Nothing prepares you for the shock of a home invasion. Early last summer, I came downstairs to make coffee in the morning and discovered we’d been robbed: On the pantry floor lay a brand-new bag of IAMS with a huge gash in it; the floor was wet, and the water in the cat’s bowl was cloudy. A mass of muddy little footprints led from the scene of the crime out the door. The cat door.

My boyfriend, Tim, and I knew exactly what had hit us. The perp was a Procyon lotor or so-called “bandit of the wild,” aka raccoon. This would be the first of many free meals Rocky and his relatives enjoyed at our expense between May and September.

Like most kid-free couples, we spoil our cat, Tito, to a ridiculous degree. He comes in and out of the house as he pleases all year round, through a large-cat/small-dog-size door in the living room wall. He doesn’t wear a collar — a prerequisite for a magnetic cat door — and enjoys access to dry food 24/7, which explains his weight: almost 20 pounds.

To a resourceful urban raccoon, our cat-coddling pad on Burlington’s Lakeview Terrace may as well have an “all-you-can-eat” buffet sign outside. The animal is not just an omnivore — consuming both plants and animals — but an “optivoire,” according to the Vermont Fish & Wildlife website, which translates as “opportunistic.” That means raccoons will eat whatever they can find, be it in the wild — grubs, bird eggs, carrion — or in the garbage can.

But given the choice, raccoons will pick cat food. On every occasion the critters broke into our house, they passed up nuts, cereal and everything else in the pantry to chow down on the chow.

Storing the kibble in heavy-duty containers didn’t deter them, either. One late night we caught a raccoon leaving with a container of dry food under one arm, like a football. Dinner to go. On the way out, she dropped the container, but not before slashing and puncturing it with her razor-sharp claws.

Of course, no after-midnight snack would be complete without a beverage. Raccoons live near water because they don’t have saliva glands. They wash their food in water before they eat it, to aid with digestion. Hence the murky water bowl and signature wet paw prints.

We tried raccoon spray to ward them off. Closed the pantry door. But looking back on it now, I appreciate the simple logic of a wildlife biologist I contacted last week. Parker Hall, who oversees rabies eradication in Vermont and New Hampshire for the U.S. Department of Agriculture, said firmly: “If raccoons have found they can come into the house and eat cat food, they will continue until you totally exclude them or make it so they cannot.” Apparently, they can smell it a mile away.

“Minimizing access points,” as he put it, meant closing off the cat door at night. Easier said than done. “Locking” it was a joke; the raccoons burst right through the plastic tab designed to hold the flap shut. We tried blocking the opening with numerous heavy objects, all of which they managed to maneuver or ram through. On numerous occasions, we awoke to the disquieting horror-movie sound of raccoons attempting to break into our house.

A cooler, weighted down by a big box of paper and a car battery, finally did the trick. On the outside, we rested a heavy table against the cat door opening.

But this nighttime arrangement restricted Tito’s freedom, and our own. We had to be home every night prior to the moment when our daytime cat access transformed into a nighttime revolving door for every hungry raccoon on the street. That’s not convenient when you’re out to dinner or on vacation.

Once the house was secured, Tito would meow below our bedroom window when he wanted to come inside. When he wanted to go out again, he’d come up to our room to demand a doorman. Among his quirks: In the five years he’s been with us, we’ve never seen Tito poop; he prefers the great outdoors to a cheap plastic litter box. So this was serious business.

Tim and I made a deal: He’d be in charge of letting Tito in; I’d let him out.

As a result, neither of us — especially me, the lighter sleeper — was getting sufficient shut-eye. During the day, we debated alternatives to what was clearly an unsustainable situation. House sitters — once thrilled to stay at our place overlooking the lake — started saying no.

That’s when we decided to try trapping. We borrowed two Havahart traps from different neighbors and baited them with the raccoon equivalent of caviar: wet cat food. The first time the trap slammed shut — in the dead of night, in the pouring rain — we suddenly realized we didn’t know what to do next. We couldn’t leave the animal confined outside all night.

