Odd King Snake Behavior

[Kettennatter]

I hope this is the right place to ask a question that I have not found an answer to yet. Out of my snakes only one is a king snake, so I have no other direct reference points as to king snake behavior.

The snake is not fully grown yet, and maybe 4.5 ft. in length. It eats well, about every 4-5 days on average, and will only take live food. (I feed mice at the current time.) The snake responds strongly to food, and the whole process is usually over in 15 minutes. The snake also sheds well, and I cannot detect any signs of illness or distress.

The snake is rather inquisitive, an escape artist and very alert, which I believe is common for king snakes. It gets startled easily, but settles just as fast. Handling is very easy, and the snake will use my arm to climb if I reach into the enclosure. I therefore handle the snake probably more than I plan to, simply because I need to get him back where he belongs when maintaining the enclosure. Unless startled, the snake does not act aggressively at all.

And here comes my question: The snake has periods during which it nips at itself during or after handling. These are not actual bites, but very quick nips, not causing any damage that I can observe. It doesn’t nip me. There is no hissing or any other defensive posturing involved. The snake appears calm until the moment it nips at itself. Putting the snake back into its enclosure will stop this behavior.

My first thought was that this could be a reaction to this snake’s very strong feeding response and sought to make sure it was adequately fed. But this did not stop the issue. There are also periods of time during which this behavior does not occur at all.

An internet search produced examples of king snakes actually trying to bite themselves, but I have not come across something like this. Did anybody observe similar behavior?