Using synthetic semiochemicals to train canines to detect bark beetle-infested trees

Abstract

In this proof of concept study, we report the off season training of two detection dogs on a series of synthetic semiochemicals associated with Ips typographus pest bark beetle infestations of spruce trees. Scent detection training allowed dogs to discriminate between physiologically-relevant infestation (target) odours, quantified by GC-MS using extracted ion chromatogram to be bio-active at levels of < 10-4 ng /15 min or lower, and natural non-target odours that might be encountered in the forest. Detection dogs trained to recognize four different synthetic pheromone compounds in the winter time, well before beetle flight, were able to detect natural infested spruce trees unknown to humans the following summer. The trained detection dogs were able to detect an infested spruce tree from the first hour of bark beetle attack until several weeks after the attack. Trained detection dogs appear to be more efficient than humans in detecting early bark beetle infestations because the canines ability to cover a greater area and by olfaction detect infestations from a far greater distance than can humans. Infested spruce trees could be detected by trained detection dogs out to more than 100 m.\n\nKey MessageO_LIDetection dogs were rapidly trained to locate release of synthetic bark beetle pheromone components\nC_LIO_LISynthetics allowed dog training off-season both in laboratory and field\nC_LIO_LIDogs trained on synthetics detected naturally target pest insect attacked trees at a distance of more than 100 m.\nC_LIO_LIThe method allows rapid removal of single, first attacked trees before offspring emergence, thus curbing local pest increase and lowering spread of attacks in the landscap\nC_LI