As a matter of fact my yard became a zoo, seriously.
There are pet owners who are lazy to take their dog for a walk, so they release them in early morning: 3:00 to 5:00 am or in other hours where they assume people will not notice or be home.
One of the dog found my yard as inviting place and made it its constant place, i'm too lazy to plan a stakeout, the dog doesn't come every night, it usually comes 3 nights a week.
Other unleashed dogs, also visit, probably follow the smell.
There is no real enforcement in my city of many rules, let a lone pet related.
Also, there are coyote that pass in the yard, but they are cat/dog friendly, they only eat dead animals or leftovers.
Also, there are also a few porcupines who made my yard part of their path for finding food.
There are many stray cats who visit the yard and find it nice, since it has a lot of sand and sun.
The coyotes and porcupines come from a nearby park.