Mary Warner of Berryville, Va., remembers Aug. 8, 1974 as the day of former President Nixon's resignation speech and as the day "my beloved German shepherd disappeared from the front yard."

Mrs. Warner said she is convinced that Copper, her pet of five years, was stolen. During the 2 1/2 years since that day, Mrs. Warner and others working with her have spent long hours trying to track dognapers who took Copper and other dogs.

Their theory is that there is an organized dognaping ring operating both in the Washington area and in the western part of Virginia. They said they base their contention on information they have received from dog dealers in Virginia and Pennsylvania, on records they have compiled showing that there are several hundred valuable purebred dogs missing in the two areas and on the fact that some of the stolen dogs have turned up in laboratories where they are used for research.

Mrs. Warner has formed a self-described "citizens vs. dog-napping group," called Action 81, which operates out of her home in Berryville, located about 65 miles west of Washington.

The name Action 81 derives from Interstate Rte. 81, which the group contends is the highway used by the suspected dognapers in this section of the country as they travel into Pennsylvania, where the dogs are then sold.

Action 81 acts as a communications network with other states, altering people to be on the outlook for stolen dogs, giving advice on how to keep dogs from being stolen, and working with law enforcement officials to track dognapers.

As Action 81 investigator Esther Boyd said, "We'd like to hang some of these dognapers."

Action 81 tries to help people like Peter V. Snyder of Alexandria, whose golden retriever was stolen last Friday afternoon while it was tied up outside Snyder's antique shop at 222 S. Washington St.

Though an Old Town attorney, whose offices are across the street, witnessed the theft and jotted down the last three digits of the license plate of the car the alleged dognaper was driving, police so far have been unsuccessful in finding Snyder's dog. Snyder said the animal called Cedric, is worth about $500.

"Few people see the thefts in front of their eyes and even fewer get license numbers," said Edna Cooke, executive director of the Alexandria animal shelter. Cooke said she believes that there has been a large amount of dognaping in Virginia for several years, and that the state's situation is "part of a large operation, highly organized . . . a very, very big, dirty operation."

Fay Brisk, a freelance writer who lives in Georgetown and who formerly worked with the White House consumer affairs office during the Kennedy-Johnson administrations, has been working or several years to help solve the dognaping problem in the Washington area.

She said interstate dognaping "is difficult to stop because it's hard to trace where the dogs are."

Part of the problem, she said, is that neither the U.S. Department of Agriculture, which is charged with enforcing the federal Animal Welfare Act, nor local-police forces have the money or the manpower to deal with the problem.

"The dognapers are much better organized than the police," Orisk said. "And, of course, the police have more important things to do. As for the (Agriculture Department), they are not dog-oriented. Their main job is livestock. They're not gangbusters . . ."

Alexandria Det. Sgt. Archie Hall said complaints about stolen dogs are "unusual" and thefts are hard to prove. He and other Alexandria police and Virginia State Police said they known of no dognaping ring operating in the state, despite Action 81's contention.

The antidognapers contend that the stolen pets are sold as pets to individuals out of state for a large profit, sold for dogfighting and sole to laboratories that use the animals for research.

Dale Schwindaman, the senior staff veterinarian on Agriculture's animal care staff said he doesn't believe the stolen animals are being used in laboratories.

Laboratories must keep identification records of animals they use, Schwindaman said, and Agriculture checks, albeit infrequently, to see that such records are kept. The Animal Welfare Act calls for humane treatment of warm-blooded animals used for such things as research and shows.

Schwindaman conceded that there has been some "so-called dognaping." He said the problem goes back a number of years.

He said he believes many of the stolen dogs are sold through newspaper advertisements as guard dogs.

The alleged dognapers apparently are mostly stealing Irish setters and German shepherds, or any large purebred dogs.

Mrs. Warner said she has either talked or written to about 10,000 people throughout the country who have either had their dogs stolen or are working to catch dognapers. Dognaping seems to be prevalent in the Washington area, northern Minnesota, North Carolina, the Chicago and Detroit area, southern West Virginia, Bristol, Tenn., and northwestern Virginia, she said.

According to Mrs. Warner's records, there were 343 dogs reported missing in a five-county area in western Virginia during the 18-month period ending in September, 1957. In January, 1976, 13 purebred dogs, such as labradors and golden retrievers, were taken from her neighbors' homes, all of whom live within three-to-four-mile area.