Climate driven changes to dispersal pathways in a climate change hotspot
Dr Paulina Cetina-Heredia1, Professor Moninya Roughan1, Dr Melinda Coleman2, Dr Andrew Jeffs3
1UNSW, Australia, Sydney, Australia, 2Department of Primary Industries, Fisheries NSW, Coffs Harbour, Australia, 3University of Auckland, Auckland, New Zealand
Larval dispersal by ocean currents influences species distributions and population dynamics; this study examines the impact of future climate on dispersal in a hotspot of climate change, southeastern Australia and across the Tasman Sea to New Zealand. We use outputs of an eddy-resolving configuration of the Ocean Forecast Australian Model that downscales an ensemble of 17 climate models forecasting RCP 8.5 from 2006-2101. Lagrangian trajectories of larvae with a variety of pelagic larval durations are modeled to contrast contemporary and future connectivity and settlement patterns. We find that climate-driven changes of larval pathways across the Tasman Sea modify settlement patterns around New Zealand; in contrast, export from mainland Australia to Tasmania is shown to increase potentially exacerbating range shifts such as those observed in the last decade. In addition, future settlement of local larvae in New Zealand is enhanced relative to that exported from Australia, which is diminished. Dispersal across the Tasman Sea is likely to diminish significantly with potential impacts to gene flow species resilience and fisheries management.
Biography:
Paulina has a BSc in Oceanography, a MSc degree in Physical Oceanography, and PhD from James Cook University. She is a postdoctoral fellow at UNSW interested in understanding how ocean physics influence the ecosystems’ health; to date her research has focused on (a) elucidating drivers and dynamics of ocean transport pathways and eddies (b) understanding how ocean circulation, larval life traits, and physiology shape the transport and survival of larvae, and (c) discerning the effect of climate-driven changes of the oceanic environment and circulation on biophysical dispersion.