In the weeks leading up to breeding season and during the months of breeding season, females may exhibit strange behaviors. These behaviors may not be shown in every female while other females may display almost all of the following behaviors. Some of the behaviors are subtle and difficult to quantify (like small color changes) while others are easy to spot (inverted basking). I find that there is one change that is common to all my females during breeding season – their shed cycles tend to be longer.
In the weeks just before breeding season many females will become aggressive feeders. A ball python that is normally calm or shy may come shooting out of its enclosure at the scent of prey. Reproduction is a taxing process for females. They lose an incredible amount of body mass when producing eggs. The aggressive feeding change is their way of packing their body with the energy that is necessary to produce eggs.
Some of my females get lighter in coloration in the weeks leading to or in the early part of breeding season. I don’t know why this happens - maybe hormonal changes influence the female’s color. The color changes are subtle – the head fading may become more noticeable, fading along the lower sides intensifies, blushing spots may get lighter, and the overall tone of the female may be lighter. The change is more dramatic in some females while others don’t seem to change at all. I consider these color changes a good sign. It seems to me that these females are going through changes that indicate a favorable breeding season. I don’t have any scientific data to back this up – it is just a casual observation.
For most of the year, ball pythons spend most of the daytime curled up in their hide boxes. During the middle and latter parts of breeding season I notice that my females thermoregulate more often. Females spend time on their hot spot and then move to cooler areas – even in the middle of the day; a time that that they usually spend hiding. Occasionally I find a female in her water bowl. Since this is usually an indicator that the snake has mites or that the enclosure is way too hot, I give this animal and her enclosure a good check up. If everything looks fine, then I chalk it up as her way of trying to thermoregulate and cool down. If it wasn’t breeding season, I would be concerned that something was wrong with the female in this case.
When breeding season is well under way and follicles are getting large enough to where they can be palpated I find that some females will curl around their water bowl. Other females will roll over onto their backs in an inverted basking position. I think that these females are just trying to get comfortable. Ball pythons eggs are huge compared to the snake’s size – it must be tough to carry the follicles and eggs in the months prior to deposition.
There are a couple of signs that indicate that the end of breeding season is near. Females ovulate before they lay eggs. This change is noticeable. See my article on ovulation for more information. Ovulation indicates that your female is going to lay eggs or slugs – something is coming out. Soon after the female ovulates she will begin to nest if provided the right materials. I keep my adult animals on cypress mulch. I let many of my girls lay their eggs right on the mulch. For smaller females or skittish females, I use a nesting box filled with sphagnum moss or mulch. Females use their body to roll out the mulch or moss and make and indentation that they can fit in. Some girls push their way to the floor of the enclosure. The mulch may get piled up higher than the snake’s body. A few weeks later females lay their eggs in this recessed nest and tightly curl their bodies around them.