Seek and you shall find - early detection success stories

Abstract

Preventing the establishment of high-risk invasive plants generates an estimated benefit to cost ratio of 100:1. In Queensland, the species that pose the highest risk and that are not present in the state, or are the subject of prevention or eradication actions, are listed as prohibited matter under the Biosecurity Act 2014.

Pre-emptive surveillance is our best chance of detecting incursions of these high-risk target species while populations are small and vulnerable to complete elimination. However, early detection is challenging and needs to be approached strategically.

Biosecurity Queensland and partners have developed several surveillance strategies, including (1) the Weed Spotters Network, a network of 1800 citizen scientists trained to detect and report target species, (2) monitoring observations of target species submitted through the online biodiversity cataloguing application iNaturalist, and (3) monitoring ‘sentinel sites’ – locations where target species are most likely to be found.

Three outstanding early detection success stories are: (1) yellow fever tree (Vachellia xanthophloea) reported through the Weed Spotters Network; (2) Siam weed (Chromolaena odorata) detected via iNaturalist and the Atlas of Living Australia Biosecurity Alerts Service; and (3) tropical soda apple (Solanum viarum) detected at a sentinel site. In all three examples, detection resulted in delimitation and removal of the population. Such action is predicted to have prevented multimillion-dollar problems from developing. Tropical soda apple alone costs Florida cattle producers an estimated US$15 million per annum in lost production.

These case studies demonstrate that implementing multiple targeted surveillance strategies and engaging citizen scientists increases the likelihood of early detection.