Dogs could be the saviour of global wine production threatened by disease

For more than a century, English Springer Spaniels have proven invaluable to huntsmen as loyal gun dogs that sniffed and flushed out their quarry.

But, now the animal’s acute sense of smell is to be harnessed to thwart the threat posed to the world’s vineyards by viruses and bugs.

A study has found the English Springer is adept at detecting mealybugs and leafroll that can decimate grape harvests producing some of the finest wines.

The pilot research project in California, which involved two English Springer Spaniels named Sauvi B and Zinny, discovered that using these working dogs was the cheapest way to efficiently scour acres of vineyards for potential infestations and contamination.

‘Winery dogs’

Sauvi B, along with a German Shorthaired Pointer named Cab, was able to detect the presence of vine mealybugs 97.3 per cent of the time, as well as rule out such an infection 100 per cent of the time. Zinny worked with a black Labrador named Malbec and was successfully able to detect the Leafroll 3 virus 93.4 per cent of the time.

Stephanie Bolton, the grower research and education director at Lodi Winegrape Commission, who conducted the tests, told a recent winemakers’ summit in San Luis Obispo that the use of so-called “winery dogs” could help protect vineyards from common forms of blight.

The vine mealybug, or planococcus ficus, is a pest that carries the Leafroll 3 virus which adversely affects a vine’s health and reduces crop size.

This mealybug spreads quickly because it regularly reproduces during a single season. It can be transported by birds, pruning shears and mechanical harvesting equipment, prompting intensive cleaning routines to help prevent its spread.

As reported by Wine Business, an online industry magazine, Ms Bolton told the winemakers’ summit: “The robust olfactory senses of canines can detect vine mealybugs and Leafroll 3 virus in nursery mother blocks and commercial vineyards at a level, which contributes to integrated pest management and is both economically feasible and scalable. This holds great potential for the sustainability of our industry.”

Referring to the problem caused by leafroll and mealybugs, she added: “We are not going to get ahead of this challenge if we keep planting infested and infected vines”.

As an incentive, the dogs would receive a reward after spotting infestations, leading to them viewing their work as a game. The animals’ detection rate is expected to improve over time as they become more efficient through practice.

The magazine said that Ms Bolton and her colleagues are now presenting their findings to leading members of the industry to try to establish how a “canine detector programme” could be rolled out.

The trial was funded with a $428,000 (£350,000) grant from the California Department of Pesticide Regulation. The dogs, who came from Hungary and Canada, were trained at Lisa Finke’s Canine Detection Services in Fresno.

Ms Bolton has been experimenting with dogs working in vineyards since 2020 after learning that canines were used to detect infections in the citrus growing industry.

Mealybugs are often first noticed as a fluffy white wax on leaves, but closer inspection typically reveals the presence of eggs underneath. Large populations of mealybugs can stunt growth and cause premature leaf drop.

Reduce reliance on pesticides

The Royal Horticultural Society website says several species of mealybug, including Pseudococcus calceolariae (Glasshouse mealybug), Pseudococcus longispinus (Longtailed mealybug), Planococcus citri (citrus mealybug) and Rhizoecus species (root mealybugs), occur in greenhouses or on houseplants within the UK.

Other research has established that dogs can also be used to sniff out other invasive species that can destroy vines, with dogs able to recognise the scent given off by powdery mildew. The use of dogs to detect such outbreaks can also help reduce the industry’s reliance on pesticides.

English Springer Spaniels have long been used as sniffer dogs by police and the military to detect explosives, drugs, and weapons. These gun dogs, traditionally used to flush out and retrieve game, are descended from the Norfolk and Shropshire spaniels of the mid-19th century, although the breed has since split into separate working and show lines. English Springers are also closely related to the Welsh Springer Spaniel and the English Cocker Spaniel.