On these dating sites, a passion for pets will help you find more than just puppy love.

Sites like PetsDating.com and YouMustLoveDogsDating.com have found a new niche as singles flock to computers and smartphones to find relationships, connecting dog owners to potential mates who enjoy long walks in the dog park and slobbery canine kisses as much as they do. Many of the sites encourage users to bring their dogs on first dates to break the ice and size up the canine chemistry.

Many dating sites cater to religious, cultural, and political preferences but won’t focus as heavily on interests like pets, music, or travel, said Karen North, a professor of social media at the University of Southern California’s Annenberg School of Journalism.

“If you find somebody with the same lifestyle passion, you don’t have to start out at square one,” North said.

When Joanie Pelzer signed up with a dog-friendly online dating service a few years ago, she was honest about her Chihuahua — he likes people more than other dogs, craves attention, steals food and can’t stand to ride in the backseat of a car.

Even a man who loved animals as much as she did couldn’t keep up with her dog’s quirks. On their first date, her Chihuahua, Hubbell, stole the man’s breakfast as they drove from New York City to Long Island. They had only one more date.

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Kris Rotonda, who founded YouMustLoveDogsDating.com, poses with his girlfriend Denise Fernandez and three of his four dogs. (Rebecca Brittain/Associated Press)

“I still wonder if Hubbell didn’t have something to do with that,” said Pelzer, 47, an actress who runs her own social media company and met the man on PetsDating.com.

Despite that setback, having a common interest such as pets can help the search for love.

“Having a theme that is … about one’s passion makes it feel like you are looking for a needle in a smaller and far more relevant and appealing haystack,” said Michal Ann Strahilevitz, a professor of marketing at Golden Gate University in San Francisco.

The founder of one of the dog-focused dating services, YouMustLoveDogsDating.com, agreed.

“Dogs on first dates are amazing icebreakers,” said Kris Rotonda, who started up the site last year that now has 2 million members. “You find out right off the bat how everyone in a relationship will fit in.”

But other veterans of the dating-service industry say focusing on a canine connection only adds an extra hurdle to finding love.

“When you consider how challenging it already is to find someone who offers what you are seeking in a romantic partner, and who seeks what you are offering, and where there is also mutual chemistry, and the timing is right … you have to wonder who in their right mind would want to make it even more challenging by insisting on canine chemistry,” said Trish McDermott, who spent 10 years as the dating expert and spokeswoman for Match.com.

McDermott points out that new love is hard enough to foster, without any added issues.

“To squeeze doggie behavior under the first date microscope and to analyze every little wag, nip or bark as further commentary on compatibility is just another way to uncover the fatal flaw of an otherwise potential romance,” added McDermott, who now works for OneGoodLove.com, a gay, lesbian, and bisexual matchmaking service.

McDermott’s concerns won’t change Pelzer’s plans to return to PetsDating.com. She remembers unpleasant run-ins with dates from sites that don’t cater to animal lovers — once a man nudged her pooch off the couch.

“That was the last time we were together,” Pelzer said. “You don’t do that to my dog.”