Mark Barone was devastated when Santina, his dog of 21 years, passed away three years ago. His partner, Marina Dervan, thought it would be therapeutic to adopt a new dog, but Barone wasn’t ready yet.

That didn't keep Dervan from looking at adoptable shelter dogs though. But as she searched for a new canine companion, she stumbled upon a startling statistic: More than 5,000 shelter dogs are killed every day in the United States.

"I was horrified," Dervan said. "I did my research and found all these awful facts and images, and I kept sending the information to Mark. He said he couldn't look at it, but I told him we had to look at it. We had to figure out what we could do to help."

Two days later Barone said he had a vision for what they could do. He asked Dervan for the approximate number of animals killed in U.S. shelters each day and she told him: 5,500 dogs. The number is even higher for cats.

Barone's idea was ambitious: He’d paint portraits of 5,500 euthanized shelter dogs using photos from shelters from across the nation.

"I knew it had to be monumental to incite change, so I decided to put a face to that statistic,” Barone said. “I chose to focus on dogs because it was a number I could put my arms around and actually accomplish. Painting cats would’ve taken me seven years."

Barone has been working on the project for more than two years now, and he’s completed 3,700 paintings.

Most of the canines are painted on 1-foot by 1-foot panels, but 10 of the portraits are 8 feet by 8 feet. These massive paintings are reserved for those animals whose stories are especially poignant.

Mark Barone painting OreoOne of those portraits is dedicated to Oreo (pictured right), a dog who survived being thrown from a six-story building only to be euthanized in a shelter because the ASPCA determined she was too aggressive.

The dog's story inspired Oreo's Law, legislation that would make it illegal for a New York state shelter to kill an animal if a rescue group is willing to take the animal.

Now Oreo is memorialized alongside thousands of other shelter dogs — and one special cat named Porkchop whose tragic death inspired a petition to reform the Mobile County Animal Shelter. Each of Barone's pieces features the animal’s name and the date it was killed.

Barone and Dervan work on the volunteer project they’ve dubbed "An Act of Dog" seven days a week, 365 days a year. Barone paints 10 dogs a day, and when he's finished he says the project will be half the size of the Sistine Chapel.

When the paintings are complete, Dervan and Barone plan to partner with a city or philanthropist to build a permanent home for the work. They envision a nonprofit museum that raises awareness and funds to convert more shelters into no-kill facilities.

"This project is first and foremost for charity," Dervan said. "We want Mark’s art to inspire people and incite change. We want people to leave wanting to be part of the change with knowledge of how they can help, be that by donating money or taking action."

"I paint the dogs so they can live on and have their stories told and so we can help all animals — not just dogs," Barone said. "But there are all sorts of things you can do to help animals that aren’t to this scope. Get involved. Foster an animal. Every action can make a difference."

Take a look at some of Barone's paintings in the photos below.

An Act of Dog

Bailey, killed May 23, 2013

An Act of Dog

Breeze, killed Sept. 9, 2012

An Act of Dog

Bear, killed April 13, 2013

An Act of Dog

Harmony, killed Dec. 29, 2012

An Act of Dog

Sola, killed May 24, 2013

An Act of Dog

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Laura Moss writes about a variety of topics with a focus on animals, science, language and culture. But she mostly writes about cats.

Artist paints 5,500 shelter dogs -- the number killed in the U.S. each day
Mark Barone is immortalizing the dogs to put a face on the staggering statistic and encourage animal shelters to adopt no-kill policies.