Actually alright crunching the numbers. If we group the animals that are usually picked for fursonas, I'd say canine-like are by far the most popular group, with dogs and wolves being the most popular species (you'll see jackals, coyotes, hyenas and foxes a lot too, compared to other groups, but they appear less often). Second place would be the deer-like, with white tailed deer being the most common (reindeer and caribou are also popular, but you'll never see, say, a gazelle). Third, big cats. Tigers, panthers, lions and puma are all extremely common (but you'll also see random choices like sabertooth, lynx and cheetah very frequently). Then, you have rabbits, most of them of the generic kind, quite often jackalopes, and sometimes described as another species (say, hares) without any changes. Fifth are bears of any kind. And also dragons if you include fantasy animals.
Note this list is for, furry-fandom furries. Like, classic style fursonas. For people who choose cartoon animal avatars, for example, domestic cats are actually the most popular.
