Dogs are known to be excellent sniffers, often lending their skills to first responders. They may also be useful in providing early detection and rapid response in the face of spotted lanternflies, new published research shows.

Spotted lanternfly, an invasive species that causes significant damage to grape vines, fruit trees, and hardwoods, was discovered in North America in 2014 in Pennsylvania. Neighboring states, like New York, began investing heavily in preventing the pest from establishing in their forests and vineyards.

“Obviously, catching a species when populations are small is ideal, but if you can’t find them because the population is so small, it makes that effort difficult,” said Carrie Brown-Lima, regional administrator of the Northeast Climate Adaption Science Center of the U.S. Geological Survey. “While spotted lanternfly adults are flashy and easy to see, the egg masses that they deposit are camouflaged and they’re not easy to find. Imagine you’re out in the woods trying to find egg masses just by visual searching; you have a pretty high chance of missing them.”

Conservation dogs have been trained to detect various invasive species across the country. Dogs are used to control the spread of zebra mussels out West, Scotch broom in New York, yellow star thistle in Colorado, Chinese bush clover in Iowa, and many other invasive plants, animals and insects. Dogs can also help find and protect endangered species.

Because dog teams are both a time and financial investment, research is needed to ensure they are more effective at detecting invasive species than other methods, like using human surveyors. As part of Brown-Lima’s study, a Labrador retriever and a Belgian Malinois were trained to detect the scent of spotted lanternfly egg masses. Live egg masses were collected to be used as training samples, ranging from whole, covered egg masses attached to substrate to partially covered or uncovered egg masses. Humans were also trained to detect egg masses and distinguish them from other insect egg masses. Twenty survey sites were assessed from December 2020 to May 2021.

“This study took place in vineyards and forests, and what we found is that when you’re in a forest habitat where egg masses are sparser and more difficult to see, that’s when the dogs outperform the humans,” Brown-Lima said.

The two dogs trained in the study had 3.4 times more detections than humans in forests. Overall, in forests, dogs found 7.6 egg masses per hour versus 6.7 per hour for humans, although dogs spent more time searching than humans. However, in vineyards, humans outperformed dogs, detecting 1.8 times more egg masses than dogs. Brown-Lima explained that during the study, there were more egg masses than anticipated in the vineyards and that they were visually easy to find for human surveyors. Dogs are best suited and perform better in environments where the scent isn’t everywhere, and the target species is found in low densities.

“When you’re in a scenario where you’re trying to remove camouflaged masses or identify if (an invasive species) population is spreading, a dog can be very valuable. Their noses are much better than our eyes,” Brown-Lima noted.

However, environmental context matters in the decision to deploy conservation dogs. For example, the population of spotted lanternflies in the Midwest has exploded, leaving many states battling swarms of the insects. If spotted lanternflies are already widespread, using conservation dogs to pinpoint individual insects or egg masses is less impactful because the invasion is already beyond a manageable threshold. Instead, broad-scale management and control measures are more effective. Dogs specifically trained in detecting spotted lanternflies would be best employed in areas without established populations to prevent the continued spread of the insect.

Although using dogs in conservation work can be expensive, Brown-Lima said that human surveyors can be costly, too. The difference is that dogs can be more effective and potentially a resource-saving approach. Still, there aren’t many dog teams available to complete conservation work, and Brown-Lima hopes that studies like hers can highlight how effective dogs are as a tool and incentivize organizations to use dogs for this purpose.

“Dogs are such great ambassadors for making people aware of the spread of invasives,” she said. “Who doesn’t love a dog?”