The Nose Knows

“Man’s best friend.” As long as history has been recorded (indeed, dating back to early cave paintings), dogs have accompanied and assisted humanity. We’ve taught them to hunt with us, herd our livestock and protect our loved ones. In recent generations, dogs have been bred and trained to see, hear and do for those who can’t. Marin County is home to the venerable Guide Dogs for the Blind organization, and service dogs now open doors, turn on lights, answer telephones and perform a host of other physical activities for individuals with disabilities.

Dogs have also been trained to use their keen sense of smell to aid in the detection of everything from cancer to illegal drugs to pirated DVDs. Now Santa Rosa’s Assistance Dog Institute (ADI) is honing that ability to benefit a key component of our local economy: the vineyards. ADI is now in its second year of a two-year research project aimed at training dogs to sniff out the pheromone of the female vine mealybug, a nasty and hard-to-detect species with the potential to decimate entire crops.

“We’ve long known that a dog’s sense of smell is much more developed than ours,” explains Jorjan Powers, community and public relations director for ADI. “But it’s only recently that we’ve really begun exploring how useful that can be.

“We’re having a lot of success [with the mealybug project] right now. The dogs are excited; they want to do it. Dogs love to help people—and, of course, what better job could there be for a dog than running through a vineyard?”

Know the enemy

When ADI founder Dr. Bonita “Bonnie” Bergen first considered using dogs for vineyard pest detection, she intended to target the glassy-winged sharpshooter, which at the time was garnering headlines for its destructive habits. But a conversation with Sonoma County vineyard owner and friend Saralee Kunde pointed her instead toward the vine mealybug.

“I’d been hearing about the glassy-winged sharpshooter and realized they had to be dealt with. I went to Saralee, whom I’d known for years, to talk with her about my idea,” remembers Bergin. “She was very enthusiastic about the concept but told me the biggest danger was really the vine mealybug. She put me in touch with Katey Taylor, who was heading up a study group for the Carneros vineyards; we worked together to design the project.”

“Our group spearheaded the first year of fundraising efforts,” confirms Kari Flores, viticulture technician at Domaine Chandon and Newton Vineyard and a member of the Vine Mealybug Work Group (formerly the Carneros Mealybug Working Group). “We solicited our friends, neighbors and relatives—everyone. We also formed an advisory committee to help Bonnie understand how we scout the vineyards for pests.”

A native of the Mediterranean, the vine mealybug was first discovered in California’s Coachella Valley in 1994. By 1998, it could be found in vineyards across the south end of the San Joaquin Valley. Populations have since been found in El Dorado, Monterey, Madera, Sacramento, San Luis Obispo, Stanislaus, Sonoma and Napa county vineyards.

Locally, the first infestations were found in Carneros in 2002 and 2003, but consensus is the bug is now spreading from those original sites. The Napa Valley Agricultural Commissioner has discovered vine mealybugs in 37 different vineyard locations across the county. Sonoma County doesn’t have the same aggressive trapping program in place, so no hard numbers are available (although many growers are trapping for the pest on their own). But, says Flores, “vine mealybugs don’t care where the county lines start and stop.”

Vine mealybugs are related to (but considered a much more serious threat than) grape mealybugs, obscure mealybugs and longtailed mealybugs. The latter three species are often grouped together as “the grape mealybug complex” and, being native, are more susceptible to a variety of natural control methods. All mealybugs have needle-like mouthparts called stylets that they use like a straw to suck internal plant material; they then expel a sticky, waxy substance called “honeydew,” which can not only attract other pests (including ants, which feed off the honeydew and therefore defend the mealybugs against some natural insect predators) but is also an ideal breeding ground for sooty molds and, if allowed to build up, can actually smother a plant and render its fruit useless. Mealybugs can also carry grape viruses.

Mealybugs (of all varieties) can also live on any part of the plant—roots, stem, leaves, fruit clusters and under the bark—making them nearly impossible to detect without close inspection of each individual plant. And even then, they’re hard to spot. Ants, for example, can mask mealybug presence by eating the honeydew and therefore removing any easily visible evidence until it’s too late.

