I’m going to answer the question as if the questioner wants to bump into some polydactyl cats and they are tourists or live in an area. However, you can find polydactyl cats on the Internet because some breeders create them for sale such as the American Polydactyl (see picture below).
But where in the world are they more commonly seen than normal in the general cat population i.e., non-purebred cat population? I always think of Boston, Massachusetts, USA as the centre of the polydactyl cat world but I might be mistaken. Another place well known for polydactyl cats is Hemingway House in Key West, Florida, USA. Both are on the East Coast of America, one up north and one down the south.
It is also said that Wales, UK is a bit of a hotspot for polydactyl cats and the south-west of England. However, one should be cautious about saying that polydactyl cats are more common in Wales. This is because if one website such as Wikipedia states this, which it does, many other independently run websites restate it and it becomes fact when it might not be.
Wikipedia cites as an authority for Wales being a hotspot for polydactyl cats, the website The Spruce Pets in their article called “7 Amazing Facts about Polydactyl Cats”. The author of that page does not provide a reference as to why they state that polydactyl cats are more common in Wales. So, is the information correct? I’d bet that if you asked a Welshman or woman about polydactyl cats, they wouldn’t know about them.
A good source informs me that polydactyl cats are common in Yarmouth, Nova Scotia a seaport founded by immigrants from Boston – those pesky Boston polydactyl cats were being exported! In contrast, in a nearby town called Digsby, polydactyl cats are as rare as they are anywhere else because Digsby was settled by New York loyalists after the Civil War (Dr. John Bradshaw in his book Cat Sense).
If you want to see a polydactyl cat amongst the general domestic cat population, I think the best place to go is Boston, USA.
Why is this? Before I answer that question, as a reminder, ‘polydactyl cats’ is a reference to cats with more than the usual number of toes caused by a genetic mutation which hardly ever has deleterious side-effects. In other words, it is a harmless genetic mutation and in fact sailors treasured the extra toes on cats because they felt that they were better able to keep their balance on the deck of ships. That’s why they were ship’s cats and it is probably why there are more polydactyl cats on the east coast of America than elsewhere because they were transported on ships and then taken ashore where they stayed and procreated (no spaying and neutering in those days).
It would seem, and according to Dr. John Bradshaw, that in the early days of the establishment of the city of Boston, USA, a newly arrived cat produced a kitten with extra toes. That unknown kitten would appear to be the foundation polydactyl cat of Boston and in many other areas of the world as ships sailed from Boston. So, the ancestor of many polydactyl cats was a Bostonian.
By 1848 extra-toed cats were common in Boston. And, in 2021, it is estimated that about 15% of the domestic cat population in that fine city are polydactyl. That means that 15 out of every 100 cats that you meet in Boston will have extra toes.
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