How do I tell if a snake is dead?
Unless you can see obvious trauma or other clues like ants or crows eating it, you should be very cautious with dead snakes.
One of their defensive strategies is thanatosis also known as tonic immobility where they are feigning death. This can also be employed in conjunction with musking, emitting a foul smell from the cloaca.
So not only do they look dead, they also smell the part. This is so that predators wil think it to be dead and decaying possibly from illness and will then rather leave them be.
Sometimes it’s harmless snakes that do this, like the hog nose snake, but some very venomous snakes also do this, and in my neck of the woods the rinkhals (Hemachatus haemachatus) is a Oscar recipient for playing dead.
Problem is, they can strike from that position if you come too close to it.
Hog nose playing possum.
Rinkhals that’s very much not dead!
But even when they are dead, don’t throw caution to the wind, a decapitated head can still bite up to an hour after death and envenomate.
Snake venom is also very stable and while still in the gland (no light or oxygen) will be active for a few days. If you handle a dead snake and put pressure on the gland and get pricked by the fangs you could also envenomate yourself.
So, be cautious of seemingly dead snakes and handle even obviously dead snakes with care.