Albinism, or a lack of the pigment melanin which is responsible for coloration in animals’ bodies, exists throughout the animal kingdom. But what is it, how does it affect frogs, and how common is it?
Albinism is a congenital lack of melanin, the pigment responsible for an organism’s coloration. Albinism is a recessive gene, meaning both parents must be carriers of the gene for albino offspring to be born. While this makes albinism rare in wild frogs, some species are selectively bred for albinism in captivity.
But how exactly do recessive genes work, and why do they make albinism rare? How is it encouraged in captivity? Does albinism have any effects on the frog’s life? Let’s have a look.
How Do Frogs Become Albino?
Albinism is a congenital trait, meaning it is present from birth. It is not possible for a frog to be born with standard coloration and then later become albino.
Additionally, very specific traits must exist in a frog’s parents to create the opportunity for it to be born albino.
Albinism is not a random occurrence. It is a recessive trait, passed down genetically from parent to offspring.
For a recessive trait such as albinism to present in offspring, both parents must exhibit the trait themselves, or be carriers.
Carriers have the genetic ability to have offspring with a recessive trait, but do not have the trait themselves.
How Common Are Albino Frogs in the Wild?
Since recessive traits like albinism require very specific circumstances to present themselves, they are relatively rare in the wild.
Unfortunately, albinism prevents animals from using any coloration-specific adaptations, such as camouflage or aposematic coloration, that others of their species would normally utilize.
This highly increases the risk of predation.
Frogs that would normally hide from predators camouflage become much more visible with albinism, and frogs that would typically deter predators with aposematic coloration are missing their normal “warning” colors.
This increased risk of predation thereby decreases the number of albino frogs that survive to sexual maturity and are able to reproduce.
For the albinism gene to be passed on, a frog with the gene, whether visually or as a carrier, must find and mate with another frog that also either carries or exhibits albinism.
It is also thought that some cases on albinism in amphibians could be caused by issues in early development. In such cases, an albino tadpole may ultimately develop into a non-albino adult frog (Arietta et al. 2020).
These frogs would not carry the gene for albinism except through coincidence, and would therefore likely be incapable of passing their albinism on to their offspring.
While it would never be possible to definitively count all the albino frogs on Earth, it is safe to say that there are very few in the wild.
How Common Are Albino Frogs in Captivity?
Many keepers of reptiles and amphibians like and actively seek out unique colors, or “morphs” of the animals they keep. These morphs are achieved through selective breeding.
For example, two wild-caught albino frogs could be bred to create captive-bred albino frogs. These captive albino frogs could then be the beginning of an entire captive albino population.
However, frogs are much less commonly bred in captivity, and specifically less commonly bred for morphs, as compared to reptiles such as snakes and lizards.
The pet reptile market is more established and larger than the pet amphibian market, resulting in lower demand for specialized captive-bred frogs.
Currently, very few species of frogs are available with albino morphs for keeping in captivity. Of those species being bred selectively, there are typically far fewer albino individuals available than there are non-albino animals.
As the amphibian keeping hobby and market increases, however, breeding of specialized frog morphs such as albino and others will likely become more common and readily available. However, this is ultimately speculation.
It is worth noting that selective breeding for specific traits in animals typically requires inbreeding, since the initial pool of wild-caught animals with a desired gene is typically extremely limited.
Sometimes breeders will even have to, for example, breed an albino frog to a non-albino frog to produce carrier offspring, and then breed those carrier offspring back to their own albino parent to produce albino offspring in the third generation.
Unfortunately, this inbreeding can result in a wide variety of issues, ranging from genetic disorders, to infertility, to deformities.
While this issue has not yet become a major one in the amphibian keeping community, issues that have arisen with morphs of specific animals common within the reptile keeping community are cause for major concern.
All of this goes to say that while albino frogs are vastly more common in captivity than they are in the wild, they are still very uncommon in captivity.
It will be interesting to see how (or if) this changes in the future as more and more people keep amphibians in their homes.
Are Albino Frogs Healthy?
Albinism can pose major health concerns in any kind of affected animal.
Melanin, the pigment lacking in animals with albinism, is responsible for protecting the skin from sun damage. Thus, albinism increases the risk of sunburn and skin cancer.
Additionally, the lack of pigment in the eyes of animals with albinism, which causes the red tint to the eyes that is commonly associated with albinism, makes the eyes much more sensitive to light. Animals with albinism sometimes have reduced eyesight, or may even be fully blind.
As mentioned previously, albinism also poses many major threats to wild animals that lose their species’ color-based adaptations to avoid predation.
Due to the lack of predators, and the ability of the caretaker to control environmental features, captive albino animals are vastly more likely to live healthy lives as compared to their wild counterparts.
However, this does sometimes require very specific care from a caretaker, beyond the usual requirements for the species, to keep the animal healthy and comfortable.
This article was written in collaboration with another Master Herpetologist certified by the Amphibian Foundation.
Sources
Arietta, A. Z. A., Rubinstein, A., Freidenburg, L. K., & Johnson, P. N. K. (2020). Multiple cases of hypomelanism in wood frog larvae (Rana sylvatica) associated with developmental retardation and mortality. Northeastern Naturalist, 27(4). https://doi.org/10.1656/045.027.0404