Fox colouration is a vast topic, but below are examples of spotted foxes, as reported by My Fox Family (Hungary, 2018) and S. Brown (West Midlands, 2017). I would have to agree with the assessment made by others regarding these foxes; such spots could potentially be the result of novel colour genetics, rather than being health related. Without further veterinary or genetic testing, follicle damage due to parasite bites, vitiligo and leukotrichia are the only known causes of such spots in wild foxes, to date.
© My Fox Family (Left Image), S. Brown (Right Image)
Leukotrichia & Vitiligo
Leukotrichia and vitiligo are conditions that produce a white spotted effect within the coat of animals of many species. Animals of any age can be effected and it may progress in time, with the animal turning completely white or developing increasing patches of discolouration as it ages.
"Leukotrichia" is the technical term for what is generally considered to be an acquired de-pigmentation that occurs over an animals lifetime. It is usually progressive in nature, being triggered by illness, stress or environmental factors.
"Vitiligo" is a considered a heritable condition of the immune system that is then triggered by environmental factors. The conditions cause antibodies to be formed against pigment-producing melanocytes. It is the destruction of these melanocytes that leads to the observed de-pigmentation.
White Spotting
White Spotting is a known fox coat colour mutation of the farmed North American red fox. It is linked with the genes that cause leucistic mutations such as piebaldism and whitemark/ringneck morphs. The most common example can be seen in the exploited mutant form known as the 'Georgian fox'. The mutation for white spotting was originally observed in the Whitemark and Platinum foxes of the European fur trade, as described in the book The Red Fox by H.G Lloyd (1980), detailed below;
"Danish Fox Pelts - The Fox pelt on the right is not unlike those of Britain. The one on the left shows the lighter fur on the neck and behind the shoulders; the spiral in the tail is caused by twisting whilst drying. The three centre foxes are unusual in the degree of blackness and spotting in the fur (not due to ticks). The cross of dark fibers over the shoulder is more apparent in these than in the more common forms (Photographed with kind permission of Helge Walhovd, Aarus)."
Georgian Mutations of Silver Fox
The Georgian fox, also called the snow mutant, was first documented in Russia in 1943. It is a white fox with black spots on the face, back and feet, but it's markings are distinct in their organization from marble foxes. These foxes are often described as 'freckled'.
The typical Georgian white exists on a silver fox background, with most of the body being white, and patches of black along the back, on the muzzle, face, ears, and legs of the fox. It is distinctive from marble foxes in that their ears usually often solid black.
The gene is incompletely dominant, and is lethal in homozygous condition. Therefore, Georgian foxes should not be bred to one another, nor any other white series coloration besides marbles. These foxes were heavily restricted when they were first discovered during the period of the USSR, and for a time only existed in Russia. They now are present across Europe, but they are not present in the North American pet or fur trade; except for Russian domesticated foxes imported to the US. Georgian white can hypothetically exist with any other coloration (amber, burgundy, pearl, etc.), but only two variations are currently well documented (Georgian white and Georgian red) with another; the Georgian Brown fox, having been bred on a rare occasion.
It is also thought that the connection to genes and a light colouration, as seen in English spotted rabbits and Georgian White foxes, can cause
Georgian white coat color of red fox maps to fox chromosome 2 in the region containing KIT gene;
"The farm breeding of foxes began in Easter Canada in the late 19th Century... with the Georgian White (GW) morph first being described... in Georgia in 1943... Recently, we have shown that a mutation in the KIT gene causes platinum coat color in foxes. Allelic interaction among the GW and platinum coat colors has previously been established through cross breeding of GW and platinum foxes. The mapping of the GW allele.. is thus consistent with the results of the experimental breedings and suggests that GW is also caused by a mutation on the KIT gene"
Conclusion
The presence of spots in wild foxes, particularly those exhibiting unusual color patterns, highlights the complex interplay between genetic mutations and environmental factors. While conditions such as leukotrichia and vitiligo are known to cause similar depigmentation effects in various species, the possibility of novel genetic mutations driving these markings cannot be ruled out. To accurately determine the origin of these spots, thorough veterinary examinations and genetic analysis would be essential.
