Libby Liggins1, David Aguirre1, Irene Middleton2
1University of Auckland, New Zealand - 2National Institute of Water and Atmospheric research, New Zealand
Identifying the species undergoing range shifts and predicting where and when future climate-mediated range shifts will occur is critical to proactively managing marine biodiversity. However, identifying species range shifts is often hampered by a lack of baseline distribution data and informed surveillance. Marine fishes are valuable indicators of current and future change; they are early responders to ocean warming, and they are charismatic and highly visible, increasing the ease of monitoring. Our research programme has combined data derived from scientific surveys, commercial catches, and local ecological knowledge of experts and non-experts to determine the spatio-temporal ranges of tropical, subtropical, and rare fishes in Aotearoa New Zealand and to describe their range dynamics over recent decades. Observations of marine fishes were scored using a qualitative decision-tree approach to classify occurrences as within range, potential range extensions, or human-mediated dispersal events. Our research indicates that the occurrences and diversity of tropical, subtropical, and rare fishes in Aotearoa New Zealand has increased over the past 50 years. We found 57 species of marine fishes occurring out-of-range and a total of 41 occurrences that constituted a potential range shift. Locations with a high occurrence of potentially range shifting fishes were centred in north-eastern Aotearoa New Zealand, with occurrences of potentially range shifting fishes decreasing with increasing latitude. The ease of our approach and the intuitive outputs should appeal to managers and science practitioners concerned with climate-induced biodiversity changes and alien species detection. We present a list of range shifting marine fishes by management region to facilitate their monitoring and impact mitigation.
Biography
Libby is an Associate Professor in Marine Molecular Ecology at Waipapa Taumata Rau (the University of Auckland). She studies the generation and changing nature of biodiversity in the Southwest Pacific, often using genomics in combination with ecological data and modelling approaches. Libby collaborates in several international research consortia and scientific committees advocating for open data, knowledge transfer, and appropriate data stewardship.