The female vine mealybug is unable to fly, so she must be introduced to a vineyard by other means. Many of the early California infestations were traced back to young vines from a single nursery in Kern County. But these tiny insects (an adult female is only one-eighth of an inch long while an adult male is nearly microscopic) can easily be carried by unsuspecting humans on clothing or farming equipment and by the forces of nature. Research has also shown vine mealybugs can survive the fermentation process and can be transported in grape pomace that some wineries and growers spread in their vineyards.

“Because of the way the bugs can be transferred, they won’t just start at the edge of a vineyard and work their way in,” explains Powers. “A vine somewhere in the middle can be the first infested. And since [the bugs are] microscopic, there’s no way of telling until the damage has been done. That’s why the dogs are so beneficial; they can detect the scent in miniscule amounts.”

“The most alarming moment in this growing infestation was when we realized the bugs were being transferred not only by boots and tractors, but by birds and wind—things we had no control over,” confirms Jennifer Kopp, executive director of the Napa Valley Grapegrowers Association (NVG). “This realization came about the same time ADI contacted us. The dogs were a much needed ray of hope.”

“The idea was well received from the start,” agrees Flores. “Most growers are looking for wways to mitigate chemical pesticide use—especially the organophosphate-class of pesticides needed to combat vine mealybug. The timing was right, and it just struck a chord.”

Helping dogs help people

Let’s back up for a minute. Before she envisioned dogs rescuing grapevines from invisible pests, Bergin envisioned dogs rescuing people from lives of dependence.

In the mid-1970s, she founded Canine Companions for Independence (CCI) to breed and train assistance dogs. For 17 years, she built the service dog concept, placed dogs with individuals, monitored their progress and trained breeders and handlers to establish similar facilities across the country. Today, CCI boasts more than 1,200 active graduate teams nationwide (with more than 200 on the waiting list) and has regional offices in California, Florida, Ohio, New York, Illinois and Colorado.

By 1991, though, Bergin realized CCI’s programs would never keep up with the growing demand for assistance dogs. The answer, she decided, was to start training humans—not dogs—for maximum impact. She founded the Assistance Dog Institute (ADI), an educational and research institution dedicated to teaching and researching ways to (as its slogan says) “help dogs help people.”
ADI offers college degree programs (associate, bachelor and master of science) in two fields: Human-Canine Life Sciences and Assistance Dog Education. It also offers several professional certificate courses that can be taken for continuing education credits. These include seminars for both dog trainers and human partners, but also courses in people management and teacher or parent training (which apply the same motivational techniques used to train dogs to human interactions) and a seminar that focuses on the social therapy applications of service dog work.

“The service dogs are what most people come here for,” admits Powers, who is enrolled in the Institute’s master’s degree program, “but we also have Human-Canine Life Sciences, which is more broad-based. There are so many applications for using dogs in our society.

“We have a big social therapy program, too. We take dogs out to not only visit patients in hospitals and convalescent homes, but also to respond to police and sheriff’s calls for trauma [or violent] situations. In a lot of those situations, the victim can’t immediately talk about it. When they bring in a dog team—especially with children—it calms them. They can pet the dog and talk to the dog as opposed to a human counselor they don’t know and may not trust. It facilitates communication.”

Dog years

Obviously, Bergin spends a lot of time thinking of ways to foster the bond between mankind and canines. So when she began hearing about insects threatening our vines, she took action. “I came up with a formal training plan that spelled out each step of the progression and gave a way to measure our levels of success,” she says.

In summer 2005, ADI officially began a two-year research project that combines elements of the Institute’s research into early puppy cognitive development with a unique training process that merges scent detection training with search-and-rescue techniques. In the first year, ADI met its project goals, which included:

•    Developing successful vine mealybug odorant detection methods with both synthetic and actual pheromone;

•    Researching the best methods for dogs to work in vineyards efficiently, including continuous assessment of wind patterns and field conditions;

•    Training more than 15 puppies in early scent detection work;

•    Training six dogs in more advanced skills and early field work;

•    Breeding a special litter of scent detection puppies; and

•    Determining the required skill set of scent detection dog handlers.

