Are Snakes Venomous or Poisonous? Let Us Understand the Difference.

Snakes often invoke a sense of fear and fascination due to their mysterious nature and the potential danger they pose. This duality captures the imagination of most individuals and compels many to learn more about these intriguing creatures.

A common question that arises when discussing these reptiles on our herping trails or while attending rescue calls is whether snakes are venomous or poisonous. While these terms are frequently used interchangeably, they have distinct meanings in the world of biology. Let us try to understand the difference between venomous and poisonous snakes and why this distinction is important.

Venomous vs. Poisonous: Understanding the Difference

Venomous Snakes:

Venomous snakes are those that inject venom into their prey or aggressors through specialized structures such as fangs. Venom is a toxic substance that is actively delivered via a bite or sting. When a venomous snake bites, it uses its fangs to inject venom from glands located behind its eyes. This venom can have various effects, such as immobilizing prey, aiding in digestion, or deterring predators.

Here in India, we have the infamous "Big 4" venomous snakes to keep an eye out for:

1. The Indian Spectacled Cobra (Naja naja): This iconic snake with the unforgettable hood has potent neurotoxic venom, affecting the nervous system.

2. Russell's Viper (Daboia russelii): This heavy-bodied viper packs hemotoxic venom, which disrupts the blood and wreaks havoc on tissues.

3. The Common Krait (Bungarus caeruleus): This slender, nocturnal snake also wields neurotoxic venom, making it a nighttime threat to be aware of.

4. The Saw-scaled Viper (Echis carinatus): Look out for the rough scales on this viper, because its bite delivers a hemotoxic punch.

The Big 4 Venomous Snakes of India

Poisonous Snakes:

Poisonous snakes, on the other hand, are those that deliver toxins when they are ingested or touched. The key difference is that poison must be ingested or absorbed through the skin, whereas venom is injected directly into the bloodstream through a bite or sting. True poisonous snakes are extremely rare.

One example often cited is the red-necked keelback (Rhabdophis subminiatus), which is both poisonous and venomous and can sequester toxins from the poisonous toads it eats, making its own body toxic if ingested.

Red-necked keelback (Rhabdophis subminiatus)

The Science Behind Snake Venom

Snake venom is a complex mixture of proteins, enzymes, and other molecules that can have devastating effects on the victim. The composition of venom varies among species and can include:

·       Neurotoxins:  Affect the nervous system, potentially causing paralysis.

·       Hemotoxins: Destroy red blood cells, disrupt clotting, and cause tissue damage.

·       Cytotoxins: Lead to cell death and tissue necrosis.

·       Myotoxins: Damage muscle tissues.

These components allow snakes to effectively subdue their prey and begin the digestive process even before swallowing. Venomous snakes have evolved their toxic capabilities for several reasons:

·       Hunting: Venom immobilizes or kills prey quickly, making it easier to capture and consume.

·       Defense: Venom serves as a powerful deterrent against predators.

·       Digestion: Some components of venom start breaking down prey tissues, aiding in faster digestion.

The Ecological Importance of Snakes

Snakes play a crucial role in maintaining the balance of ecosystems. They help control pest populations, such as rodents and insects, which can otherwise become problematic. Furthermore, snakes are prey for various birds, mammals, and other predators, contributing to the food chain.

Snakes are fascinating creatures that have developed venom as a sophisticated tool for survival. While the terms venomous and poisonous are often confused, it is essential to recognize their differences.

The key takeaway from this blog is, that venomous snakes inject toxins through bites, while poisonous snakes are harmful if ingested or touched.

Understanding these distinctions helps in appreciating the complex biology of snakes and promotes a more informed and respectful attitude toward them. As part of our natural world, snakes deserve our protection and admiration for their unique role in biodiversity.