This is purely anecdotal, but I’m amazed at the number of rabbits in / around Boston compared to Houston and Austin, Texas. I’ve seen no more than a few each year in Texas vs several per week around Cambridge, Medford, and Somerville, Massachusetts.

That’s very interesting. I see several per week in my neighborhood in DFW. Same in my past DFW neighborhood. I’m guessing it’s much more localized than just metro/city. Certain suburbs might be much more suitable.

When I lived in Austin it seems like rabbits swarmed the neighborhood every third year or so, it was quite an irregular pattern.

Living in Stockholm now, I'm surprised by the number of European Hares I see when out for a night run or dog walk.

My dog lived in harmony with Texan rabbits, but there's something about the hare that makes him... curious. Maybe it's the big ears?

Different climates. Desert animals became much more nocturnal to avoid the heat. Primary production in Boston is also higher probably. More plants will sustain more rabbits.

Many cities sport large enough feral cat populations that rabbits are rare.