Finding just the right dogs seems to be key. ADI service dogs are bred to be “low arousal.” Their mellow demeanor helps them integrate smoothly into the bustling everyday world in which their human partners function. When it came to vine mealybugs, however, it became apparent that a more assertive temperament was needed.

“As we went forward into the project, the vineyard group helped us change and refine our requirements. They were especially helpful in structuring the ways the dogs needed to go down the rows and identify the infested vines,” says Bergin.

“Our original plan was to use our service dogs, on-leash, walking the vineyard rows with a vineyard owner or field worker who would care for the dog year-round. Service dogs need a strong bond with their handler. But what the vineyard group decided was  it wanted the dogs to be more assertive in their searches. The group wanted dogs that could work off-leash, which required a huge shift in our training. That’s when we turned to search-and-rescue techniques and more driven dogs.”

Bergin turned to a friend with experience in search-and-rescue training for advice. Working with retired firefighter and paramedic Bud Souza (an ADI faculty member and FEMA/OES certified canine specialist whose golden retriever, Kane, is the youngest dog ever to earn FEMA Type 2 certification), ADI has bred two retriever litters for the vine mealybug project.

“[The dogs] need to be chasing and moving independently, thinking on their feet,” explains Powers.

“Search-and-rescue dogs are a much better fit. Bud Souza has had great ideas about how to train the dogs and send them off [to search independently], for example, using whistles to call the dogs back from a greater distance.”

The puppies are first introduced to the pheromone of the female vine mealybug in the whelping box when a synthesized version is put on the mother prior to nursing. This positive association training continues as the dogs mature, with treats and playtime taking over when the pups are weaned, until the scent is ingrained in the dog’s memory and the dog develops a strong desire to seek it out whenever it’s present. The dogs are also taught an alert method—in this case, barking—to signal to handlers when the scent is found.

Year two of the study will concentrate more on actual field work. Goals include:

•    Conducting a double-blind study (a verifiable scientific research method in which two groups, one a controlled results group and one an actual study group, are tested independently and results compared, but researchers aren’t told which group is the control);

•    Ongoing consultation with experts for verification of rigorous scientific methods, physics of odor dissemination and hunting, tracking and search-and-rescue training techniques (including continued communication with vine mealybug expert Professor Kent Daane of UC Berkeley to more fully understand the bug’s life cycle);

•    Determining the lowest threshold of scent that dogs can detect;

•    Studying whether dogs can detect vine mealybugs when the female’s pheromone isn’t present

(October through March);
•    Establishing the best field search pattern and scent detection logistics for large-scale searches; and

•    Preparing at least four dogs to be deployed in at-risk vineyards (beginning late spring 2007).

“It’s exciting work,” says Bergin. “The more we study how to use the skills of these animals, the more we can continue to help mankind in all kinds of ways. There doesn’t seem to be a limit to what dogs can do.”

Field work works

“We’ve supported the project—both in concept and financially—since its beginning,” says NVG’s Jennifer Kopp. “Our organization has donated funds, but we’ve also helped ADI solicit donations from our members. We’ve also provided sites for training the dogs.

“It’s at the point now of designing a practical implementation. We have to figure out how to get the dogs into the fields.”

As the dogs mature, more and more field work will naturally enter their training regimen. And as prime pheromone season rolls around in spring, vineyard owners will no doubt increase demand for inspections. Says Powers, “We have search forms now that we’re giving out to the vineyards, so if they suspect an infestation and want our help, they can call us out even though we’re still in research mode right now.” And as word of the program spreads, so will requests.

Any way the wind blows

Under a warm November sun, 50 or so curious onlookers gathered at the Napa Valley Viticultural Fair to watch a trio of retrievers named Rincon, Roz and Josh sniff out a hidden menace. Samples of synthesized vine mealybug pheromone had been randomly placed on grapevines outside of Cabernet Hall at the Napa Valley Exposition Fairgrounds. One at a time, the dogs inspected the plants; in each case, when a dog encountered the pheromone, it immediately sat at attention and barked.

