The Calming Effect of Foster Care on Shelter Dogs
Millions of dogs enter the United States animal shelter system annually, and while many are eventually adopted, the shelter environment itself can be profoundly stressful for these animals. Factors like noise, inconsistent routines, and social isolation contribute to significant psychological strain. However, a new study suggests a relatively simple intervention – a temporary stay in a foster home – can dramatically reduce stress levels in shelter dogs, and that reuniting them with familiar canine companions upon their return to the shelter further enhances their well-being.
Researchers at Virginia Tech, in collaboration with Arizona State University and two animal shelters – one in Arizona and one in Virginia – investigated the impact of fostering on canine stress hormones and behavior. Their findings, published in PeerJ, demonstrate that even a one-week stay in a foster home leads to a substantial reduction in cortisol, a key indicator of stress, and an increase in resting time.
A Week Away Makes a Difference
Previous research had explored the benefits of shorter foster periods, typically lasting just a couple of nights. This study, however, focused on the effects of a full week in a home environment. Researchers meticulously tracked 84 shelter dogs over a 17-day period, encompassing five days in the shelter, seven days in foster care, and another five days back in the shelter. Data collection involved over 1,300 urine samples to measure cortisol levels, alongside activity monitors worn as collars to track rest and movement patterns.
The results were compelling. Cortisol levels decreased significantly during the foster stay, with the reduction being twice as large as that observed in studies involving shorter foster periods. Activity monitors revealed that dogs spent considerably more time resting while in foster homes. Importantly, the study found that cortisol levels did not spike when the dogs returned to the shelter, indicating that the foster experience didn’t create a rebound stress effect.
“While these improvements in dogs’ welfare were temporary in the foster home, dogs were no more stressed in the shelter following foster care as they were before it,” explains Lisa Gunter, an animal behavior and welfare expert at Virginia Tech and lead author of the study. “That’s encouraging because that’s often a concern. Instead, foster care is a chance for dogs to rest and recharge in a home.”
The Power of Familiarity: Kennelmates and Re-entry
Beyond the benefits of fostering itself, the study also explored the impact of social support during the re-entry phase. Researchers investigated whether dogs housed with familiar kennelmates experienced a smoother transition back into the shelter environment.
Prior to the foster stay, dogs sharing a kennel with a compatible companion showed no significant differences in stress or activity levels compared to those housed alone. However, after spending a week in foster care, those reunited with a familiar dog demonstrated increased resting time and reduced high-intensity activity compared to dogs housed alone or with unfamiliar companions.
“For dogs, familiar relationships provide stability—like a best friend in a stressful situation,” says Erica Feuerbacher, associate professor and co-principal investigator on the study. “Being kenneled with a known companion helped them settle faster and rest more easily.” Feuerbacher’s prior research has also indicated that cohousing familiar dogs can increase their chances of adoption.
Implications for Shelter Welfare and Adoption Rates
These findings build upon a growing body of work by Gunter and Feuerbacher aimed at enhancing the well-being and adoptability of shelter dogs. A previous study, encompassing 51 shelters and nearly 28,000 dogs, revealed that even short outings – lasting between one and four hours – increased a dog’s likelihood of adoption by a factor of five. Dogs who spent one or two nights in foster care were more than 14 times more likely to find permanent homes.
“Those adoptions weren’t usually by the foster families,” Gunter notes. “Instead, these dogs were out in the community, walking in a neighborhood, or being seen in a home on social media. That visibility makes a real difference.”
The combined evidence suggests that both foster stays and cohousing strategies can significantly improve the experiences of dogs within the shelter system and accelerate their path to adoption. These interventions are particularly appealing because they represent practical, low-cost solutions that shelters can implement immediately.
“We keep finding that when dogs leave the kennel and go into a home, they do better,” Gunter concludes. “These are the types of interventions shelters can use to improve the lives of dogs in their care.”
