What do they eat? A baby Rubber can eat a pinky lab mouse from the time the mouse is a newborn till it is a couple days old. The mice grow fast, so you want to get them as young as possible. The pinky in the photo above is about as large as will be commonly consumed. Smaller would be better. They DO NOT eat meal worms, crickets, etc. If you happen to have some very small lizard eggs, or snake eggs (like those from Contia tenius), they will likely be eaten. But, as written in the Natural History page, the main prey item is baby rodents - mice, shrews and voles. A study of preserved specimens published in 1999 indicated that young Rubber Boas prefer lizards and lizard eggs, but specimens observed were almost exclusively from California where reptiles may outnumber mammals. In other populations, due to lack of choice (low lizard populations), nestling mammals are the exclusive diet. Stick with baby mice and your Rubber Boa will do well.

When do they eat? Baby Rubber Boas from the Pacific Northwest (and assumed to be similar for all other populations) generally do not have an opportunity to eat after they are born, and before the onset of hibernation. Thus, the first possible chance of eating is six months after being born. Still, some will not eat that entire first year of life until emerging from the second hibernation! That is a full 18 months from time of birth to first meal!!

The lesson from observing wild babies is - don't be in any hurry to get it to eat. This requires patience that many beginning snake keepers have not developed (nor experienced for that matter). Many expect a snake to eat at least once a week, and perhaps twice. Not so with young Rubber Boas. It is a small snake with a slow metabolism. Two pinkies in any given month is plenty, one is adequate, none is ok. As it grows, so will the consumption.

Another lesson from wild ones - keep it cool. The first year or so, before obtaining the first meal, they primarily stay underground where it is cool and moist. So keep it at 70 F (or as low as you can to a min of 65, or 70 during feeding attempts), and give it plenty of water and moist hide spots. Be prepared for the long haul, as it potentially may not eat until next spring. That is why you keep it at a cool temp, so it doesn't burn up it's reserves (which are plenty for a 1 year fast IF temps are cool, but not so if you keep it too warm!).

How to feed it? I would suggest offering a live pinky once a month, in its cage, under a piece of bark or other cover.

Place the baby, and some nesting material inside the cage. (You will note from this picture that the cage is lined with newspaper. It works fine although probably not the best since it does not hold moisture well unless continually wetted. But I make sure to use the Wall Street Journal only so they keep up to date with the latest financial trends. (Besides, it fits this custom cage nicely!)	.
Place the bark, hidebox, or even a piece of denim over the food as if it was a real nest tucked away. Walk away and don't disturb till morning. If you have multiple boas in one cage, you need to weigh each prior to offering the food so that incase you cannot visibly tell who ate, you can determine by subsequent weighings (plus you should always be keeping a record of past weights).

I like this method as it lets the Rubber Boa decide when it is ready to eat. It is not induced to eat too soon nor too often for normal growth. It also does not rely on gruesome (for the human) or stressful (for the snake) methods which may have to be repeated forever to get the snake to eat. The possibility of my Rubber Boa acting like my two year old child, insisting that the food must be prepared a particular way drives me nuts. Better to avoid that pitfall.

 

The Gruesome Method

Alternatively, they can be enticed into eating by braining a pinky and placing in a confined area with the snake. In the picture sequence below, there is some mildly graphic pictures, so if you are faint hearted or a mouse friend, be warned. But then why are you reading a page about a mouse-eating snake? Anyway, don't blame me if you don't like it.

See the feeding page on how to make a feeding container for this feeding method. Preferably the container should be small for a baby Rubber Boa - about the size of a single serving yogurt container. If the container is too big (like the one in the pictures below), the baby will have a very hard time obtaining leverage to eat. Alternatively, a large container could be lined to provide traction.

This is one of the males from RAAB Female #1. He was born in 2000, and this series of pictures was taken in the summer of 2001. In this photo, he has been placed in with several baby lab mice, but shows no interest at all.
So, I brained the pinky you see in the photo, and he immediately began nosing and smelling it. His brother was in with him, but removed once one of them started eating. (I was trying to double my chances of having a successful photo shoot!)
Eating begins. These photos are good examples of proper sized food items. They can eat bigger, but the baby mice used were good for easy eating. No constriction took place despite the fact that the mouse was still alive and squirming. This is common unless the prey is strong enough to potentially escape.
Here you can see how its lower jaw has to really stretch out to be able to swallow the meal.
Most of the way down. Due to the large size of the container, and the slick surface, I had to offer my fingers as support from time to time for the snake to push off of, and to push the mouse against. Better to use a small container for feeding so that this is not a problem, and the snake is kept in close proximity to the food.
Using a little gravity here to help get it down.
Final swollows. It took approximately 5 minutes to finish off this item.
Once Rubber Boas get into a feeding mood, they keep going till full. It is very easy to offer multiple items in one feeding session. They are naturally nest robbers, and an adult will suck down a bakers dozen of these little guys before even considering what it will do to the waist line. So, I left it alone to see what would happen.
Sure enough, the first piece of flesh it comes across, it latches on! No braining necessary. But, we got the wrong end here, which is common. You can see in this photo the lump from the first mouse, and how big of a meal two baby mice are for a young Rubber Boa.
The 1999 publication by Javier A. Rodriguez-Robles titled Gape size and evolution of diet in snakes (caution for any would be readers of this paper, it contains many errors.) reviewed the stomach contents of about 249 (not sure if that is the correct number even though it is stated on page 51 since in other places the accounted for number of specimens does not match) preserved Charina bottae. Of those who had identifiable meals, it was noted that 16 prey were consumed head first, and 6 were tail first. This does not necessarily represent actual % frequency, but shows that wild individuals normally ingest some prey backwards.

This fella ate two pinkies. That was a really good sized meal! You can see from the picture above that the bulge from the first mouse takes up a lot of room. Finishing off the second nearly doubled his body weight. I offered a live peryomicus baby a week later (a treat hard for them to refuse), and he still was not interested in eating. No problem, he's still small and working on digesting the first two (which were enough to last many months anyway). As a Rubber Boa grows, it will become a more aggressive feeder, consumption will increase, and special methods will likely (and hopefully) not be necessary.

© 2001 by Ryan Hoyer.