Brown snake
So I was chatting to my neighbour and they mentioned to watch out as they’d seen a brown snake cross the road, and their son had seen it on the grass near our houses. Ah yes, the benefit of living one house away from a nature reserve.
One part of me wanted to check it out. I’ve lived in Australia for a while now and never come across a snake. At least not one in the wild. I like snakes, have had them around my neck and held a highly venomous snake in the wild before (a tricot rayé in Noumea - I didn’t know how venomous it was at the time!!!).
But then there’s the other part of me, the scientific, logical part, that knows eastern brown snakes are the second most venomous snake in the world!!! So no, I’m not going to go looking for this snake. In fact I had a chat with my munchkin about how if we see a snake we don’t go near it…
So what’s the deal with eastern brown snakes? Scientifically their name is Pseudonaja textilis. As mentioned, they are venomous. Why venomous and not poisonous? These two words both refer to toxins that inflict pain, illness, and sometimes death. The difference lies in how the toxin is delivered. Poison is absorbed or ingested. A poisonous animal can only deliver toxic chemicals if another animal touches or eats it. On the other hand, venom is injected. Every venomous animal has a mechanism to inject toxins directly into another animal, usually fangs or a stinger.
So the brown snake is venomous, but how venomous? Second most venomous in the world - what does that mean? It means it has a very low LD50 number. The second lowest in fact. LD50 stands for “lethal dose, 50%”. It is the dose that will kill 50% of animals it is tested on in the lab. For snakes the LD50 is usually referring to standard 20 g mice as the test animal. The brown snake has a subcutaneous LD50 of 0.0365 mg/kg and an intravenous LD50 of 0.01 mg/kg. The subcutaneous (which simply means below the skin) LD50 is the one to go by, as very few snakes can achieve anything other than this.
The upshot of all this is you do NOT want to mess with an eastern brown snake. They are fast moving and can be aggressive. They have even been known to chase aggressors and repeatedly strike at them. The good news is that less than half of bites contain venom and they prefer not to bite if at all possible. They react to movement, so if you encounter one the thing to do is stand very still and then slowly back away…
So that’s a little about the eastern brown snake.