Their unique appearance, vibrant color, observant behavior, ease of maintenance and pleasant dispositions make Rhino Ratsnakes (Rhynchophis boulengeri) one of my favorite species to keep. I maintain a small breeding group of Chinese animals and have had excellent success reproducing them in captivity. Here is a brief explanation of what I do during the breeding season and the results that follow.
October marks the final opportunity for my snakes to eat before brumation begins. I offer the last meals in late October. Temperature is maintained at normal levels throughout most of November to allow them to digest. At the end of November, usually within a day or two of Thanksgiving, I begin the winter brumation. I like to step the temperature down from 65-70°F for about a week, then 60-65° for another week and finally 55-60° for the rest of the cooling period. Someday, I will have the means and space to cool an entire room. That day hasn’t come yet, so I have had to get creative in creating my own brumation chambers. I initially used a small wine fridge. It worked, but it was smaller than I liked, requiring me to keep the snakes in six quart plastic shoeboxes, and the particular model I used wasn’t able to get as cool as I wanted. This year I used a chest freezer that stayed outside on my porch. I taped heat cable on the bottom and sides of the inside of the freezer which was controlled by a thermostat. Midway through December temperatures in Central Texas exceeded 80° outside and I had to plug the freezer into the thermostat just to keep it cool enough! I set the heat cable to 58° and the freezer to 63°F. This swing was large enough the heater and freezer didn’t fight each other and the temperature was usually 59°. The snakes were kept in Sterilite containters measuring 15 x 11.5″ with sphagnum moss substrate and a water bowl. Whenever I replaced the water, the snakes would climb into the bowl-where the water was warmer than the air temp- which would then overflow onto the moss and soak the entire container. I countered this behavior by adding a couple ice cubes to each water bowl when I refilled them. The ice cubes melted before long, but kept the water cool enough the snakes didn’t seek it out as their own personal jacuzzi.
In the middle of February I return them to their separate cages where the temperature is determined by the ambient air temperature of my house, usually 60-75° with brief fluctuations approaching 82° as summer approaches. I offer food once they appear to have settled back into their new surroundings and almost 100% of the time, the males will refuse to eat. This is a good sign however, since it indicates their desires are to mate and not to eat. The females are more than happy to see food again and eat readily.
About a month later, towards the end of March the females will approach their first shed of the year. I try to capitalize on the pheromones released at this time and introduce the male to the female’s cage right before the shedding occurs. You may or may not observe copulation but don’t pull the male! I leave the male in with the female until it’s obvious she is gravid. Only when I’m sure she is gravid, and is approaching her prelay shed do I separate the pair. This usually happens in May or early June for me.
The prelay shed is easy to identify. It seems to take longer than a normal shed and the females get much more blue. Personally, I think they look miserable! Most will hide or submerge in their water bowls for what seems like weeks until all-of-a-sudden, they are no longer blue, their eyes are no longer cloudy and you can count on them shedding within a couple days. When I see the onset of their prelay shed, I separate the male and provide an egg laying box for the female to deposit her eggs. I use a six quart plastic shoebox with about an inch of damp sphagnum moss inside and a hole cut in the lid. Within 6-20 days (usually 11,) I can expect 6-12 eggs to be laid. I remove them and place them in a plastic shoebox on top of vermiculite mixed 1:1 by weight with water. Then I find a spot in my house I think will stay around 78° and that’s where the egg box stays for about 60-80 days. Living in Texas, there are certainly fluctuations in my house and I know the eggs experience temperatures as low as 72° and as high as 84°. Incubated in this way, eggs hatch in about 70 days (68-77d.)
Establishing neonates is the only aspect of Rhino Ratsnake husbandry that isn’t all peaches and rainbows. However, I have learned more in a couple months caring for hatchlings than I ever could have raising only adults. They are much more resilient than they look and really aren’t as difficult to get feeding on their own as some keepers might suggest. As more people become successful in reproducing this captivating species, I can only predict the prey preferences of future generations will become more and more in line with pinkie mice.
I cannot get over how cool these snakes are! They watch me when I’m in the room and most of them rest on their perches in what would be plain view if they didn’t blend in so well with the plants. They are active enough to keep my interest, yet so calm and observant as to remain easy to handle. I am happy to interact with them in my collection and am excited to introduce others to this wonderful little green unicorn snake.