title: Impacts and recovery from severe tropical cyclone Yasi on the Great Barrier Reef.
abstract: Full recovery of coral reefs from tropical cyclone (TC) damage can take decades, making cyclones a major driver of habitat condition where they occur regularly. Since 1985, 44 TCs generated gale force winds (≥17 metres/second) within the Great Barrier Reef Marine Park (GBRMP). Of the hurricane strength TCs (≥H1-Saffir Simpson scale; ≥ category 3 Australian scale), TC Yasi (February, 2011) was the largest. In the weeks after TC Yasi crossed the GBRMP, participating researchers, managers and rangers assessed the extent and severity of reef damage via 841 Reef Health and Impact Surveys at 70 reefs. Records were scaled into five damage levels representing increasingly widespread colony-level damage (1, 2, 3) and reef structural damage (4, 5). Average damage severity was significantly affected by direction (north vs south of the cyclone track), reef shelf position (mid-shelf vs outer-shelf) and habitat type. More outer-shelf reefs suffered structural damage than mid-shelf reefs within 150 km of the track. Structural damage spanned a greater latitudinal range for mid-shelf reefs than outer-shelf reefs (400 vs 300 km). Structural damage was patchily distributed at all distances, but more so as distance from the track increased. Damage extended much further from the track than during other recent intense cyclones that had smaller circulation sizes. Just over 15% (3,834 km2) of the total reef area of the GBRMP is estimated to have sustained some level of coral damage, with ~4% (949 km2) sustaining a degree of structural damage. TC Yasi likely caused the greatest loss of coral cover on the GBR in a 24-hour period since 1985. Severely impacted reefs have started to recover; coral cover increased an average of 4% between 2011 and 2013 at re-surveyed reefs. The in situ assessment of impacts described here is the largest in scale ever conducted on the Great Barrier Reef following a reef health disturbance.
authors: Great Barrier Reef Marine Park Authority, Townsville, QLD, 4810, Australia; Colleges of Business, Law and Governance and Marine and Environmental Sciences, James Cook University, Townsville, QLD, 4810, Australia.
authors: Roger
authors: R
authors: Beeden
authors: Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, 14853, United States of America; Laboratories d'Excellence <<CORAIL>> USR 3278 CNRS-EPHE, CRIOBE, Papetoai, Moorea, Polynésie Francaise.
authors: Jeffrey
authors: J
authors: Maynard
authors: School of Earth and Environmental Sciences, University of Wollongong, Wollongong, NSW, 2522, Australia; Australian Institute of Marine Science, Perth, WA, 6009, Australia.
authors: Marjetta
authors: M
authors: Puotinen
authors: Reef Ecologic, 10 Mt. Clifton Court, Alligator Creek, QLD, 4814, Australia.
authors: Paul
authors: P
authors: Marshall
authors: Great Barrier Reef Marine Park Authority, Townsville, QLD, 4810, Australia.
authors: Jen
authors: J
authors: Dryden
authors: Colleges of Business, Law and Governance and Marine and Environmental Sciences, James Cook University, Townsville, QLD, 4810, Australia; CSIRO Land and Water Flagship, Townsville, QLD, 4811, Australia.
authors: Jeremy
authors: J
authors: Goldberg
authors: Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, La Jolla, California, 92037, United States of America.
authors: Gareth
authors: G
authors: Williams
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000502:physiology*; D001315:Australia; D057894:Coral Reefs; D055867:Cyclonic Storms; D017753:Ecosystem