Genotyping and clinical evaluations could differentiate between acquired conditions like leukotrichia, which is typically environmentally triggered, and inheritable conditions like vitiligo, which has an immune-mediated basis. In addition, the study of established coat color mutations, such as the white spotting seen in Georgian foxes and other leucistic traits, could offer valuable insight into potential genetic pathways that may be involved in similar patterns observed in wild populations.
Recent research on the KIT gene and its role in leucistic coat patterns, particularly in farmed and domesticated fox populations, suggests that certain coat color mutations follow a pattern of incomplete dominance, resulting in unique color morphs but also introducing potential health challenges, such as reduced viability in homozygous individuals. Thus, any genetic variations found in wild spotted foxes would need to be examined not only for their phenotypic expression but also for their broader biological implications on survival and adaptability.
Ultimately, interdisciplinary research combining genetics, veterinary science, and ecology would be needed to determine the precise origins of spotted patterns in wild foxes. Such research could deepen our understanding of fox genetics and potentially contribute to conservation strategies, especially as coat color variation may play a role in camouflage, predator avoidance, and overall fitness in natural environments. Only through targeted research will we be able to answer the question of how the fox "got its spots" with scientific certainty.
Another report today of a black brush fox with white spotting by Taxidermist, Jessica Powell, July 2024 https://www.facebook.com/groups/955306247815225/posts/8250641221614988
Wild melanistic fox with partially melanistic sibling, London, both possess spots (by C. Pullum 2023)
Just adding "Spotty" captured on film by Kieran Hyde, May 2023
Just adding the research from www.britishcanids.co.uk also, @Foxforum Basil, which also backs the theories suggested by www.blackfoxes.co.uk and might explain current reports of wild white foxes carrying the red platinum gene.
The fox below by D. Hammond, has white spotting on their ears too.. possible it is hybridisation creating the pattern, leucism with white spotting one side and platinum morph the other?
Her "Dad" is very NARF too:
Platinum is a leucistic mutation of the cross morph, which occurs because of hybridization between Alaskan and Canadian melanistic lineages. So maybe similar is true for hybridisation of NARF and EU species creating the whitemark pattern seen in platinum's?
Or is it more like the Black Squirrels of Hertfordshire, with these Platinum foxes of the South?
Escapee in the same area. Full NARF. Home and secure.
While the platinum morph is a selectively bred mutation, it's appearance in wild foxes is puzzling. Historical records seem to be providing some answers.
Albino foxes do occur, but albinism and melanism don't exist together (opposites), so white silver foxes are all leucistic, not albino (these are all true albinos, seen in Southern England):
Then there are weird leucistic mutations seen in Scotland, like below by C. Templeton:
and elsewhere:
Just noticed Ruby off TikTok also has White Spotting
Just adding a post shared with us on Facebook by Dave Thompson, of a young fox with little white socks;
Below are the Whitby/Wildlife Aid foxes that were genotyped by Warwick (these foxes were assisted by several fox charities). The reporter is a bit muddled as they were not arctic fox (vulpes alopex) but suspected hybrids between EU red foxes (vulpes vulpes) and farmed North American red foxes (previously vulpes fulva); this was due to their size, behaviour and unusual colouration.
Farmed silver foxes can exist in a white colour morph called "arctic marble" which can cause some confusion. These fox cubs would be described as having a leucistic colouration with a whitemark pattern presentation.
It is hybridisation between two North American subspecies, both carrying the trait for melanism, that creates the cross pattern seen in North American red foxes, which is exploited and mutated in farms to produce the whitemark and platinum lineages. I suspect the hybridisation between EU and NARF subspecies in the UK might also cause such pattern mutations here, if the right genetics are present, but this cannot be confirmed at this time.
Studies that may be of interest;
White Spotting in the Fox
Morphology of mottling hairs in domesticated silver foxes
Peculiarities of breeding work with red foxes obtained as a result of dominant mutations
The inheritance of the platinum and white face characters in the fox
Platinum coat color in red fox (Vulpes vulpes) caused by mutation in autosomal copy of KIT
Georgian white coat color of red fox (Vulpes vulpes) maps to fox chromosome 2 in the region containing KIT gene
@onyx stewart Those piebald foxes are very interesting! We certainly have plenty of piebald foxes, some with what appears to be a whitemark/ringneck mutation.