So we loaded the first caged ’coon into my boyfriend’s old Volvo and drove it out North Avenue. It was surreal, to say the least, driving through the dark at 3 a.m. with a wild animal in the backseat. I couldn’t help noticing Rocky was very cute. Scary and kinda sad, too. We kept wondering if he was smart enough to get out of the cage and, if so, what he’d do to us.

The first release was nerve-wracking, but Tim had the foresight to bring heavy gardening gloves. As the raccoon ran off into the night, we thought our problem was solved.

It wasn’t. Our neighbor informed us the next day that any ’coon worth its stripes could find its way back from the New North End.

Plus, our strategy was based on the mistaken assumption that the raccoon population on Lakeview Terrace is finite. Every time we set one or both traps, we bagged another one. We took them farther away, to South Burlington, figuring there’s no way they could cross I-89. Chief among the raccoon’s predators is the automobile.

On our “best” night, we caught three raccoons within five minutes — two in one trap, one in the other. We pulled off Swift Street at the entrance to East Woods, and released the reluctant trio in the glare of the headlights. I’ve never felt more furtive.

Turns out, we were actually breaking the law. We didn’t know it at the time, but Vermont Fish & Wildlife statutes prohibit moving raccoons from one part of the state to another. Baiting, trapping and killing are all OK, but relocation can be a criminal offense.

“The law came about to protect against rabies,” said Lt. Don Isabelle, Vermont’s district chief game warden, who could fine me $716 and take away my right to hunt, fish or trap for a year. “They don’t want people transporting raccoons that might be rabid into an area where they don’t have a problem with rabies.”

Hall confirmed the reason for the law — in Vermont, raccoons are the primary carrier of rabies — but he couldn’t remember the specifics of the Vermont statute. “Each state has different laws,” he said. From Concord, N.H., he oversees Vermont’s full-time rabies biologist, two rabies hotline answerers, and up to three seasonal fieldworkers who trap, vaccinate and release raccoons in the wild to prevent the spread of the disease, which is always fatal.

More bad news: “Relocated raccoons generally don’t do very well,” Hall informed me. “They are extremely territorial and aggressive with each other. If you move a raccoon to another area with an existing population, it doesn’t know where to find food. It’s got to whip every other raccoon in the area … They’ll kill each other.”

Over the course of the summer of 2011, Tim and I delivered 15 raccoons to meet that potential fate.

Local authorities recommend a simpler form of extermination. Burlington Deputy Police Chief Andi Higbee didn’t know it was illegal to move raccoons, either: “If the animal is actually breaking into your house, what are you going to do? You’ve got to take some action,” he said. “Could these things attack? I don’t think I want to find out.”

Higbee was the unlucky officer who got to respond last year when a woman slammed a dead raccoon against the front door of Burlington City Hall.

Isabelle was more specific: “The most humane way is to shoot it.” Asked about other options in a city that prohibits discharging weapons, he said, “Well, that’s a good question. I think they sell some kind of gas chambers that would basically put it to sleep.”

Tim might well have considered raccoon genocide when Rocky returned this summer. But after a couple of heated arguments, we went back to the old closed-door policy. ’Round midnight, the cat door slams shut, and Tito has two choices: in or out.

The silver lining: It makes us look forward to winter, when the raccoons “go into a torpor,” as Hall described their form of hibernation. And as long as we’re opening the door for Tito all night, we can see what he’s got in his mouth. That means he can’t bring live mice up to our bedroom, torture them and then let them make a run for the radiators. At least a dozen mice have vanished in our house since we moved in almost three years ago.

Guess we really love this cat.

Vermont Rabies Hotline: 800-4RABIES

Fish & Wildlife: 241-3727, 241-3716

General raccoon info: vtfishandwildlife.com/vtcritters/animalscfm?cat=mammals&species=Raccoon