More Snake Science

Have you ever read an account of a thirty, forty or more foot snake, and wondered if that could be true?

If the measurement came from the shed skin of the snake, it should be viewed with skepticism.


A couple of weeks ago, Estrella the boa constrictor shed her skin. To our delight, the shed was very complete with no scales scraped off and few broken pieces. We like to find sheds like this because it is one of the signs that a snake is healthy. Snakes with illnesses or injuries will often shed in patches, leaving loose scales throughout their cage.

Estrella’s skin was so perfect that we decided to do an experiment. We measured the skin, holding it straight but loosely so as not to stretch it. We also measured Estrella herself. Snakes are not cooperative about being measured. Even with two people holding her and two measuring, she did not stretch out completely straight. We compensated for this by adding 1 foot to her measurement - the estimated length of her curved section.


The results: Estrella’s length = 7’ 6” (213 cm). Estrella’s shed skin’s length = 10’ 8” (305 cm). That’s right. Estrella’s shed skin is 143% of her actual length.


Why is this? When a snake is “wearing” her skin, the scales overlap with thin connective tissue holding each thicker scale together. When she sheds, the scales lie flat, the connective tissue stretches out, and voila! The skin is longer than the animal who wore it.