So far, the ADI dogs are still working mainly with the synthesized pheromone, although field work has begun with randomly planted samples in local vineyards, “but the shift [to searching for actual infestations] will happen soon,” promises Powers.

“There have been some local infestations discovered by vineyard workers, and we’ve taken the dogs out to reinforce the associations we’ve been training them for—but we’re not quite ready yet.”
Ready or not, interest is growing.

“We’d like to get one of these dogs for our use; I’ve put my name in the hat,” says Eugene Rose of the Napa County Agricultural Commissioner’s office, who has a personal background raising and showing prize collies. “It’s an organic solution to what can be a big problem. We’ve tried training vineyard managers and winery staffs to inspect the vines, but it’s so hard for humans to pinpoint which vines are affected.”

Laura Breyer agrees. A California licensed pest control advisor (PCA) and owner of Sebastopol-based Breyer’s Vineyard IPM Service (IPM stands for “integrated pest management”), she’s been attending the Vine Mealybug Work Group’s meetings to keep abreast of new developments and thinks the dogs will be a huge help in early detection. “The vine mealybug is a relatively new pest,” she says, “but it has the potential to spread rapidly.

“Right now, the goal is to slow the spread. No one’s really looking to eradicate it at this point; thoughts now are about how to live with it and keep it controlled. But if you don’t know you have it…,” she trails off. She then admits her own interest in the project goes beyond that of a mere interested onlooker. “If they’re looking for dog handlers, I’m there.”

So far, indications are that dogs trained to sniff out vine mealybugs will be able to pinpoint an infestation’s exact location—down to a specific vine. The benefit to vineyard owners is clear. “Napa farmers are typically very environmentally aware and responsible,” says Jennifer Kopp. “And the chemicals we need to use to combat this pest just fly in the face of the sustainable farming practices we support. Earlier detection means treatment can be both isolated and more effective. This is the most innovative pest management solution I’ve ever heard of.”

Breyer confirms, “Vineyard owners are enthusiastic, but most are outwardly cautious. They’re all concerned about the vine mealybug and are at least familiar with the capabilities of search-and-rescue dogs. Owners with hunting dogs are by far the most excited, because the concept is more familiar to them.”

Given the overwhelmingly positive response to the mealybug sniffing dogs, ADI is already taking a long view of the project. “In the long run, we’re thinking of this as a separate business,” says Powers. “People will reserve a dog for a day or two to inspect the vines.”

Of course, some questions remain unanswered: How many acres can a dog cover in a day? How will environmental factors like wind current and wildlife affect a dog’s search success? And, perhaps most important, is determining whether the dogs can detect vine mealybugs distinctly from other pests (including other mealybug varieties) and when no pheromone is present.

“Female vine mealybugs release their pheromone in April and May. That time of year, there’s usually pretty heavy foliage on the vines, and it can make it hard for a handler to keep track of the dog, visually,” says Bergin. “Ideally, we’d like the dogs to find the bugs while they’re still burrowed under the bark, between January and March, when the vines are bare and it’s easier to keep visual contact.  

“I’m optimistic about their ability,” she continues cautiously, “but I always take a wait-and-see approach. I don’t want to get anyone’s hopes up.”

Then again, that’s why this is a research project. So far, all indications are positive…and expansive.

“Once this is proven successful, we can then branch out to explore other vineyard pests,” Powers agrees. “Of course, no dog would be trained in more than one insect, because the signals would get mixed up. But once the methodology is there, we can obviously expand the program to be more inclusive.

“Wine is a huge international economy,” she continues. “There’s no reason this type of program can’t be adapted to whatever regional pests there are. Plus, it’s going to be economical. It saves a lot of money for the vineyards, because rather than having to blanket all their vines or risk losing all their grapes, they’ll be able to target their resources. It’s also an organic solution which, with this area’s focus on sustainable agriculture, just fits right in. And everybody likes it—there’s no reason to be opposed to dogs running though vineyards. It’s a no-brainer.”