John T. Donaldson, 86, an artist whose realistic watercolor and oil paintings captured the grace, beauty and athletic prowess of bluetick coonhounds, border collies, Jack Russell terriers, German shorthaired pointers and other sporting dogs, died June 5 at his home in Falls Church. He had atherosclerosis and chronic obstructive pulmonary disease.

In 1970, Mr. Donaldson owned a commercial art studio and was painting pictures, of barns primarily, when a friend urged him to do an oil portrait of his champion shooting dog. "After a few months, the painting was ready, and one thing led to another," Mr. Donaldson told Canine Images magazine in 1999. "Eventually, I decided I'd much rather do this type of work and only kept on a few commercial clients."

He was soon painting about 20 commissioned dog portraits annually, either head studies or dogs in hunting or field trial scenes. Beginning in 1973, he painted the winner of the Top Bird Dog Award, presented annually by the Ralston Purina Co., and soon began painting the winners for numerous other hunting dog competitions.

"John Donaldson knows, understands and loves dogs, going back to his first one, an Irish setter, when he was a boy," said Keith Severin, quoted in American Field: The Sportsman's Newspaper of America. Severin curated a 1991 retrospective of Mr. Donaldson's bird dog paintings for the American Kennel Club Museum of the Dog near St. Louis.

Mr. Donaldson was born in Springfield, Mass., and grew up in White Plains, N.Y. His first experience around a bird dog came after he received an Irish setter puppy when he was 13. A few years later, a neighbor invited him to go pheasant hunting with a springer spaniel. "I couldn't believe what I saw," he told Canine Images.

While in high school in White Plains, he attended the Art Student's League in New York City, where he studied anatomy with the renowned George Bridgman. He went on to study art and illustration for three years at the Pratt Institute in Brooklyn. In the years before World War II, he drew comic strips for Dell Publishing Co. and worked for General Motors and Remington Arms.

He served in the Army Air Corps during the war, with the 8th Air Force in England and France, and then moved to the Washington area in 1944. From 1944 to 1950, he worked for the Naval Gun Factory, for Reed Research, as art director, and for Ted Christenson Associates, also as art director. From 1950 to 1960, he was a partner in Design Directors before launching his career as a self-employed commercial artist. He also taught art at Montgomery College in Rockville.

Mr. Donaldson was a 52-year resident of Montgomery County. He was a Boy Scout master in Brookmont, a member and president of the Chevy Chase chapter of the Izaak Walton League and a member of the Potomac Art League and St. Francis Episcopal Church in Potomac. He had lived in Potomac from 1960 to 1996, when he moved to Falls Church.

"I'm one of those lucky people," he told Canine Images. "I know many people working at things they don't really like to get a paycheck." He worked steadily until 2001, when a detached retina forced him to lay down his brushes.

His marriage to Ann W. Donaldson ended in divorce.

Survivors include three daughters, Petie Donaldson Bonbrest of Falls Church, Sally Donaldson Tomlin of Springfield, Va., and Kate Donaldson Sarfaty of Maidens, Va.; two granddaughters; and five great-grandchildren.