We chose venomous snakes for this April (Earth Day) blog as they are out and about now in spring/summer, along with other poikilothermic, ectothermic tetrapods, or cold blooded creatures that love the sun. This is not an exhaustive science based field guide (there are no source references). We are keen and enthusiastic naturalists, focused on Hong Kong wildlife with my camera. Do sign up for future twice monthly wildlife information and photos. Simply e-mail firstname.lastname@example.org to be added (no-spam). For a fuller PDF guide please see the download link at the article end.
Hong Kong has a recorded 52 species of snake. Six land species can inflict life endangering bites (the Banded Krait, the Many Banded Krait, Chinese Cobra, King Cobra, and Coral Snake). These "elapid" snake bites cause nerve related, necrosis and tissue damage. The Red-necked Keelback is a rear fanged colubrid. The two other venomous snakes - both pit vipers, the Bamboo and Mountain Pit Viper - have bites that can cause extreme pain and swelling (and still pose a fatality threat to children and dogs). Six other snakes have enlarged venom fangs at the back of the jaw (opistholglyphous), 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 other lethal snakes not listed here, as they are so uncommon, are The Tonkin and Pointed Scale Pit Vipers, and any of the sea snakes.
Disclaimer: Great care was taken to ensure the information in this guide is accurate, but mistakes happen. If you find something inaccurate, please write to me at email@example.com
For a comprehensive guide of all Hong Kong snakes (not just venomous) please go to:- https://www.flickr.com/groups/ark_hongkong_reptiles/ and scroll down and click the links. 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).
SNAKE ID Follow the questions in red to snakes to help with an ID. There is NO easy way to tell venomous from non-venomous snakes, unless you actually know the snakes...and even then ID is not always clear in the heat of the moment. (Can you really tell that the third supralabial scale is NOT touching the eye and nasal scale? be honest). So basic principles apply...leave them alone, and they WILL leave you alone. You will not be attacked by a snake - why would it? it cannot eat you! In Hong Kong all snakebites on humans are defensive. If you really want to learn more about snakes, then please sign up for a night-time herp tour.
1. Is it (bright) green? Often confused and mistaken for each other, it’s either the a)Venomous Pit Viper, or the harmless b)Greater Green.
a) the Bamboo Pit Viper – Trimeresurus albolabris.
Venomous: Extremely painful bite. Responsible for 95% of all bites in Hong Kong (about 30-50 a year), but no recorded fatalities. Very common. Primarily nocturnal. One of the few snakes that will not move away immediately.
Key differentiating features:. Triangular-shaped head with many small scales; thin obvious neck; orange-yellow or red eyes, with slit (not round) pupil; reddish-brown streaked tail. There is also a deep nasal pit. The Pit Vipers 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
The Pit Vipers are nocturnal, so if you see a green snake during the day it is more than likely the harmless and inoffensive I.ii Greater Green Snake.Cyclophiops major. Non-Venomous. Key differentiating features:. Elongated head with large scales and no neck: Grey, golden or light brownish eyes, with large black pupil; very likely to move rapidly away from any encounter.
2. Does it have a red neck? Then it is the Red-Necked Keelback. Rhabdophis subminiatus helleri Olive green with a red patch just behind the head, with yellow and black flecks throughout the body. red marking can be quite faded in older adults.
Venomous and poisonous: Not aggressive, most human bites involve a nip with the front teeth but bites inflicted with the rear fangs – though rare - can be lethal. Often seen hunting frogs during the day.
Comments: Juveniles are particularly attractive. Adults can secrete a toxic white substance from a groove in its neck making it unique as a venomous and poisonous snake.
3. Does it have black and white or black and yellow bands/stripes? 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).
Many Banded KraitBungarus multicinctus multicinctus
Venomous: Extremely toxic. The venom can lead to respiratory paralysis and heart failure. Bites readily if picked up, and has a flexible neck that can twist and bite. Comments: there is also a Banded Krait Bungarus fasciatus which are rare due to loss of habitat. These large alternating black and yellow banded snakes, whilst not aggressive, can also be fatal.
The Coral Snake Calliophis macclellandi. below. If it has thin black stripes on a reddish brown body, with a white band behind the eyes on the head. Highly venomous, but rare, and not aggressive.
4. Does it have a hood? Then it is a cobra. Either the common Chinese Cobra, or the rare King Cobra.
Chinese CobraNaja atra
Appearance: A heavy bodied snake, 90-130cm, mainly 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.
Here seen hunting, wthout the hood raised. You can see the large scales on top of its head.
Below, the rare King Cobra, Ophiophagus hannah, is 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 and fatalities have been recorded in Hong Kong. Can be black, grey, brown or even golden! with or without bands or spots. Mainly out during the day. Extremely dangerous and fatalities have been recorded in Hong Kong. Can be black, grey, brown or even golden! with or without bands or spots.
5. Is it mottled/spotted? With rows of alternating dark spots.
Then it is the Large Spotted Cat Snake Boiga multomaculata Very long and slender, with a distinct triangular head. Aboreal and often found in trees and bushes. Mildly venomous, and not dangerous, but bites readily.
6. Is it in the water? Not the only snakes you will see in the water, all snakes are good swimmers, but these snakes rarely leave it, although sometimes coming onto land on rainy nights to hunt for frogs.
The Plumbeous water snake Enhydris plumbea below is very small and only mildly venomous.
The Chinese water snake Enhydris chinensis below is quite stout with an orange stripe on its lower flank. Only mildly venomous.
7. What other Venomous snake could it be? The mock viper- Psammodynastes pulverulentus.
Mildly venomous with rear fangs, with no documented record of local snakebite. Often out during the day. I have found these in many different colours, dark brown, grey, red/orange, almost white on occasion. They look aggressive, but also have a defence of playing dead very realistically, with tongue out and body contorted. Made us jump when we picked one up, so be careful.
8. What other venomous snakes are not covered here? Sea Snakes - highly venomous, but very rare. Mangrove Water Snake. Rare, only in deep bay and Tai O, and only mildly venomous. The Tonkin, the Point Scaled, and the Mountain Pit Vipers. Highly venomous, rare, and no recorded bites.
There are many, many other NON-VENOMOUS SNAKES. For a comprehensive list with English, Chinese and latin names, please go to: https://www.flickr.com/groups/ark_hongkong_reptiles/ and scroll down; and click the name to find more images. Please add your own images.
PLEASE SEE THE NEXT BLOG
What to do if you get bitten
More facts and information about living with snakes in Hong Kong, and some amazing (and comforting) statistics
What snakes are commonly confused with the venomous snakes
Bonus: One other dangerous snake: Burmese Python - Python bivittatus(China), Mainly nocturnal. Diet: Warm blooded mammals up the size of a large dog. Not Venomous: A potential danger is present due to its size. Recorded attacks appear to be limited to animals.
AND YOU CAN DOWNLOAD THE FULL PDF GUIDE TO VENOMOUS SNAKES NOW AND HERE:-