Miss Therese Miller1,2, Julia Barth3, Chrysa Gubili4, Hannah Hampton2, Andrew Jeffs1, Robert Jehle5, Michael Matschiner6, Ezgi Ogutcen7, Amandine Sabadel8,9, Robert Schabetsberger7, Xavier Pochon1,2
1Institute of Marine Science, University Of Auckland, Auckland, New Zealand, 2Cawthron Institute, Nelson, New Zealand, 3Department of Environmental Sciences, Zoological Institute, University of Basel, , Switzerland, 4Fisheries Institute, Kavala, Greece, 5School of Science, Engineering and Environment, University of Salford, Salford, United Kingdom, 6Natural History Museum, University of Oslo, Oslo, Norway, 7Department of Environment and Biodiversity, Paris Lodron University of Salzburg, Salzburg, Austria, 8Department of Environmental Science, Auckland University of Technology, Auckland, New Zealand, 9National Institute of Water and Air, Wellington, New Zealand
Biography:
Therese Miller is a PhD student at the University of Auckland based at the Cawthron Institute in Nelson. Prior to coming to New Zealand, she completed a Bachelor of Science degree at the University of Florida and a Master of Science degree at the University of Guam. She studied marine invertebrate biodiversity and microbial ecology during her undergraduate and master's studies, and now is using environmental DNA to detect the presence of New Zealand eels and characterise their environment.
Abstract:
Diadromous eels are a culturally and ecologically significant species in Aotearoa – New Zealand, particularly to indigenous Māori, and an indicator species of environmental health. Spawning sites and larval dispersal routes of longfin (Anguilla dieffenbachii) and shortfin (A. australis schmidtii) eels from Aotearoa – New Zealand are unknown. Migratory tracks of marine species are commonly researched using satellite tracking, but that approach has been unsuccessful with detecting spawning sites of migratory eels. Currently, environmental DNA (eDNA) is an effective tool for detecting rare and cryptic species and has been used to detect Japanese eels spawning near the Marianas Islands. This project aims to develop new species-specific primers to detect longfin and shortfin eels as they migrate from New Zealand's fresh waters to their spawning sites in the western south Pacific (WSP) Ocean.
Species-specific droplet digital PCR (ddPCR) primers and probes were designed for the longfin and shortfin eels using a unique library of 344 whole mitochondrial genomes representing all species of Anguilla eels known to date. Four sets of TaqMan probe ddPCR assays were designed in the D-loop region and validated in silico and in vitro using DNA from tissues of trans-Pacific eels with no cross-reactivity detected. A series of ten-fold dilutions were used to assess limits of detection and quantification. These assays will be used to investigate the feasibility of using onboard eDNA analysis to unravel the migration pathways of New Zealand’s eels in the ‘Great Migration Research Cruise’ through the WSP in October and November 2024.