Do Snakes Change Colour When They Die?

Snakes, like many other reptiles, undergo various physiological changes after death. One of the most noticeable changes is a shift in their colouration. While snakes do not “change colour” in the way that chameleons or cuttlefish do, their appearance can alter significantly after death, due to several biological and environmental factors.

Why Do Snakes Appear to Change Colour After Death?

  1. Loss of Blood Circulation
    When a snake dies, its circulatory system stops functioning, leading to a loss of oxygen and blood flow to the skin. This can result in a dulling or darkening of the scales, making the snake appear a different colour than it was in life.
  2. Dehydration and Desiccation
    As the snake’s body dries out, the skin loses moisture, which can make it appear faded or even translucent. In some cases, scales may shrink slightly, altering how light reflects off them, further changing the perceived colour.
  3. Bacterial and Fungal Growth
    Decomposition begins almost immediately after death, and bacterial or fungal activity can cause the snake’s body to take on different hues, such as green, blue, or black, as decay progresses. This may also cause the snake to bloat which may alter the profile.
  4. Exposure to Light and Air
    Oxidation, or exposure to oxygen in the air, can affect the pigments in a snake’s skin. This can lead to a darkening effect, similar to how certain metals rust when exposed to the elements. This is common in green snakes, where the green pigment starts breaking down and turning blue, after death.
  5. Temperature and Humidity Effects
    The surrounding environment plays a role in how quickly a snake’s body changes in appearance. Warm and humid conditions can accelerate decomposition, causing faster discoloration. Cold and dry environments may slow down the process, preserving the original colour for a longer period. In some dark fossorial snakes, dehydration may lead to a lightening of the colour, turning them greyish-silver.

Do All Snakes Experience This Change?

Yes, most snakes will show some degree of colour change after death, though the extent varies by species, environmental conditions, and the snake’s initial colouration. Brightly coloured snakes, like coral snakes or Bush Snakes, may show more noticeable fading, whereas darker species may simply become duller. Museum specimens frequently become bleached out after a number of years in preservation.

Conclusion

While most snakes do not actively change colour after death, their appearance can shift due to physiological and environmental factors. The combination of blood circulation loss, dehydration, decomposition, and oxidation can make a dead snake look significantly different from its living state. This natural process is similar to what happens with other animals, but is particularly noticeable in reptiles due to their unique skin structure.

A Spotted Bush Snake (Philothamnus semivariegatus), found dead on the road. Note the blue colour of the scales.- Photo: Sake van Wyk

 

A dead Western Natal Green Snake (Philothamnus occidentalis). Green snakes often turn blue as the green pigment starts breaking down. – Photo: Luke Kemp
African Snakebite Institute