Breeding sugar gliders should only be done when you have obtained the proper information to do so without inbreeding. Getting gliders from two different sources does not indicate they are not related. Sugar gliders are shipped all over the world, so obtaining two gliders that are related is a very real possibility. Please do your research before you purchase a breeding pair of sugar gliders.
It is recommended to own sugar gliders for a minimum of a year, or more, before you venture into breeding them. Before you breed sugar gliders, you should have a complete knowledge of them and genetics. Please read Determining Genetic Compatibility in Sugar Gliders . This will give you a start of the information needed. There is a lot to know before you begin breeding. Please take the time to know about sugar gliders first, their behaviors, body language, what their sounds mean, how to bond with them, introduction methods, safe toys, know vendors to recommend, etc... You need to be able to pass all of this information down to those whom are adopting your joeys. All of this information is in addition to knowing all the ins and outs of breeding, genetics, rejection, cannibalizing, etc... This is why we recommend owning them for a minimum of a year before you venture into breeding. For more information on breeding issues, please click HERE.
It is recommend to find a reputable breeder to use as your mentor. There are several breeders that are willing to help educate you on basic glider knowledge as well as all of the breeding aspects. As breeders, we take this commitment very seriously. A good breeder will start working with you throughout a very long mentoring program; a program that may last up to two years. It will start with a pet-only pair of gliders to help you in basic glider ownership. The mentoring will continue from basic husbandry to the education needed to become a breeder. Once it is determined that you are ready, then a breeding pair will be set up for you. The mentoring continues as your breeding pair matures and begins reproducing, then on through the growth of the joeys. Mentoring can continue to assist in the process of home placement of the joeys. Finding a mentor is an excellent tool to the introduction of breeding sugar gliders.
Sugar gliders have an estrus (heat) cycle every 29 days. Females can begin going through estrus as early as 4 months old, or 16 weeks out of pouch (OOP). A female is pregnant for 16 days, after which point the immature joey migrates to the pouch where it will stay and nurse for approximately 70 days. Once the joey fully emerges, or comes OOP, this is considered their birth date. Joeys should remain with their parents until they are a minimum of 8 weeks OOP; most breeders opt to keep them until they are 10 weeks OOP.
To determine the Kinship and Percentage Het using the charts, please click on the following links:
If you are interested in breeding for the Mosaic trait, I encourage you to read this:
New to breeding and need a contract? Click HERE for more information.
Males: 12 weeks OOP
Females: 16 weeks OOP
Male joeys can become sexually mature as early as 12 weeks OOP (3 months old). At this point, they may or may not have their bald spots. Please do not rely on the presence of their bald spot or chest scent gland to determine if they are sexually mature.
Female joeys can become sexually mature as early as 16 weeks OOP (4 months old). There is typically no outward signs of a female becoming sexually mature.
Not all gliders will mature at these young ages. But it is in their best interest for us to presume that they are and manage them accordingly. Males should be neutered before 12 weeks OOP or separated from all females to prevent unwanted pregnancies.
Females should not be housed with intact males at this young age to prevent unwanted or premature pregnancies.
Will they inbreed? YES!
Sugar gliders in captivity do not realize that this is my mother, sister, father or daughter. If a female comes into heat, any mature mature, intact male will do "his job" and breed the females in the cage. If you have young joeys, I personally recommend they be separated from their parents at 10 weeks OOP to prevent potential breeding problems.
If you have intact males with females, THEY WILL BREED
Sugar gliders, when paired properly for breeding, will reproduce some very pretty colors. There are a variety of color variations that can be selectively bred. Before breeding any sugar glider, please ensure they are genetically compatible.
