Detection dogs in action

Specially trained detection dogs, Tahi and Nala, were put to work earlier this month in North Canterbury, sniffing out pest plant Chilean needle grass (CNG).

Plant scientist Dr Fiona Thomson, dog trainer and owner of Kuri Dog Centre Geoff Bowers, and dog handler Marina Paz, joined Environment Canterbury biosecurity staff at a newly identified site of CNG in Cheviot.

Environment Canterbury principal resource management advisor Laurence Smith said: "Tahi and Nala searched an area approximately 200m either side of a small infestation on Waiau West Road in Cheviot."

"This infestation had been controlled by biosecurity officers about two weeks prior, so the purpose of the dog’s search was to detect any plants that had been missed. Chilean needle grass plants are very difficult to detect once seed has dropped, so the dogs were put through the same area to see if they could find any plants not yet detected."

Nala searched the area first and didn’t detect any live plants, followed by Tahi who also didn’t detect any plants.

To reinforce the dogs’ search drive, at the end of the negative search a small bunch of CNG leaves were placed on the ground in the search area for the dogs to find.  Both Tahi and Nala found the leaves on their first pass of the site, and the leaves were then removed.

Dog trainer and owner of Kuri Dog Centre, Geoff Bowers said: “It’s important for the dogs to get this positive reinforcement at the end of their work to help maintain their search drive.  Too much negative searching and the dogs may lose interest.”

The potential for working more closely with Tahi, Nala, and other scent detection trained dogs in the future is huge.  "With their fantastic sense of smell, the dogs provide an opportunity to detect pest plants that aren’t that easy to find visually," said Smith.