WESTBROOK – Beauregard, a rambunctious Southern gentleman with liquid brown eyes, big floppy ears and wrinkly brow, journeyed 750 miles from Virginia to Westbrook in the dead of winter, looking for a new home.

Trixie, a sweetheart from middle Tennessee, followed a similar route, landing in a shelter in Kennebunk to begin a new phase in her young life.

Southern Maine has become fertile ground for stray or unwanted dogs from the rural South, part of a growing trend in which adoptable dogs are transported over increasingly long distances in hopes of hooking them up with potential owners.

“This is a really fundamental change in sheltering,” said Steve Jacobsen, executive director of the Animal Welfare Society in Kennebunk, where Trixie awaited adoption.

By some accounts, long-haul relocations got their start 15 years ago when North Shore Animal League America of Port Washington, N.Y., the world’s largest no-kill pet adoption and rescue organization, started transporting puppies from Virginia, Tennessee and the Carolinas to meet high demand in the New York City area.

“North Shore had basically pioneered the program,” said Perry Fina, explaining how it was put in place to deal with a shortage of puppies after spaying and neutering programs reduced the number of litters available for adoption.

The Oregon Humane Society launched its Second Chance Program in 2000 when it transferred more than 100 dogs from Hawaii. They were called “Aloha Dogs.” Since then, animals have been brought in from as far away as Mexico and Arizona.

“We don’t want an empty kennel,” Kathy Covey said. “If we have an open kennel, we want to make sure there’s a dog or a cat to fill it.”

Oregon Humane last year expanded its relocations to include cats, but they make up a small percentage of the total. Officials at most shelters say they have a chronic oversupply of felines and cannot imagine ever having to look far afield for more.

There are no figures on how many dogs are euthanized for lack of homes, but the Humane Society of the United States estimates that about half of the 6 million to 8 million dogs and cats placed in shelters each year are put down. Many others are abandoned or killed before they ever get to a shelter.

To improve the odds, humane officials are honing their skills at matching animals from areas where there are too many dogs with places where they’re in demand.

In Milwaukee, about 20 percent of pets awaiting adoptions at the Wisconsin Humane Society are transfers, many of which arrive from Indiana, Tennessee or Kentucky under a program launched last year by Petsmart Charities.

“We have more demand for good adoptable dogs than we have supply,” said Victoria Wellens, the agency’s executive director.

Petsmart’s Rescue Waggin’ has relocated nearly 8,000 dogs to animal refuges in Michigan and Wisconsin in its first year, said the program’s designer, Marlene Walsh of Oshkosh, Wis. A second Rescue Waggin’ is poised to go into service in California and organizers are looking into a third vehicle to serve the East Coast.

The specially designed vehicles can accommodate about 50 dogs and are outfitted with special lighting, ventilation, heating and cooling, running water and music. “It’s designed completely for the comfort and safety of the animals,” Walsh said.

Experts say dog shortages often reflect the success of aggressive spaying and neutering programs. Other contributing factors are strict leash laws and growing suburbanization, which discourage owners from letting their dogs run free.

Many of the long-haul dog adoptees in the Northeast and Midwest come from rural areas in the South, where fewer owners spay or neuter their dogs and shelters are nonexistent or lack the facilities to house inventories of stray or unwanted dogs.

Beauregard, a treeing Walker hound, arrived at the Animal Refuge League of Greater Portland in a van carrying six dogs from a shelter in Charlottesville, Va. The volunteer driver, Margaret Marsh, hopes to deliver dogs to Westbrook on a regular basis.

The Westbrook shelter has also received dogs from as far away as Ohio, Georgia and West Virginia, according to Susan Britt, its director.

Trixie, a 10-month-old Shar-Pei mix, landed at the Animal Welfare Society as part of its monthly shipment of 18 dogs from the High Forest Humane Society in Hohenwald, Tenn., co-founded by Suzanne Carr, former executive director of the shelter in Westbrook. Two volunteer drivers took turns at the wheel to make the 1,300-mile trip nonstop within a day. High Forest’s dogs also have gone to shelters in Salem, Mass., and Dover, N.H.

Carr, who moved to rural Tennessee a year and a half ago, said she had to do something after finding herself in an area where people routinely shoot or abandon unwanted animals. Hounds that won’t hunt are often let go.

Unfortunately, says Walsh, there’s a steady supply of unwanted dogs.

“Sadly, the majority of shelters need to ship out dogs because they haven’t solved the systemic problem in their communities of overpopulation,” she said.