To breed boas successfully you must be properly prepared. In captivity snakes are generally prepared for breeding with a cooling period known as brumation. Similar to hibernation in mammals, brumation in reptiles is a period of dormancy during the colder winter months. Brumating snakes can eat during this period, but in general they won’t since the temperature is lower, they are less active (sometimes not moving for weeks or months) and digestion is difficult or impossible. Snakes will still drink during brumation so fresh water should always be provided. In captivity, a period of brumation is not essential to keep snakes healthy, but is required to induce breeding.
To prepare for this, feeding should be increased in the months leading up to brumation – typically August, September and October. This will ensure that your snakes are of a good weight for breeding, and is especially important for females. Your goal here is not to over feed, obesity is just as bad, if not worse, than being underweight. Rather, you wants your boas to be heavy and well rounded.
Feeding should then be stopped entirely in late October, or early November. A couple of weeks is needed to ensure that digestion is completed, and defecation has occurred. Any food remaining in the digestive system when the temperature is lowered can lead to illness and even death. If the snake does not defecate you can try to induce this by soaking it in luke warm water.
Once you are sure that the digestive tract is clear, and that your snakes are in prime health, you can reduce the temperatures for the brumation period.
What temperature for brumation?
The optimal brumation temperature and period differs from species to species. What works well for one species, could be severely damaging to boas from a different native climate.
Tropical boas, such as boa constrictors, usually do well with a night time temperature which slowly lowers to around 70 F, while keeping the daytime temperature around 85 – 90 F. With careful use of timers, a long, cool night can be controlled, while a short but still warm day helps to keep your boas healthy and maintain a resistance to parasites and disease.
For boas from temperate climates, such as the rosy boas, a cooler temperature in the high 50s F can be maintained throughout the brumation period of around 3 months. This temperature is then raised back up to normal husbandry temperatures in March.
Exactly how to control your temperatures will depend heavily on your climate, where your enclosures are kept, and how they are heated. A certain amount of trial and error may be necessary to ensure that temperatures are controlled properly, and a mixture of heat sources, timers, and possibly air conditioning may be required. Use of digital thermometers with a high/low memory feature will allow you to keep a close eye on your temperatures, and if at all possible you should set up brumation enclosures as a trial before introducing your boas.
Following these guidelines will give you a good chance of successfully breeding your boas. After a successful mating, the key to successfully raising the neonates is proper preparation. Ensure that you are well prepared for the care requirements, both of the gravid female, and the neonates after birth, and you’ll enjoy the wonder of breeding boas!