eDNA sensing of Irukandji jellyfish

Ms Sarah (Sas) Stephenson¹, Dr Pascal Craw³, Professor Jamie Seymour², Olivia Rowley Rowley², Dr Robert Courtney², Dr Brano Kusy⁴

¹CSIRO Oceans and Atmosphere, Lucas Heights, Australia, ²James Cook University, Cairns, Australia, ³CSIRO Oceans and Atmosphere, Hobart, Australia, ⁴CSIRO Data61, Brisbane, Australia

Abstract:

With a changing coastal climate leading to changes to sea surface temperatures there is growing concern that the geographical range of Irukandji jellyfish (Carukia barnesi) may broaden. Detection of Irukandji jellyfish using traditional methods is extremely challenging and limited in its sensitivity to detection. Current records of Irukandji presence and absence rely on human sting records, reports from tourist operators and surf-life-savers net detection. To enhance the ecological knowledge on Irukandji jellyfish and develop a robust detection method, here, we propose an eDNA approach.

This study aims to develop a qPCR assay for rapid, accurate identification of Carukia barnesi DNA in environmental samples. We sequenced and analysed a range of target cubozoans (Carukia barnesi) and non-target cubozoan (Alatina, Chiropsella, Malo and Chironex) specimens through Sanger sequencing to identify potential qPCR primers. Specific and efficient qPCR primers from the mitochondrial CO1 target region were selected and validated. The eDNA qPCR assay results will be presented. Our Sanger sequencing results have been curated into an inhouse sequence database of Carukia barnesi sequences for investigating taxonomic matches and primer specificity.

Biography:

Sarah is a molecular ecologist in the vegetation and food webs team in Oceans and Atmosphere busines unit CSIRO. Sarah uses DNA-based techniques to describe ecosystem health. She is interested in scientific questions such as what is the eDNA decay rate for different species? What are the microbial communities associated with different coastal vegetation communities. Sarah’s current research focuses on developing qPCR assays for detection of target taxa such as Carukia barnesi (Irukandji jellyfish) and endangered species such as Glyphis glyphis (speartooth shark).