The Breeding Cycle
The breeding cycle of a sugar glider in captivity is quite different from that of a sugar glider in the wild. In the wild, sugar gliders will mate and have young once a year. In captivity, mating can occur year-round with as many as four litters of joeys being produced. The difference is probably because in captivity the diet and climate are more stable and constant throughout the year.
A female sugar glider’s estrous cycle is about 28 days. Ovulation will occur approximately two days after the onset of estrous (also known as heat). While a female is in heat, she may become slightly more agitated than normal and she may make a distinct calling sound to her mate that is a cross between an elongated hiss and a bark. If you are very familiar with your female sugar glider, you may be able to determine when she is in heat. However, most owners can not tell the difference. If she is housed with an intact male, it will become very obvious when she goes into heat because he will take a sudden interest in her that is quite noticeable. You will probably see him climbing onto her back, licking her cloaca and following her everywhere. When this behavior starts, mating will probably occur within 24 hours.
Once mating begins, your sugar gliders will not have much interest in food for about 24 hours. Some males become very aggressive while mating and may nip at the female’s back while mounting her. In retaliation, your female may crab a lot and try to walk away from him. This is normal behavior. You should not worry that the male is hurting her or raping her. Upon occasion, the male may actually wound the female during mating. If this occurs, you will see an open sore on the female’s back, usually near her shoulders. Open sores should be treated by a veterinarian to prevent infection (see Mating & Dominance Wounds). Also, you may need to separate the female from the male for a few weeks in order to allow full healing of the wound. If the male continues to reopen the wound, separation until the fur begins to grow back in will be necessary, which may take up to three months.
After mating, if the female is impregnated, gestation in the uterus lasts for approximately 16 days. At the end of the gestation period, one to four immature joeys will be born and make their way into the mother’s pouch. Most sugar gliders only have one or two joeys at a time, but three or four joeys can be born upon rare occasion.
During birth, the mother will lick a trail from her cloaca to her pouch. The underdeveloped joey, that is only about one centimeter long, will crawl up the trail, then drop into the mother’s pouch where it will find a nipple. Once the joey finds a nipple, it will place its undeveloped mouth around the nipple and the nipple will swell inside its mouth so that the mouth becomes attached to the nipple. The joey will remain in-pouch, attached to its mother’s nipple for approximately nine weeks.
It is very rare to actually witness the birth of a joey. It is more likely that you would notice the mother cleaning herself after a birth has occurred.
Once your sugar glider has given birth and has one or more joeys in-pouch, you may notice a slight swelling in the lower abdomen of your female sugar glider that will appear as one or two small lumps. You can gently feel your sugar glider’s belly to find out whether or not there are joeys inside the pouch. This must be done very gently or you may accidentally dislodge the joey from the mother’s nipple. If your female sugar glider is comfortable with you, hold her on your chest, then using one hand, slip your thumb under her arms and gently lift her chest away from yours, exposing her belly. Using the other hand, gently rub your thumb over her lower abdomen, below her pouch slit and above her cloaca. If she has joeys in-pouch, you will feel small solid bumps (one or more) to either side of her abdomen. Depending on how far along she is, they may feel like small, hard peas or larger. If she is not yet bonded enough to allow you to do this, you can check her with another person's help. Put her in a pouch, head down, then have the other person hold her. Gently fold the pouch down, exposing her lower body. Have the other person hold the part of the pouch that her head and arms are in, then you can gently pull her tail and legs out of the way so you can check her belly.
As the joey develops inside the pouch, it will become more noticeable. By the time the joey has been in-pouch for about four weeks, there will be a very obvious lump that is about the size of a peanut shell. When the joey is about a week or two away from coming out-of-pouch, you may start to see parts of the joey coming out of the pouch opening. It is not unusual to see an arm, leg, tail or ear poking out. You may also hear your female sugar glider start to sing to the joey. This is a loud chittering sound that is often accompanied by hard shaking that appears as if the mother is having a seizure. If you look inside your sugar gliders’ nesting pouch, you will probably see the mother laying on her back and her legs will be convulsing. This is normal and should not cause alarm on your part. (Jump to the section on Joey Development for further information on that topic.)
