Studies have shown that people benefit from having pets. Our pets keep us mentally and physically active and lower stress levels and blood pressure. These health benefits are especially valuable in older age.

Unfortunately, many seniors who might benefit most from owning pets often feel reluctant to take on the responsibility. Some may be too preoccupied with their own medical concerns to worry about nurturing an animal. Others may be uncertain about the immediate future or just wish to keep life simple.

One Youville House resident found herself in a similar situation months ago when she first moved to Youville. Tenny wasn't sure how long she'd stay at Youville and wanted to keep her life simple. At the same time, she missed having a dog and wanted to stay involved with one in some way. For a while she volunteered as a dog-walker at the MSPCA in Boston, but found the experience unfulfilling.

"A lot of the dogs staying at the MSPCA shelter had serious issues," she recalls. "Out of the 10 dogs that I walked, only one of them was even walkable -- the rest were too unruly."

When friends needed someone to look after their spaniel for a few weeks, Tenny was happy to volunteer her apartment and caretaking services. During this period, she rediscovered the benefits of living with a dog: more exercise, more time spent out of her apartment, and constant companionship. Because the arrangement was temporary, she was free to enjoy the company of her houseguest without worrying about the long-term responsibility.

After returning the spaniel to her friends, Tenny began looking into dog foster programs. Her search led to a young, energetic black puppy with deep, imploring eyes and a distinguished white terrier-like beard.

"That was Travis," she says. "When I saw him I knew I wanted to take him." She filled out an application and submitted it to the rescue organization. After a short wait she was approved as Travis' foster caregiver.

Retired seniors are often ideal animal foster caregiver. Because they're around during the day and don't have to worry about work, they can devote more energy and attention to training and caring for the animal.

"There is some risk involved," Tenny admits. "Some animals may not be well-behaved. You're there to give them a home and help socialize them so that they'll be ready for adoption. If there's a problem or you find you don't get along, you can always return the animal to the shelter." Like the majority of dogs in New England, Travis is not native to the area. He was brought here from a shelter in the south, where there's an epidemic of homeless dogs and overcrowded shelters.

It's estimated that 90 percent of domestic dogs in New England are originally from outside of the region. While New England dog owners tend to neuter and spay their animals, dogs proliferate freely in other regions of the country. Millions of animals face euthanization each year in order to make room for other animals in overcrowded shelters. A network of rescue workers takes the dogs from the shelters and drives them up north for adoption.

Joanne Bourbeau, New England regional director of the U.S. Humane Society, has said that the growing number of adopted animals is a matter of "supply and demand. Southern shelters are supplying the need, we have the demand."

Before adoption, foster caregiver are needed to provide the animals with a temporary home. Foster applicants can specify what kind of animal they want: dog or a cat, adult or puppy, high or low-energy, etc. Shelters often pay for expenses related to caring for the animals -- such as food, toys, training, and veterinary care.

Senior foster caregiver are likely to experience a boost in activity and energy. Taking responsibility for another creature's well-being causes an upsurge in oxytocin, a hormone connected with feelings of belonging and well-being. Oxytocin makes us less stressed and happier. The sense of connectedness to another living being can contribute to a healthier body and brain. The routine of feeding, walking and interacting with pets keeps us in shape while also engaging the brain.

The duration of foster care varies depending on the needs of the animal. One animal may need time to become used to living in a home with human beings. Other animals may be too young, in need of training, recovering from illness or injury, or simply in need of a place to stay while waiting for the right family.

With Travis, foster care only lasted a month or so before he was ready for adoption. And it was his foster caregiver, Tenny herself, who adopted him. Though no longer technically a foster caregiver, she believes that others can benefit from fostering animals. "You're doing a good thing for them," she says. "And most of the time, they're doing a good thing for you."

Adam Johnson writes for Youville Assisted Living Residences, member of Covenant Health Systems, a Catholic, multi-institutional health and elder care organization serving New England. See www.youvilleassistedliving.org.