Being tropical snakes IT IS VITAL THAT THEY ARE NOT HIBERNATED OR BRUMATED. When a female Boa is put into a breeding schedule, as opposed to a maintenance schedule, the food intake should increased where possible to the point of being slightly overweight. A gravid Boa may not eat for up to 9 months so adequate reserves of body fat are essential. This should take place over a period of about 6 months, during this period, the temperatures in the tank should be progressively changed to a cycle that has a DTH of 90F (30C) and a NTL of 68F (20C). The start of this temperature cycling should be mid October and reach the full NTL and DTH by early December, the male (whose should be kept separately in similar temperature conditions) should be introduced to the female about the 3rd week in December. Mating should begin and continue through until February, by the 1st week in February the temperature cycling should be reversed progressively so that by the 3rd week in March the DTH is at high 80's F and the NTL back to low 80's (25C). If the female is gravid, she will normally refuse food for the period of the pregnancy. It is EXTREMELY important to keep the temperature in the females tank within the correct range during the period of pregnancy, fluctuations above or below usually result in either severe birth defects, or loss of the young altogether.
The gestation period of the Boa Constrictor is 4-8 months. As mating occurs over a period of time it can be difficult to state precisely when the fertilization took place. Temperature of the gravid female also seems to play some part in the equation so putting exact times on is difficult. Boas give birth to live young, and litter sizes vary from 6-65, the young are independent from birth and should be separated from the mother as soon as possible, Boas are not usually cannibalistic, but the young can be crushed by the bulk of the female. The young have been known to fight as well. Keep the young in small, separate containers, on paper towels with a supply of water. Change the paper whenever it gets soiled and keep a record of the birth date, sex if known, shed details and feeding record on a piece of paper taped to the top of each container. The young will shed, usually within 10 days or so of birth and will normally eat without any problem after the 1st shed.