There is a dog in Vietnam that climbs trees, swims with webbed feet, and carries a strip of backward-growing hair down its spine. Most people who see a photo assume it is a small Thai Ridgeback. But a 2019 study by Quan and colleagues, measuring 175 adult dogs, found the breed differs from both the Thai Ridgeback and the Rhodesian Ridgeback in height and weight. The three ridged breeds look related. The evidence says they are not.
Phu Quoc Ridgeback at a glance
- Origin Phu Quoc island, Kien Giang Province, Vietnam
- Height Males roughly 19 to 21½ inches
- Weight 33 to 44 pounds
- Coat Short, single layer
- Registry Roughly 800 certified purebreds
A landrace, shaped by an island
Nobody designed this dog. It is a landrace, shaped by geography rather than a studbook. Dogs lived alongside island fishermen and farmers, hunted to supplement thin rations, and guarded homes. Water separated them from mainland dogs for generations, and that isolation is why the breed exists as something recognizable.
The ridge must cover at least two-thirds of the back to meet the Vietnam Kennel Association standard, and the feet carry visible webbing between the toes, unusual in dogs and directly useful in water.
Yes, they climb trees
Owners find these dogs on fences, kennel roofs and in trees. A 400-meter obstacle course at the island’s Thanh Nga conservation center puts them through tall grass, tree climbing, tunnels and open water. Historically they tracked in packs of three to six, followed fresh and cold trails, and hunted prey from rodents and fish up to deer. None of that was bred out, because for most of their history nobody was breeding them on purpose.
Legends and early records
Legend holds that in the 18th century, four Phu Quoc dogs protected Nguyen Anh, who became Emperor Gia Long, while he fled the Tay Son army. After taking the throne, he included the dogs among those he honored, with a title translating roughly to Great Generals of Divine Dogs.
Outside records begin with the French. Fernand Doceul, a colonial official in southern Vietnam in the 1890s, first brought the dogs to European attention, and two lived at the Jardin d’Acclimatation in Paris. French writers warned the dog would disappear without intervention.
They were nearly right. War, neglect and interbreeding pushed the purebred population toward collapse through the late 20th century. The island’s isolation and a small group of breeders who began rebuilding in the 1980s saved it.
Surprising genetics
Analysis of mitochondrial DNA from 77 Phu Quoc Ridgebacks, against 30 village dogs as controls, found high diversity and an unusual frequency of the rare haplogroup E, with about 17 percent carrying E1. Not one control dog carried it. Follow-up sequencing placed those dogs in the same clade as Korea’s Pungsan dog.
The mutation behind the ridge, identified in 2007, is also associated with dermoid sinus, a congenital skin defect that can reach the spinal canal and turn fatal if infected.
Why it’s still so rare
A 2017 Vietnam Kennel Association census counted about 3,700 dogs, but that included village dogs and undocumented offspring; the certified registry has since been tightened to roughly 800. The FCI still doesn’t recognize the breed. In 2011, two dogs traveled to the World Dog Show in Paris and couldn’t compete for top honors for that reason. The larger risk now is dilution, with dogs crossbred or mislabeled to meet demand.
Who it suits
These are still semi-wild hunting dogs with high energy, deep prey drive and a talent for climbing out of anything: a poor match for a small apartment, or an owner who wanted a rare dog more than a working one.
