A snake on the hunt

I found a large garter snake in the woods the other day..

Unusually, it did not try to escape, so I moved very slowly and started to photograph it.

Eventually it moved off, very actively scenting the air with its tongue.

It was only when I got back and looked at my photos that I realized that right in front of the snake was a very well-camouflaged toad that I had not even noticed. It is in the left foreground.

The toad knows perfectly well that the snake is an existential threat, so its mode of defense is to inflate itself to look bigger. If you look closely at the toad you will see that it is bloated and shapeless, and very, very fat: that is why!

The toad is doing a second thing: its legs are stuck rigidly out at right angles from its body, not a normal toad stance. This too makes it much harder for the snake to swallow it.

Snakes can eat toads, despite their poisonous parotid glands, the big puffy areas just behind the eyes. Garter snakes are immune to the poison (whereas dogs are not). You can see the parotid glands clearly on this other toad below, which is uninflated, and with its legs tucked in a standard stance.

The garter snake either decided the toad was too big (i.e. the defense ploy worked), or it was distracted by my presence, but after a while it moved past looking for fresh prospects. Here is my video clearly showing in closeup how it scents the air: https://youtu.be/kYGlzlPzqd0

You will notice that it moves its head from side to side as it flicks out its tongue. This allows it to “smell in stereo”, detecting and locating exactly where the strongest smells are coming from. It also probably helps with visual location, since its eyes are on the sides of its head. BTW, you can also see the toad breathing, proof of life!

PS I have been having trouble getting my videos to play to readers. This time, I uploaded it to YouTube and have given you the link to watch it there. I do hope it works, and I’d very much appreciate feedback in the comments.

PPS I found this video online of a garter snake trying to actually swallow an inflated and rigid toad. This is not for the faint-hearted: https://www.youtube.com/watch?v=IGpN0ibEp9U

A good AI summary of exactly how the toad inflates itself says: “This behavior—known as body inflation or lung inflation—is primarily accomplished through a rapid, forceful contraction of the buccal (mouth) pump. By keeping the glottis open and closing their nostrils, toads force air into their lungs until their body expands to appear larger and significantly harder to swallow.”