Most breeding sugar gliders will mate again within a few weeks of the time the joey comes out-of-pouch. It is not unusual for a nursing mother to have one or more joeys in-pouch along with the joey(s) that is out-of-pouch. My sugar gliders tend to produce one or two joeys every three months or so. The mother will produce different types of milk for the different-aged joeys. Make sure that she is being provided with extra portions of her entire diet to ensure that she be able to continue to supply enough milk for the multiple joeys.
Feeding your gliders a proper, nutritionally complete and balanced diet is crucial to the well-being of lactating females. If the female is not getting a nutritionally complete and balanced diet, the risk of rejection and/or cannibalization is highly increased. (For further information about proper nutrition, go to Feeding Your Joeys & Adult Gliders.) There are also two milk supplements available that some people recommend giving to a lactating mother. They are Wombaroo Milk Replacer and Brisky's Booster Milk. If you are already feeding your glider a nutritionally complete and balanced diet, these are not needed to help with your glider's milk production. However, it is a good idea to have the Wombaroo Milk Replacer on hand in case of joey rejection. (More can be read about that by going to the article about Hand Raising A Joey.)
Some breeders give their female sugar gliders a hiatus once a year from breeding so that she does not get overly fatigued from the stress of constant breeding. Separating her from her mate during the 2-3 days of her heat cycle over the course of 1-2 months is one way of providing this hiatus. However, careful observation of your gliders will be necessary so that you know exactly when the female's heat cycle begins so that you will know the proper time to separate them. Also, keep in mind that this may be difficult to do if she has newly o.o.p. joeys since the father is needed to help care for them.
Some females will instinctively give themselves a hiatus by avoiding the male while in heat. It is important to provide multiple nesting areas in the cage (if there are not newly o.o.p. joeys) so that she can easily do this, if she wants to. One of my females used to make a nest inside her exercise wheel for two nights while in heat. Any time the male approached her, she would literally kick him out of the wheel-nest. However, not all females will take this proactive approach, so physical separation may be necessary if the female seems to be getting fatigues by multiple breedings.
If the fatigue seems to be ongoing, then you should consider having the male neutered to permanently "retire" the couple from breeding. This is what I did with my Pepe & Bittah in 2008. Pepe was twice Bittah's size and the constant demand of supplying milk for his large joeys was taking a toll on her, in spite of her self-imposed hiatuses (she is the female cited above). Her overall health was much more important to me than her continued breeding, so Pepe was neutered. It is interesting to note that Bittah refused his advances entirely from July, 2007 until September, 2008. Each month while in heat, she moved to another pouch and refused him admittance until her estrous cycle was over. She then had one last joey in November, 2008. Overall, Pepe & Bittah had 23 joeys between September, 2003 until November, 2008.
Some have questioned whether it is okay to use male gliders as a "stud" to females they are not normally housed with. Using males for stud service is definitely NOT recommended with gliders. Although a male/female pair will readily mate with each other if the female is in heat, it is very difficult for us to determine when the female IS in heat and therefore to know when it's okay to "temporarily" introduce them to each other. Therefore, if they were introduced to each other at the "wrong" time of the month, it could be very dangerous to one or both of the gliders involved since gliders that are not properly introduced can and will fight with each other to the death. In addition, the males are very important in the role they take in rearing the joeys once they come oop. If the male is just used for stud service, then he would be removed from the female before the joey(s) went into pouch, much less came out of it. Therefore, the male would not be present to help with rearing the joey(s). This would increase the likelihood of joey rejection - either on the way to the pouch, at some point in pouch or once the joey(s) came oop. So, please, don't ever consider using males for "Stud Service" - it's just inadvisable all the way around.