Standard gray: This is the most common color of sugar gliders. They range in shades of gray with a dark stripe running from its tail to the tip of its head. They exhibit dark bars that extend from their ears to their eyes. This is a dominant gene. Sugar gliders that are "het" for other colors with physically appear to be a standard gray in color. (Het, or Heterozygous, is when they carry the gene to reproduce the color, but do not express the color themselves. This is proven when the glider is bred and has color offspring.)Variations of Standard Gray
Leucistic: Fur is solid white with no stripe or bars at the ears, will have black eyes. This is a recessive gene and must be paired with another glider with the same recessive gene to reproduce a leucistic.
Mosaic: Fur will be presented in a variety of patterns. Patterns and color are random. Gliders will have white hands. Some will have rings on their tails, known as a Ring Tail Mosaic. This is a dominant gene and only takes one glider of the pair to have the gene to reproduce a mosaic offspring. If the offspring do not exhibit the mosaic characteristic, they did not receive the gene from the parent and will not be able to reproduce a mosaic themselves (unless they are paired with a mosaic).
Variations of Mosaic
White Face: The absence of the bar that extends under the ear toward the chin. The white face characteristic can be bred with any coloration. This is a dominant gene and only takes one glider of the pair to have the gene to reproduce a white face offspring. If the offspring do not exhibit the white face characteristic, they did not receive the gene from the parent and will not be able to reproduce a white face themselves (unless they are paired with a white face).
White Face Blonde: The absence of the bar that extends under the ear toward the chin. The fur overall is a lighter coloration and has a golden hue. This is a dominant gene and only takes one glider of the pair to have the gene to reproduce a white face offspring. If the offspring do not exhibit the white face characteristic, they did not receive the gene from the parent and will not be able to reproduce a white face themselves (unless they are paired with a white face).
Creamino: The fur is a creamy color with a tawny, brownish stripe and has burgundy eyes. This is a recessive gene and must be paired with another glider with the same recessive gene to reproduce a creamino.
Platinum: The fur is a light silver color with a light grayish/taupe stripe. The stripe is narrower than is typically found on other color sugar gliders. This is a recessive gene and must be paired with another glider with the same recessive gene, or the leucistic gene, to reproduce a platinum. For more information about the theories behind the Platinum and Leucistic Genes working together, please click HERE.
White Tip: A glider that is standard gray in color but exhibits from a few white hairs to a large white tip on the end of its tail. This is a also a recessive gene.
Double Recessive: A glider that is a combination of two recessive colors in one glider that creates a solid white glider with red eyes. These are bred by crossing the five following recessive trait combinations: albino x lue, creamino x leu, creaming x plat, creamino x albino, and albino x plat. You can determine which combination the Double Recessive is by looking at the lineage. (*These are referred to as Ruby Leus by The Pet Glider.) Below are the descriptions of the four combinations of the Double Recessives:
With the albino versions, you cannot determine their color until they breed. However, there are some determining factors to observe when they come OOP; see the above descriptions for Albino x Leucistic and Albino x Platinum. A good determining age is between the actual OOP date to approximately 6 weeks OOP.
Gliders that are born solid white with red eyes from parents that carry the albino and leucistic gene is a potential sign of being a Double Recessive glider.
The percentage het for the offspring would be calculated by considering each color separately, just as you would any other glider.
Albino: A glider that is all white with red eyes. Albinos are generally born with a faint pigmentation including a yellow diamond, faint stripe, tip on tail or lining along the patagium and hands. This is a recessive gene and must be paired with another glider with the same recessive gene to reproduce an albino glider.
Caramels (click on link for photo & description)
Protecting Your Sugar Gliders:
Inbreeding Depression and How You Can Avoid It
By: Hannah Harris, Oberlin College
In our culture, the taboo against incest and inbreeding is highly pervasive. Most people have a sense that you shouldn’t ‘marry your cousin’ (and many states prohibit it!) or may know that the children of closely related individuals can suffer health and developmental consequences ranging from mild to severe. For centuries, agriculturists have known that inbred plants and animals tend to be less fit than their outbred counterparts. Even Charles Darwin, who married his first cousin Emma Wedgewood, often worried that his relatedness to his wife had negative effects on the health of his children, three of whom died at a young age .
