Thursday 3 May 2012

Russell's Viper

Russell's Viper ( Daboia russelii ) is one of the Big Four venomous snakes in India. It is found throughout the India except the north-east. It belongs to the Viperidae Subfamily and Daboia genus.

Russell's Viper


The Russell's Viper averages at 4ft (1.2 m) in length and can grow to a maximum length of 5.5ft. They have a short and stout body but compared to most other vipers, it is slenderly built.


Identification of the Russell's Viper :
  
          1. Head :      They have a flat, triangular head which is clearly broader than the neck. The head has     small shaped keeled scales. The nostrils are quite large and conspicuous and are separated by a single nasal scale.
 
Head of a Russell's Viper.



          2. Dorsal Body :  Body is stout shaped and has shine-less pointed keeled scales. General body colour is brown, deep yellow, tan or dark gray with spots of dark brown or blackish colour present. Juveniles are of a darker colour compared to the fully grown adults which are more yellowish-brown. 

Pointed, keeled scales of the Russell's Viper. The patterns on the dorsal body are also seen.

          3. Ventral Body : Ventral body is of white or yellow colour with semi-lunar patterns in blackish or brown colour.

Ventral body with semi-lunar spots.

          4. Tail : The tail is small and pointed with faint or absolutely no patterns or spots in adults. Juveniles may have visible patterns on their tails.

It can be seen that the patterns in the tail are faint.

          5. Patterns on body :  Continuous or discontinuous eye shaped patterns are found along the length of the dorsal body, with each of them having a blackish or dark brown outer ring with a white or yellowish outer rim. The colour inside these spots may be of a colour darker, lighter or same as main dorsal surface or may be filled with same dark color as that of the border. These spots are present in three longitudinal rows from the head and generally become faint or absent in the tail. The spots on the side are more round in shape and are generally discontinuous.

 
Patterns on a Russell's Viper






































On this Russell's Viper, the colour inside the spots are same as the colour of the border.

The side spots can be observed in this picture. Generally they have a rounder shape and are discontinuous.

          6. Eyes :  The eyes are large, flecked with yellow or gold. They have a elliptical or slit shaped vertical pupil.

Eyes with a vertical pupil.
          7. Sound :  When the Russell's viper is threatened, it coils around, raises one-third of its body up and produces a hiss which sounds like a whistle. 

Russell's viper coiled with head in the center.



General Behavior :

 The Russell's viper is a nocturnal species, though it can be found in the day under trees or bushes basking. Generally sluggish but can become aggressive on provocation. The Russell's viper prefers to stay on the ground but can climb up to certain heights during adverse conditions. It is a silent species and generally avoids attacking when provoked. It gives a warning sound (whistle like hiss) and raises one-third of its body off the ground. Bites usually occur when people don't see it in its natural habitat and step on it accidentally.The bite can be just a snap or the fangs can hang on for a few seconds.


Venom : 

 The Russell's viper has venom which is hemotoxic. The venom is injected into the prey by its fangs which are like hypodermic needles. Envenomation symptoms begin with pain in the site of the bite followed by swelling. Bleeding from the gums and blood in urine is a common symptom. There is a drop in blood pressure and heart rate falls. Vomiting and facial swelling occur in one-third of the cases. Severe pain may last up to two weeks. Local swelling peaks in 48 - 72 hours. Death from kidney, respiratory failure may occur 1 - 14 days post bite or later.



  Early medical treatment and early access to antivenom can prevent and drastically reduce the chance of developing the severe/potentially lethal complications.

Immediate First-Aid for bites by Russell's Viper

  1.  Keep the victim calm and reassured. If possible, rest the bitten limb at a level lower than the victim's heart.
  2. Immediately wrap a constricting bandage just above the bite site. The constricting bandage should be tight enough so as to not constrict blood flow.
  3. Do not remove the bandage until the victim is in the hospital and receiving antivenom.



Tuesday 1 May 2012

Venomous or Non-Venomous


I have seen many people asking the question, "How can I identify venomous snakes ?" on various wildlife forums. One of the forum members answered saying all snakes with vertical slit shaped pupils are venomous. This is a common misconception. Granted , a vast majority of the viperids which are venomous have vertical slit shaped pupils, one cannot reach a conclusion that all snakes with vertical pupils are venomous and the ones without aren't. The King Cobra which is the longest venomous snake in the world has round pupils, and the Indian Rock Python which is a non-venomous snake has slit shaped pupils.

  Close-up shot of a King Cobra's head shows us that they have round pupils.


                        Indian Rock Python, a non-venomous snake has slit like pupils.


So, there is no one easy way to tell if a snake is venomous or non-venomous.The only way to find out if a snake is venomous is by identifying it. 

We can identify snakes using the following - size, colour, pattern or markings, scale texture, pupil shape, head shape, characteristic sound/growl/hiss, behavior, shape of tail, scale count,etc.

Identifying a snake helps during a medical emergency involving a snakebite or when reporting a snake in your house/garden to a rescuer. So it is essential you know to identify the snakes in your locality.





 


Venomous Snakes

India is home to more than 200 species of snakes and only a few of them have venom potent enough to cause harm to a human being.

These are the Venomous Snakes found in India


  1. King Cobra
  2. Indian Cobra / Spectacled Cobra
  3. Monocled Cobra
  4. Common Krait
  5. Russell's Viper
  6. Saw Scaled Viper
  7. Bamboo Pit Viper
  8. Banded Krait
  9. Malabar Pit Viper
  10. Indian Coral Snake
  11. Hump-nosed Pit Viper
 In my next post, I will go on to explain how to identify the venomous snakes mentioned above.
 





About me

Hi,

I am Adithyaa from Chennai. I work as a trainee Navigating Officer on-board a Merchant ship. I have created this blog to create awareness about snakes, especially about those found in India.