Frankie, a blue-eyed Catahoula Leopard dog, was just a few weeks old when he was found abandoned on the side of a Charlotte street — one of more than 6 million animals dumped across the United States each year. Weighing only 7 pounds and riddled with hookworms, he was taken in by Angels to the Animals, a rescue group based in Denver, North Carolina that hoped to give him a shot at survival.

But while rescuers are doing everything they can to save Frankie from becoming one of 920,000 animals euthanized annually, there’s an obstacle standing in the way of his adoption. Frankie is deaf, a common reason dogs are discarded and one that makes placement significantly harder.

“It’s difficult to find somebody who wants to take in a deaf dog,” said Melissa Lang, president of Angels to the Animals. “He can’t hear ‘No,’ he can’t hear ‘Frankie, stop.’ ”

North Carolina ranks second in the nation for the number of animals euthanized in shelters, a crisis fueled by chronic overcrowding and staffing shortages. Recently, available kennel space at Charlotte-Mecklenburg Animal Care and Control’s facilities hit a record low. In response, the shelter waived adoption fees in hopes of placing 250 animals.

“This is as serious as it gets,” the organization wrote in a Facebook post, noting that dozens of dogs “may not have a tomorrow.”

Advocates say dogs like Frankie, those with special needs, face even steeper odds. Many shelters lack the training or resources to care for deaf animals, leaving them more vulnerable to euthanasia.

“They have to euthanize them because they need the space,” Lang said. “It’s just not a good long-term solution for a hearing or non-hearing dog.”

Still, Lang said more facilities are beginning to specialize in caring for animals with disabilities. Among them is Virginia-based Deaf Dogs Rock, which partners with rescues across the country to pull deaf dogs from kill shelters before it’s too late.

Since its founding in 2012, Deaf Dogs Rock has helped thousands of deaf dogs find homes and provided training resources to adoptive families. The nonprofit also works to educate shelters — many of which automatically euthanized deaf dogs until just the past decade.

“If you had a deaf puppy, it had to be destroyed,” founder Christina Lee said. “Think about the message that sends out to everybody.”

Frankie, however, was lucky. He never entered the shelter system. Emaciated, dehydrated and infested with hookworms, the tiny puppy came to Lang’s attention through word of mouth. She immediately arranged for emergency medical care.

Now, even as 5-month-old Frankie has recovered and grown stronger, Lang is still searching for his permanent home. If he isn’t adopted by the end of the month, Angels to the Animals may have no choice but to board him in a kennel until a family steps forward.

Still, experts say there is hope. Some deaf individuals actively seek out deaf dogs, drawn by the potential for a deeper bond and a desire to offer them the care they deserve. With more rescues catering to special needs opening across the country, these adopters can now turn directly to organizations that specialize in dogs with disabilities.

“Every day I get emails from ... deaf community members looking for deaf dogs,” Lee said. “They’re a very tight-knit culture and I think they can relate to a deaf dog.”

But identifying deafness isn’t always immediate. In many cases, hearing loss in puppies goes unnoticed for weeks or even months. That was true for Frankie, until his first foster family realized he didn’t respond to his name or react when objects fell out of sight.

Lang eventually conducted her own test, confirming that Frankie is deaf. Once a diagnosis is made, she said, the chances of adoption often drop, especially at rescues that aren’t known for working with animals who have special needs.

Even so, Lang eventually found a family who wanted Frankie, a couple willing to adjust their training and lifestyle to meet his needs.

Sarah Ziarko had long been interested in adopting a deaf dog, and when her husband, Andrew Boblit, spotted Frankie’s photo online, he didn’t hesitate to reach out.

They brought Frankie to their home in Iron Station, North Carolina, captivated by his boundless energy and charmed by his bright eyes. They laughed at Frankie’s tendency to bark at rocks and were patient when it took extra effort to get his attention.

“Even though he can’t hear, he observes his surroundings and uses other senses more,” Boblit said.

When Lang offered a complimentary session with a trainer who specializes in American Sign Language, Boblit and Ziarko were eager to get started. But after introducing Frankie to their older dog, Bennington, the couple realized that he wasn’t the right fit for their family.

“Frankie can’t hear our dog bark at him or indicate that he doesn’t want to play,” Ziarko said.

Lang now hopes to find Frankie a new home. In the meantime, Ziarko and Boblit are continuing his sign language training using videos and written guides.

So far, they say, it’s working. Frankie picked up the sign for “sit” and now responds without needing a treat.

“It’s a little more difficult because you have to visually get their attention as opposed to just calling their name,” Boblit said. “But I don’t feel like it’s any more energy or any more effort with a deaf dog than it is with a normal dog.”

Traditional dog training often pairs a hand gesture with a verbal cue, followed by a treat to reward and reinforce the behavior. But for deaf dogs, the verbal cue is removed entirely, and the dog relies solely on visual signals.

Lee is now fostering her 10th deaf dog, and she has come to view deafness as a kind of “natural superpower.” Her dogs, she said, are often more attuned to subtle movements and emotional cues than their hearing counterparts.

“We say they’re like potato chips,” she said. “You can’t just have one.”

On a recent evening, Frankie raced through the backyard of his foster home as Ziarko introduced a few new signs. He paused, alert and eager, then leapt up to celebrate with his foster parents each time he got it right.

“It’s a full-time job, a full-time responsibility to take care of a dog,” Boblit said. “It’s just personal preference if you’re willing to love a deaf dog like you would a hearing dog.”