When Cindi Hindman started fostering Oscar, a German shepherd and Labrador retriever mix puppy in September, he acted anxious and hypervigilant. He paced around the house, unable to settle and showed little interest in affection.

Less than 48 hours after being in her Frederick, Md., home, Oscar was playing with toys, snuggling on the couch and sleeping peacefully in his crate.

“It was very rewarding to see how quickly a little love and understanding brought him around,” Ms. Hindman said. “It’s amazing to me how these dogs that come from shelters are so sweet and loving and want to please.”

Oscar is the fourth dog Ms. Hindman has fostered during the coronavirus pandemic. Molly, an English pointer mix; a lab mix puppy named Sully; and Rocky, a black Labrador retriever, have also bunked with Ms. Hindman temporarily before being adopted into their "fur-ever" homes.

“I’d thought about fostering before, but it was hard to find the time and make the commitment,” she told Medical Daily. “The pandemic gave me the opportunity to volunteer for a local rescue.”

The pandemic has triggered record-breaking interest in fostering shelter animals.

Best Friends Animal Society, the largest no-kill animal sanctuary in the United States, has experienced unprecedented interest in fostering. Between March and May, their facility in Salt Lake City, Utah, placed 670 pets into foster homes, compared with just 209 during the same period in 2019; and 145 pets from their Atlanta facility went to foster homes during the quarantine, compared with 40 pets last year.

“In times of crisis, people look for comfort and ways to help,” said Julie Castle, chief executive officer for Best Friends Animal Society. “Fostering helps bring comfort to people and helps local shelters by reducing the number of pets they need to take care of on a daily basis.”

The shelter environment can be stressful for dogs and cats. Fostering helps animals that are frightened in shelters. Injured or ill animals that need extra care benefit from a home environment, while foster families help save lives when shelters are full.

Foster families benefit, too. Companion animals provide myriad health benefits, ranging from decreased blood pressure and cholesterol to less feelings of loneliness and more opportunities for exercise, according to the U.S. Centers for Disease Control and Prevention.

The impact has been especially profound during the pandemic. New research found that sharing a home with a pet provided a buffer against negative psychological effects of the pandemic-related lockdown.

“The companionship of pets helps people to feel calmer and more secure when the news from the outside world is distressing,” Ms. Castle said.

She hopes the effects will be long-lasting. The number of animal adoptions are also way up during COVID-19. Foster families have worked hard to introduce their foster pets to potential adopters through social media and virtual meet-and-greet events to ensure adoptable pets aren’t returned to shelters.

For Ms. Hindman, who spends more time playing in the yard and walking around her neighborhood with her four-legged companions, fostering has been a worthwhile way to spend her time in quarantine during COVID-19.

“It’s been very gratifying for me to see how adaptable these dogs are,” she said. “There’s [the] satisfaction of knowing I’ve done something good for the dogs, [and] feeling a sense of purpose has been very good for my mental health.”