Bees as Biosecurity Biomonitors: exotic plant detection and identification to monitor plant invasions

Dr Andrew Cridge¹, Dr  Otto Hyink², Dr Karen Armstrong³, Dr Tom Harrop², Prof Peter Dearden²

¹Scion, Rotorua, New Zealand, ²University of Otago, Dunedin, New Zealand, ³Lincoln University, Lincoln, New Zealand

Biosecurity control and monitoring protect New Zealand from the invasion of harmful organisms. Recent plant incursions in New Zealand have highlighted that once new invaders have crossed into the country, they are tough to contain and require comprehensive resources to monitor and eradicate. Early identification of new invaders through extensive monitoring represents the best approach if eradication is to be successful. In this project, we use honeybees (Apis mellifera) to monitor the invasion and spread of noxious plant species. We use honeybees to collect pollen from monitoring sites across NZ and apply DNA sequencing to classify the pollen collected to detect and identify if they come from noxious plant species. This allows us to identify plant species that have evaded detection and established in the wild as well as determine the range of the incursion. Here we describe a study where we collected pollen from approximately 20 hives located across Dunedin, New Zealand, during the 2019/2020 season. Hives sites included residential, semi-rural, and town belt locations. Using internal pollen traps, pollen samples were collected from beehives over a two-day window at three weekly intervals across the season. Pollen samples were identified and quantified using DNA barcoding and microscopy. We evaluated this approach to identify pollen from noxious plants and determine the feasibility of using this approach for large-scale biosecurity monitoring.

Biography:

Dr Cridge’s research focuses on using eDNA as a tool for biosecurity monitoring of invasive weeds and insects, specifically tracking invasive plants by analysing pollen collected by bees in high-risk bio-security areas around New Zealand. Andrew is also utilising eDNA monitoring to investigate changes in land use on insect biodiversity, especially in translational and regenerative forestry systems. Andrew has additional interests and expertise in integrated pest management, insect genomics, pesticide resistance, and identification of novel insecticides. Currently, Dr Cridge is the Team Leader for Entomology at Scion.