But why is inbreeding so bad? What does parental relatedness have to do with the health and survival of an individual? As dedicated pet breeders you have a substantial interest in the quality, well-being, and reproductive capacity of your animals. Inbreeding represents a real potential threat to the health of your sugar gliders which means you have a responsibility to understand what can go wrong and how to protect your animals from harm.
Inbreeding and Inbreeding Depression
Inbreeding describes reproduction between individuals who are genetically similar. This usually means that parents are close relatives, although it is possible for individuals to have genes in common without sharing a recent common ancestor. Across a wide array of species inbreeding is associated with various deficits traits that relate to organisms’ fitness. In biology, the term fitness is used to describe an individual’s capacity to survive (viability) and reproduce (fecundity). On average, organisms with higher fitness are expected to produce more offspring over their lifespan and make a greater genetic contribution to the next generation.
The decreased health and survival that is observed in inbred offspring is known as inbreeding depression. Though not all species or populations are equally susceptible to inbreeding depression, in the wild, many species have innate tendencies, physiological mechanisms, and behavioral strategies that help them avoid mating with close genetic relatives. Inbreeding depression has been studied predominately in captive populations, like livestock, animals kept in zoos, or organisms studied in laboratories. However, inbreeding depression is also important to the study of conservation biology, the discipline that studies how to preserve diversity in nature and protect species from extinction. Inbreeding depression represents a threat to the survival of small endangered populations and therefore must be managed carefully if researchers want to save species from going extinct.
What Can Go Wrong?
Every species will respond differently to inbreeding: while some species have evolved to cope with it, others may experience severe effects. However, when inbreeding does have measurable consequences they are usually detrimental. Negative effects of inbreeding have been documented across a vast array of different types of wildlife, including plants, insects, snails, fish, birds, rodents, primates, and even humans. Inbreeding depression acts on traits that affect fitness characteristics including things like birth weight, growth rate, fertility, and ultimately survival. These effects can range from subtle deficiencies to dramatic developmental disorders or even lethal genetic conditions.
Some documented consequences of inbreeding depression include:
● reduced egg hatching rates in birds and insects [13, 17]
● low birth weight 
● low juvenile weight 
● reduced juvenile survival [6, 9, 12]
● increased susceptibility to disease [1, 3, 11]
● delayed onset of breeding 
● depressed sperm count in males 
● increased rate of miscarriages and stillbirths 
● shortened lifespan [9, 13]
Clearly, these are outcomes you want to avoid among your own animals. Inbreeding depression has consequences not only for the immediate health of individuals but for their well-being over their entire lifespan and the health and fertility of a population across generations.
Why Does it Happen? The Genetics Behind Inbreeding Depression
Most mammals have two copies of every gene in their body. Each copy is called an allele. The interaction of the two alleles of a gene produces an organism’s phenotype, the visible traits that an organism expresses. Every individual only has two alleles for each gene, but across an entire population there could be many more. Different combinations of alleles produce much of the physical variation we see across individuals.
For almost every gene, one allele is inherited from a child’s mother and one allele is inherited from a child’s father. Mom and dad might both give you the same allele for a particular gene or they might each give you a different allele. When an individual has two copies of the same allele for a particular gene they are considered homozygous for that gene; if instead they have two different alleles they are called heterozygous for that gene. It is possible for a single individual to be homozygous for some traits in their genome but heterozygous at others.
When mom and dad are related they already share a high proportion of their genes. This means they probably have a lot of their alleles in common. Therefore, when they reproduce, they are limited in the array of different alleles they can pass on to their offspring. Inbred offspring are more likely to inherit matching alleles at any particular trait, leading to an increase in homozygosity across the genome.