I was interested to know they had melanistic foxes also, as they didn't import any silver foxes as far as I am aware, though our wild stock may have had released silvers introduced into the breeding circles by the time they sent British foxes to Australia, (I did find report of a "tame pair" sent to New Zealand, but they quickly died).
We also have usual leucistic whitemark/ringneck foxes that begin as fully leucistic foxes. It is an unusual trait attributed to fever coat, below is a photo of 'Angel' by Manuel Chimanksi, who documented her colour change for Black Foxes UK over 2019-2020;
Photo taken of a young lady assisted by the National Fox Welfare Society in 2017 after she was shot in the face and found wandering outside a supermarket seeking help. She sadly escaped from her rehabber and was not seen again;
Piebald fox by R. Pottinger from 2015;
What appears to be a platinum fox reported to Black Foxes UK in 2015. I wonder if this is an unreported escaped pet or it is was related to the female from the National Fox Welfare Society above (as was a similar area, though it may also have been an earlier sighting of that particular fox);
Leusicstic Whitemark fox, North Wexford, Ireland, sadly discovered by hunters first, Jan 2016;
Below are examples of spotted foxes from across Europe, as reported by Adele Brand, Tate Taxidermy and Sharna Richardson (2010-2021);
This is something that's fascinated me ever since I got interested in foxes a decade ago. I've been collecting images from around the internet showing spotted foxes here;
(You can click on each image to see date, location and a link back to the original source)
I've trawled probably hundreds of sites, forums etc,and so far I've only found examples from Europe. Never come across a single example of a wild American red fox with this spotting. I've even talked with taxidermists and fur trappers in America and none of them have come across it either, which makes it seem like it's unique to the European subspecies. Be interesting to find out if it occurs in the Australian fox population since they came from Europe. Haven't found any examples from there yet but it's pretty hard in general to find clear images of Australian foxes.
I recently acquired a vintage fox pelt that is covered head to tail in spots. Must have hundreds of them. It's been interesting to study as it seems the spots are only on the underfur, not the guard hairs. The fox itself is also huge, bigger than any of my other European fox pelts and almost as big as a farmed fox. I wonder if these foxes are consistently larger than a typical fox or if it's just an oddity? Unfortunately the spots don't show up well in photos because a lot of them are hidden among the longer guard hairs but here's a few photos anyway;
Size comparison with a farmed fox
Spots on the ears
Close up of some of the spots. You can see how it just affects the underfur and not the guard hairs. The whole of it's undercoat was like this. From pictures online the spots always seem more visible in summer coat or on cubs when the guard hairs are shorter.
I'll point out to anyone who does not know; I came across this photo and I read comments. Not one person asked "are those stripes?" So I asked David who had thought nothing of it and told me they had always been there. In the meantime I read everything from "wet coat" to fox rubbing up against something and that "they'll be gone soon enough" even though I pointed out the stripes had always been there. To prove a point I posted photos of the fox two weeks, a month and two months after the initial one...still striped. I never thought I'd see a striped fox!
There is the "ring" marks from drying furs but a ring pattern can be seen on a number of foxes photographed over the years and a specimen from Australia shows distinctive rings. This was a descendent of the foxes transported to Australia in the early 1800s for 'sport' therefore there must have been rings in the tails of some of its ancestors.
When it comes to fox coat patterns nothing really surprises me although it would be nice to know whether it is natural developed from cross-breeding or a health issue but a lot of pale coloured foxes existed -is this spotting the result of these breeding with regular coloured foxes as we do have dark spots or even small dark patches that appear on some foxes.
DNA testing only seems to take place when it is for a specific, narrow search because there is still the "just foxes" attitude. It would be great if any future DNA from foxes could look at a wider number of issues and at least record the findings on a central data base.
We are still learning so much about foxes.