“They were just racing through the town,” said Mr. Stuart, who called a nonemergency police line. “They are in town because it is so quiet, because hardly anyone is about.”

There is also hardly anyone outside in San Francisco — except for the coyotes.

Residents in San Francisco have been under orders to practice social distancing for two weeks, leaving their homes only to buy groceries, go to pharmacies and participate in other essential tasks. The streets have been left to the coyotes, which seem to be venturing farther into the city because there are so few cars, according to Deb Campbell, a spokeswoman for San Francisco Animal Care and Control.

“We have had a lot more reported sightings of them in the streets,” she said. “They are probably wondering where everyone went.”

Social distancing has not increased wild animals’ populations, but it does seem to have changed their behavior in seeking new food sources, said Jim Fredericks, chief entomologist at the National Pest Management Association.

“What we are also seeing is that they are looking for food in places they had not before,” he said. “The part of the equation that is missing right now is people.”

Ever since Louisiana imposed a lockdown, causing restaurants to shut down, the rats in New Orleans are almost certainly wondering where the usual French Quarter crowds — and their trash — have gone.

“Animals are opportunistic and feed off trash,” said Claudia Riegel, executive director of the New Orleans Mosquito, Termite and Rodent Control Board. “The restaurants are producing a lot of trash, and right now, a lot of that is just gone.”