Why does that matter? Remember that organisms express a gene based on the interaction between their own two alleles, and different combinations of alleles result in different outcomes. The interactions between alleles in the most simple patterns of inheritance can be characterized as dominant or recessive. A dominant allele is always expressed when an individual carries it in their genome, even if they only possess one copy. If an organism is homozygous for the dominant allele or heterozygous and carries one copy of the dominant allele they will still express the dominant trait. In contrast, a recessive allele only appears in an individual’s phenotype if they carry two copies, that is, if they are homozygous for the recessive allele.
In many systems heterozygosity correlates positively with overall fitness such that individuals who are heterozygous for more genes throughout their genome have a higher lifetime fitness . Homozygosity itself is not inherently good or bad. The problem is that many mutations that disrupt an organism’s normal functioning are recessive alleles that can be successfully masked in heterozygous individuals but become damaging when they are expressed homozygously. They persist in a population because they are carried by heterozygous individuals who have the mutation in their genotype but don’t express it in their phenotype. This is true of many serious diseases in humans, including cystic fibrosis, sickle cell anemia, and Tay Sachs disease.
Those three disorders are extreme cases in which homozygosity at a single gene has devastating or fatal effects on the body. More often, complex functions like disease susceptibility, growth rate, or reproduction are influenced by multiple genes. As inbred individuals become increasingly homozygous across their genome over generations of inbreeding, they are more likely to accumulate recessive alleles homozygously and express deleterious mutations in their phenotype. Each individual mutation when considered independently may have only a small effect on an organism’s fitness, but when mutations accumulate at multiple sites across the genome the total effects can be severe.
When Heterozygosity Really Matters
For some traits, heterozygosity itself if very important for individual fitness. One example is the major histocompatibility complex (MHC), which is one of the most important components of the immune system in mammals. The MHC is made up of multiple genes which code for proteins that help the body recognize pathogens and coordinate an immune response. Individuals who are heterozygous at MHC genes can produce a greater variety of proteins that can detect a greater variety of pathogens, meaning that their bodies are inherently more prepared to fight off sickness and disease. MHC represents a clear case where you can imagine a direct relationship between homozygosity and decreased fitness resulting from an increased susceptibility to disease.
A Real World Case Study: Scandinavian Grey Wolves
Grey wolves had not been seen in Sweden for decades until a new breeding pack was discovered unexpectedly in 1983 [Vila]. DNA analysis suggests that this new pack was descended from a single pair of wolves who had migrated from a neighboring population in a nearby country, most likely Russia. Throughout the 1980s, the new Swedish population remained very small and very isolated. Inbreeding likely became common after the original founder wolves died and siblings began mating with each other . Since its reappearance the Swedish population has closely monitored for conservation purposes, so researchers know detailed information about the relatedness of individuals, as well as demographic, genotypic, and fitness characteristics.
Studies on the captive zoo population of grey wolves showed that inbreeding depression could have devastating effects in these animals. The population maintained in Scandanavian zoos is descended from two pairs of wolves who were brought in from wild in the early 1950s and 60s. Both pairs were full siblings (brother and sister) and the siblings were mated to initiate a captive breeding program.
An analysis by researchers from the University of Stockholm observed some striking patterns in the fitness of inbred individuals. Researchers documented a dramatic increase in homozygosity and a dramatic loss of genetic variation in the population overtime with real consequences for individual fitness. As expected, inbred wolves showed decreased heterozygosity at many points in their genomes . Wolves who were more inbred were smaller, lived shorter lives on average, and had lower rates of reproduction . Inbred wolves also developed a form of hereditary blindness. Wolves with the condition were born being able to see but lost their vision entirely within their first six months. The condition shows a complicated pattern of inheritance, but only appears within the most inbred families. These blind wolves were more likely to die before they reached reproductive age than sighted wolves .
