Around here, our storm drains are maintained by raccoons. You drive by at night and there are half a dozen sets of eyeballs staring out at you. Kind of creepy the way they reflect the car headlights. Anything you put down there better be encased in inch thick steel. Those raccoons can get into anything. On the other hand, I guess you could consider the raccoons to be your urban food cache! You don't even have to stash them in the sewers ahead of time. They just appear there on their own. You could fashion a spear to get them.

Hmmm, another idea would the migrating geese in the parks in the area. There are enough of those messy things to feed the whole town. You can walk up to about ten feet from them. So a bola made out of paracord and rocks would be all you'd need. Never thought of the raccoons and geese as being an "urban cache", but I guess they are.

Hey, can you eat coyotes too???!!! We've got those all over, but you'd need a rifle to get them. Not a technical problem, except for the pesky "no shooting" laws in town.