J. wrote: “My son spotted this possum in City Hall Park this morning. Thought it was kind of funny to see, but does that mean more to come? Gross and damaging, right?”

Maybe not! I checked in with the City Hall Park Conservancy folks and they were aware that they had a possum shacking up in the park. They said the Parks Department is also aware of the critter, and the policy is to leave them be unless there is an issue. “The park maintenance workers actually like the possums because they say they keep the rats away!” said April Krishnan.

Indeed, they kill an estimated 5,000 ticks a season and catch and eat cockroaches, rats and mice.

Possums are docile and are not dangerous to humans or pets. USA Today did a fairly big story on them, sourced with the Humane Society, and said that the animal’s main defense is either laying motionless on the ground or hissing. The open-mouth hissing is simply a front — they are not aggressive animals.

Also on the possum vs. opossum debate:

“If you’ve been using the name ‘possum’ for North American creatures, you’re scientifically incorrect…The Virginia opossum is the only marsupial found north of Mexico, according to Merriam-Webster. Possums, as the animal is typically called, are a different type of marsupial native to Australia.”