A Petaluma-based nonprofit is leading a nationwide information and fundraising effort for animal shelters taking care of senior dogs in the fifth annual Saving Senior Dogs Week.

Lily’s Legacy Senior Dog Sanctuary in Petaluma is collaborating with senior dog rescues across the country to present the fifth annual Saving Senior Dogs Week — a week-long national social media campaign that brings awareness of the struggles of homeless senior dogs all over the country and the joys of adopting them.

The campaign, which began Monday and runs through Sunday, is also being done to raise funds for the Saving Senior Dogs USA nationwide network of senior dog rescues.

On Saving Senior Dogs Week, partnering senior dog rescues share hundreds of rescue and adoption stories on their social media sites to highlight the work they do. The dogs featured in these stories are called Saving Senior Dogs Week “Ambassadogs.”

Aside from Lily’s Legacy, local Bay Area participating shelters include Muttville Senior Dog Rescue in San Francisco, Peace of Mind Dog Rescue in Pacific Grove, and Tails of Gray Senior Dog Rescue in Livermore.

The Saving Senior Dogs Week network of partnering senior dog rescues has grown over the last five years and now includes around 37 senior dog rescues that are located all across the country.

Thousands of dogs euthanized

According to the American Society for the Prevention of Cruelty to Animals, approximately 390,000 shelter dogs are euthanized each year in the United States.

Senior dogs are least likely to be rescued or adopted from shelters and are most at risk of being euthanized, according to Saving Senior Dogs USA.

Although there are an estimated 4,400 animal rescue organizations nationwide, less than 1.5 percent of them are dedicated exclusively to rescuing, rehabilitating and rehoming senior dogs, the animal shelter group added.

Over the past decade, the number of US households with a dog older than 7 years of age has increased from 42 percent to 52 percent, Saving Senior Dogs USA said.

More information about Saving Senior Dogs Week, where to make donations and adopt senior dogs is available at www.savingseniordogsusa.org.