Using verified photo observations from fishers and divers as an early indication of range shifts in the marine environment: the value of community engagement through citizen science

N.A. Moltschaniwskyj (1,2), N.Barrett (1), S. Frusher (1,4), D.C. Gledhill (4), A.J. Hobday (4), G. Jackson (5), J. Ramos (1), L.M. Robinson (1), J. Stuart-Smith (1), P. Walsh (1), G.T. Pecl (1,3)

1 Fisheries, Aquaculture & Coasts, Institute for Marine & Antarctic Studies, University of Tasmania, Private Bag 49, Hobart 7001, TAS, Australia

2 School of Environmental & Life Sciences, University of Newcastle, Ourimbah 2258, NSW, Australia

3 Centre for Marine Socioecology, Hobart, Tasmania

4 CSIRO Wealth from Oceans and Climate Adaptation Flagships, CSIRO Marine and Atmospheric Research, Hobart 7000, TAS, Australia

5 WA Fisheries and Marine Research Laboratories, PO Box 20, North Beach WA, 6920

Shifts in species` ranges are a frequently reported and globally ubiquitous impact of climate change, with rates of movement being particularly high in the sea. Early indication of which species are potentially extending their ranges can provide useful guidance for managers regarding investments in impact assessment, monitoring, or potential management intervention. Participants in citizen science projects have the capacity to record observations of their environment with precision and accuracy. Redmap (Range Extension Database and Mapping project,, invites Australians to submit photographs and data about unusual observations of marine species made while undertaking marine activities. A distributed data verification system uses ‘managed crowdsourcing` of scientists for data verification and processing of submitted observations. Therefore, Redmap can potentially generate significant amounts of previously unavailable data for researchers, while engaging the communities in climate science (using their own data). Using three years of data from Redmap and building on methods used in the early detection of invasive species, we developed a cost-effective and rapid screening assessment tool to classify levels of confidence in potential range extensions for a variety of marine species. Selected species identified as potentially range extending have then been the subject of focussed investigations, for example, genetic analyses and life history studies that have been able to confirm a recent rapid range extension and successful breeding in the ‘new’ range area. As such Redmap is an early indication system for changes occurring in the marine environment, and has the potential to play a pivotal role in informing management decisions and actions.