Cape-born and raised with at least a couple of generations of family there before him, Behrens, 26, got the idea while on a trip to San Francisco, where bike couriers were flying up and down the city's hilly streets.
"I thought, 'Man, that looks like fun. I'd like to do that for a living,' " said Behrens, who does not own a car and whose tattoos include a bike tire on his right ankle.
He let the idea germinate for a while. Then he told his friend Matt Reeves.
"He said, 'Dude, that would work.' "
On April 22, 2013 - Earth Day - Cape Couriers was born. No fossil fuels. No fumes. Just bikes.
This summer, Reeves is tending bar at the Mad Batter, but Behrens has been joined by Pete Hardy, 30, a cyclist and stay-at-home father interested in a little extra cash.
The couriers' service area includes Cape May, Cape May Point, West Cape May, and Lower Township, which they have divided into zones. Their fees range from $5 for service within one zone, $7 for two zones, $9 for three zones, and $12 for four zones.
They have put the word out via social media, including regular posts to Facebook; fliers; business cards; and word of mouth.
Calls come in from locals as well as tourists:
Bartenders who need a pack of smokes, office workers who can't spare time to get lunch, hungry lifeguards who can't leave their posts. Even a post office run.
One fine-dining restaurant called in an order for two large bottles of cabernet sauvignon and a bottle of triple sec, presumably for cooking, and three six-packs of pale ale, presumably for the staff after closing, Behrens thought.
Last year, Behrens and Reeves stopped at the Bliss ice creamery in Cape May to drop off a business card. It turned out a freezer had broken down, and the owner needed five gallons of ice cream brought from her West Cape May store on that hot summer day.
"We made it in three minutes," Behrens said.
Some jobs are big, like the $85 order the Accent on Beauty salon needed brought from Big Wave Burrito. Some are small, like the three slices of pizza and three drinks a family recently wanted delivered to the beach.
Diane Wieland, director of Cape May's tourism department, said some eateries make beach deliveries, but she hadn't heard of another Shore courier service quite like this one.
"They're providing the utmost in service to vacationers," Wieland said.
Being a bike courier comes with occupational hazards. Once Behrens was en route to pick up bobby pins and hair spray for a bridal party when an unfortunate encounter with a trolley, a pack of cyclists pedaling the wrong way, and an awkwardly placed SUV made him stop short, hit a curb, and fly off the bike.
"I was OK," he said. "I just cut my ankle.'
No one is getting rich yet. Behrens rides six days a week and works three nights at Sunset Liquors. His old job at a local surf shop paid more than he makes as a bike courier.
Some days, the phone doesn't ring at all.
"It can be a little demeaning," he acknowledged. "You have to take the bad with the good."
But Behrens, who spent a year at a college in Newark studying architecture but decided he missed his Cape May life, found his current gig has its perks.
"Everybody's been 100 percent supportive in town," he said.
This year, seven local businesses have become sponsors; Behrens and Hardy have their names on their jerseys. And word-of-mouth advertising is up.
"I'm just happy I'm outside, riding a bike and interacting with people. Riding a bike is my passion," Behrens said.
He likes the freedom of making his own choices, planning routes on the fly on his fixed-gear Raleigh Rush Hour Pro.
"It's the exhilaration I strive for," he said. Plus, he gets to run into family and friends. "And I'm my own boss. I don't have to listen to anybody."
Except, of course, the caller with a lunch order ready to go.
Cape Couriers' hours are 9 a.m. to 8 p.m. Friday through Sunday and 9 a.m. to 6 p.m. Tuesday through Thursday. It is closed Monday. The phone number is 609-827-2803.