Studies of the wild Swedish population throughout the 1980s, 90s, and early 2000s suggest that these wolves were experiencing high levels of inbreeding and suffering some of these same consequences. Analyses of genetic similarity and homozygosity showed that wolves in the wild had similar levels of genetic diversity as the captive zoo population . Compared to the neighboring population in Russia and the historical Swedish population that was sampled through taxidermied museum specimens, the current population in Sweden has very low levels of genetic diversity . Importantly, younger wolves were more homozygous than older wolves, indicating that homozygosity has increased since the population was founded . In 2005 a group of researchers determined the degree of inbreeding for all the wolves in the population and found that many individuals shared as many alleles as if they were full siblings, even when they were descended from different sets of parents . As seen in studies of captive populations, wolves who were more inbred had lower reproductive success than outbred individuals; pups born to inbred females have lower survival rates than those born to more outbred wolves .
Then, in 1991, a male wolf migrated from another population to join the Swedish group. The impact of his contribution of new genetic material were rapid and profound. The population suddenly expanded exponentially from a single breeding pack to over 100 individuals as fertility rates and pup survival increased . Genes from the new migrant spread rapidly throughout the population and account for a significant increase in heterozygosity and restoration of genetic diversity since his arrival . This single male wolf has a disproportionately large influence on the genetic make-up of the present population and the majority of births that have occurred since his arrival can trace their ancestry back to his genetics .
The Scandinavian grey wolf population is just one group that seems to have rapidly rebounded following the contribution of new genetic diversity to the reproductive pool. The increased success of populations following the arrival of diverse individuals is known as genetic rescue, and this is not the only compelling example of this phenomenon. It is important to remember that such dramatic improvements do not erase the damaging effects caused by generations of inbreeding. But the rapid rebound of this population following the contribution of a single individual speaks to how devastating inbreeding depression can be for the health of a group of animals.
How You Can Protect Your Animals
In the wild, juvenile sugar gliders are kicked out of their natal territories before they become capable of reproducing and disperse away from their birth sites to found or join new communities of gliders [14, 15]. This helps prevent gliders from reproducing with other individuals in their own family. In captivity, animals don’t have this option, which means breeders need to be responsible about managing where they house young animals once they reach reproductive age, around 8-12 months . Current information provided by breeders’ experience within the United States indicates that reproductive ages are much closer to 3-4 months.
Maintain careful records of the individuals you use in your breeding programs to make sure you are always aware of the degree of relatedness and recent common ancestors between any two reproductive adults. Kinship charts such as this one http://glidernursery.webs.com/kinshipchart.htm are a helpful resource when thinking about arranging pairings between gliders. Keeping detailed pedigrees has the added benefit of allowing you to monitor the inheritance patterns of desirable traits like coat coloration, which can help you think about breeding for specific traits in the future. There is no way to determine how much inbreeding is “safe” versus “too much” so it is important to avoid inbreeding as much as possible. If your breeding population is small consider sharing animals with other breeders in your area to maintain genetic diversity in your own population.
1. Amos, W. et al. (2001). The influence of parental relatedness on reproductive success. Proceedings of the Royal Society of London B, 268: 2021-2027.
2. Charlesworth, D. and Willis, J. H. (2009). The genetics of inbreeding depression. Nature Reviews Genetics, 10: 783-796.
3. Coltman, D. W. et al. (1999). Parasite-mediated selection against inbred Soay sheep in a free-living, island population. Evolution, 53: 1239-1267.
4. Danchin, É. et al. (eds.) (2008). Behavioural Ecology. Oxford, UK: Oxford University Press.
5. Ellegren, H. (1999). Inbreeding and relatedness in Scandinavian grey wolves Canis lupus. Heridatus, 130: 239-244.
6. Frankham, R. 1995. Conservation Genetics. Annual Review of Genetics 29: 305-27.
7. Gaggiotti, O. E. (2002). Genetic threats to population persistence. Annales Zoologici Fennici, 40: 155-168.
8. Ingvarsson, P. K. (2002). Lone wolf to the rescue. Nature, 420: 472.
9. Laikre, L. and Ryman, N. (1991). Inbreeding depression in a captive wolf (Canis lupus) population. Conservation Biology, 5: 33-40.
