Surveillance efforts are ramping up ahead of seeding in a bid to slow the spread of a new exotic pest capable of damaging crops and reducing yields across WA’s grain growing regions. The detection of Russian wheat aphids in two paddocks near Esperance in August sparked a biosecurity alert and swift response to control the spread of the pest. Department of Primary Industries and Regional Development teams were deployed to scour crops across the Esperance Port Zone in the week following the find, with ongoing monitoring critical to its management. DPIRD regional research agronomist Emma Pearse was on the ground focusing on wheat and barley crops from Salmon Gums to Scaddan. “We just essentially walked into the paddock and put our heads down and stared at the crop,” she said. “We tried to pick patches they’d be easier to find in — the corners, edges, tramlines — and targeted those, and once we spotted one you could see heaps.” “We initially spent a week and then after that it was every time you went out in the field you’d have a look just in case. You’d just keep an eye out.” The aphid has since been found in 20 locations across the Esperance Shire including Buraminya, Condingup, Coomalbidgup, Gibson, Howick Hill, Grass Patch, Salmon Gums and Truslove. While experts say “it is only a matter of time” before it is found right across the grainbelt, the pest — deemed manageable, but not eradicable — has only been found at levels below one per cent. And with the germination of barley grass — one of the aphids’ preferred hosts — just weeks away, DPIRD research scientist Svetlana Micic said a co-ordinated surveillance effort would be taking place across not only the Esperance Port Zone, but the Wheatbelt and Great Southern to curb its spread. “We’ll be looking for it in areas adjacent to the paddocks that had it last year and doing random surveillance throughout grain growing regions,” she said. “We fully expect it’s not going to be restricted to Esperance. It is predicted it will spread across our broadacre growing areas from Esperance to Geraldton.” The 2mm insect can cause discolouration and curling of leaves, stunted growth and bleached heads as early as seven days after infestation, leading to reduced yields. However, it does not have any trade implications as bulk grain is not a host for the aphid. The August find was the first time it had been detected in WA, but it has been reported in Victoria, New South Wales and Tasmania after it was first discovered in South Australia in 2016. It is known to travel long distances in the wind, as well as on plant hosts. The origins of those detected in WA are unknown. Landholders are urged to report the pests to DPIRD using its MyPestGuide Reporter or PestFax Reporter apps, or via the Pest and Disease Information Service on 9368 3080 and firstname.lastname@example.org.