Real-time detection of Red-eared Slider Turtles

Pond sliders (Trachemys scripta) are freshwater turtles that are naturally found across a wide  range in the United States and Central America. The Red-eared Slider (Trachemys scripta elegans) is one subspecies that occurs naturally in the lower Mississippi drainage system in the southern United States.

This species has been recognised as a serious threat when introduced to areas outside its natural range as it may cause serious loss of aquatic biodiversity. The World Conservation Union’s Invasive Species Specialist Group lists REST among the world’s 100 worst invasive species.

REST are the most widely kept pet animal in the world. At least 10 million are exported annually from the USA, to supply the demand for pets, specimens for reptile collectors, food and traditional medicines. REST exported from the USA were originally taken from wild populations. However, most of the animals now exported from the USA are raised on a small number of very large turtle ‘ranches’. Sliders can readily be purchased by mail order and over the internet, and are often shipped “bulk” as hatchlings. The Australian Quarantine and Inspection Service (AQIS) and Australian Customs Service report that travellers are regularly intercepted attempting to smuggle sliders into Australia. Sliders are also regularly intercepted in post and cargo arriving in Australia.

There are established incursions of REST in Australia, in particular Queensland and NSW, with Victoria and WA biosecurity officers removing several individuals when detected. One of the key challenges is the detection of these animals and also to have a method that can determine whether an eradication has been successful.

Through the Centre for Invasive Species Solutions, we have developed a species- specific assay for REST in Australia and have provided standards and guidelines for the use of REST eDNA detection tools to end-users as part of biosecurity surveillance operations.