10. Liberg, O. et al. (2005). Severe inbreeding depression in a wild wolf Canis lupus population. Biology Letters, 40: 17-20.
11. O’Brien, S. J. et al. 1985. Genetic Basis for Species Vulnerability in the Cheetah. Science 227: 1428-1434.
12. Oostermeijer, J. G. B. et al. (2003). Integrating demographic and genetic approaches in plant conservation. Biological Conservation, 113: 389-398.
13. Saccheri, I. et al. 1998. Inbreeding and extinction in a butterfly metapopulation. Nature 392: 491-494.
14. Tyndale-Biscoe, H. (2005) Life of Marsupials. Melbourne, Victoria: CSIRO Publishing.
15. Tynes, V. (ed) (2010). The Behavior of Exotic Pets. Sweetwater, TX: Wiley-Blackwell.
16. Vilà, C. et al. (2003). Rescue of a severely bottlenecked wolf (Canis lupus) population by a single immigrant. Proceedings of the Royal Society of London B, 270: 91-97.
17. Westemeier, R. L. et al. 1998. Tracking the Long-Term Decline and Recovery of an Isolated Population. Science 282: 1695-1698
Allele- one of two or more versions of a single gene
Conservation biology- the biological discipline that studies works to preserve biodiversity in nature and protect endangered species and populations
Dominant- when one allele can mask the expression of another. A dominant allele is expressed even if there is only one copy.
Fecundity- fertility, the ability to reproduce; the reproductive rate of an individual or population
Fitness- the capacity of an individual or population to survive and reproduce. An organism’s fitness depends on both viability and fecundity. Individuals with higher fitness are expected to make a greater contribution to the next generation. Fitness is inscribed in an organism’s genotype and manifested through its phenotype.
Gene- a stretch of DNA that contains the information for a specific trait
Genetic rescue- a phenomenon in which inbreeding depression in a struggling population can be partially reversed by the introduction of genetically diverse reproductive adults from other populations
Genotype- an organism’s genetic sequence describing which alleles the individual possesses for a given trait
Heterozygous- when an organism possesses 2 different alleles for a given gene
Homozygous- when an organism possesses 2 copies of the same allele for a given gene
Inbreeding- the process of reproduction between individuals who are genetically similar. This often means that parents are close relatives; it is possible for individuals to have genes in common without sharing a recent common ancestor.
Inbreeding depression- the biological term used to describe reduced survival and fertility of the offspring of related individuals
Major histocompatibility complex (MHC)- an important component of the vertebrate immune system that allows the body to recognize and respond to invading pathogens. Heterozygosity at the multiple genes that encode MHC correlates closely with individual fitness and allelic diversity for MHC genes across a population correlates with population health and persistance.
Mutation- an event that changes the sequence of DNA inside an organism’s cells. Mutations might or might not affect an individual’s phenotype. If there is an effect, a mutation could improve an organism’s fitness but is more likely to disrupt normal functioning and cause some degree of damage.
Outbreeding- the process of reproduction between individuals who are genetically different and not closely related
Phenotype- the physical traits an organism expresses based on the interactions of its inherited genes with the environment
Recessive- describes an allele that must be present in two copies in order to be expressed in an organism’s phenotype
Trait- a genetically determined characteristic
Viability- the ability to live and survive; capable of normal growth and development
 One example of this in humans in blood type. Each person carries just two alleles that determine their blood type, but across the entire human population there are three blood type alleles: A, B, and O. An individual’s blood type is determined by the interaction of the two alleles they possess. A and B alleles are both dominant while the O allele is recessive:
Allelic Combination (Genotype)
Blood Type (Phenotype)
To download a copy of this article for personal use, not to be copied or re-published without express written consent from Shelly Sterk, Glider Nursery.