title: Historical photographs revisited: A case study for dating and characterizing recent loss of coral cover on the inshore Great Barrier Reef.
abstract: Long-term data with high-precision chronology are essential to elucidate past ecological changes on coral reefs beyond the period of modern-day monitoring programs. In 2012 we revisited two inshore reefs within the central Great Barrier Reef, where a series of historical photographs document a loss of hard coral cover between c.1890-1994 AD. Here we use an integrated approach that includes high-precision U-Th dating specifically tailored for determining the age of extremely young corals to provide a robust, objective characterisation of ecological transition. The timing of mortality for most of the dead in situ corals sampled from the historical photograph locations was found to coincide with major flood events in 1990-1991 at Bramston Reef and 1970 and 2008 at Stone Island. Evidence of some recovery was found at Bramston Reef with living coral genera similar to what was described in c.1890 present in 2012. In contrast, very little sign of coral re-establishment was found at Stone Island suggesting delayed recovery. These results provide a valuable reference point for managers to continue monitoring the recovery (or lack thereof) of coral communities at these reefs.
authors.affiliation: School of Earth Sciences, The University of Queensland, Brisbane QLD 4072 Australia.
authors.forename: Tara R
authors.initials: TR
authors.lastname: Clark
authors.affiliation: School of Earth Sciences, The University of Queensland, Brisbane QLD 4072 Australia.
authors.forename: Nicole D
authors.initials: ND
authors.lastname: Leonard
authors.affiliation: School of Earth Sciences, The University of Queensland, Brisbane QLD 4072 Australia.
authors.forename: Jian-Xin
authors.initials: JX
authors.lastname: Zhao
authors.affiliation: Centre for Tropical Water and Aquatic Ecosystem Research, James Cook University, Townsville, QLD 4811 Australia.
authors.forename: Jon
authors.initials: J
authors.lastname: Brodie
authors.affiliation: ARC Centre of Excellence in Coral Reef Studies, James Cook University, Townsville, QLD 4811 Australia.
authors.forename: Laurence J
authors.initials: LJ
authors.lastname: McCook
authors.affiliation: Great Barrier Reef Marine Park Authority, 2-68 Flinders Street, PO Box 1379, Townsville, QLD 4810 Australia.
authors.forename: David R
authors.initials: DR
authors.lastname: Wachenfeld
authors.affiliation: School of Earth Sciences, The University of Queensland, Brisbane QLD 4072 Australia.
authors.forename: Ai
authors.initials: A
authors.lastname: Duc Nguyen
authors.affiliation: ARC Centre of Excellence in Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane QLD 4072 Australia.
authors.forename: Hannah L
authors.initials: HL
authors.lastname: Markham
authors.affiliation: ARC Centre of Excellence in Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane QLD 4072 Australia.
authors.forename: John M
authors.initials: JM
authors.lastname: Pandolfi
mesh_terms: D000818:Animals; D037421:Anthozoa; D001315:Australia; D057894:Coral Reefs; D017753:Ecosystem; D004784:Environmental Monitoring / Q000266:history; D049672:History, 19th Century; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans
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