a horrible death due to this mistaken identity, so do not take any risks! Also the juvenile King cobra is strongly banded, yellow bands on black.
McClelland's Coral Snake (Sinomicrurus macclellandi) here on the right is another easily recognisable - but very rare - lethal snake in Hong Kong. Young are a much brighter red with thinner bands. below. It has a white band behind the eyes on the head. It was named in honour of or Dr John MacClelland a naturalist working for the East India Company. Photo credit: Dan Rosenberg.
QUESTION 4. Does it have a hood? Then it is a cobra. Either the common Chinese Cobra (Naja atra), or the rarer King Cobra (Ophiophagus hannah).
Pictures left to right: a)the hood from behind, clearly showing the "spectacles". b)A juvenile cobra in classic pose c)a cobra hunting, note the large head scales, but like this it is easily confused with a rat snake unless you look closely.
The Chinese cobra can be a big snake around one meter long, mostly black, but sometimes/rarely grey or gold in colour. A short, wide hood, usually with white eye spots, or “spectacles”. Active day and night. Venomous: Highly dangerous; bites may cause tissue necrosis and death. Comments: Will usually try to escape, but if confronted will raise its forebody, spread its hood, hiss, and strike readily. Some snakes have been known to spit venom so do not get too close with your phone to take a picture!
The rare King Cobra pictured below is lightly banded (juveniles strongly so, with yellow bands on black), and unlike the Chinese cobra it is without eye-shaped markings on the hood. Photo credit: Jean-Jacques Ferguson.
Mainly out during the day. Extremely dangerous. Can be black, grey, brown or even golden, with or without bands or spots.
Question 5. Is it a large dark coloured snake? Then it is probably either a deadly cobra OR a harmless ratsnake, and it is not always easy to tell them apart quickly and without a closer look, and both snakes can have different colourations and morphs from grey to black to golden. The rat snake has no hood, but this is not always easy to see. Perhaps the most distinctive feature is that the supralabial scales (ie the scales just along and under the eyes) have a black edge on the Common Rat snake seen here in the picture, and that “band” behind the eye often helps with an ID. The
Cobra also has large occipital scales - which means larger scales on top of its head.
Please do add your personal observations and comments.
Thank you to: Dan, Will, Kevin, Tommy and Abdel for being the bravest, and greatest, “snakers” I could ever hope to meet. Friends that got me into herping, and that have taught me so much. Also thank you to the Kadoorie Farm, and all its staff, for inspiration and all the good work they do for snakes and wildlife in Hong Kong.
For more updates about snakes and other wildlife in Hong Kong with stunning pictures and fascinating facts follow the daily blog at www.wildcreatureshongkong.org