Scientific evidence suggests that the world’s oceans are warming at an accelerated rate due to anthropogenic activities. Waters off the south-east coast of Australia are warming almost four times the global average, caused in part by the strengthening of the East Australian Current. Ocean warming may impact the physiology, morphology, and behaviour of marine organisms that live close to their limits of thermal tolerance. To keep pace with their preferred thermal environments, over 100 marine species have been documented as shifting their geographic distribution polewards along the south-east coast of Australia at an average rate of 29 km/decade. The arrival of range-shifting species into new areas can be positive or negative, depending on species interactions. Impacts of concern include range-shifting sea urchins that can destroy kelp forests, stinging jellyfish and toxic microalgae that are detrimental to human health and have negative economic impacts on tourism, fisheries, and aquaculture.
It is important to develop predictive capacity to identify which species are likely to undertake such range-shifts. Recent studies suggest that populations with high connectivity and genetic diversity, fast growth rates, rapid population turnover, and high reproductive and predatory capacity are likely to better adapt to new environments, establish and prevail at extension zones, and out-compete local species.
Examination of life history characteristics, population dynamics, physiological limits, application of spatial modelling, and monitoring for changes in geographic distribution by citizen-science monitoring programs (e.g. REDMAP), may help scientists, managers and policy makers detect potential range shifting species and their impacts. This will enable us to mitigate threats and identify opportunities (e.g. new fishing target species).