Decadal changes in turbid-water coral communities at Pandora Reef, Great Barrier Reef

Brief description

The extent to which short-term 'losers' (vulnerable to episodic disturbances) can continue to re-establish themselves was examined at Pandora Reef, an inshore shallow turbid-water patch reef. Coral community changes were followed in sites chosen to maximise the range of depth, shelter and species composition represented at Pandora Reef.Data was collected in 1981, 1985, 1991, 1997, 2001 and 2005 from 7 long-term monitoring sites, 4 photo quadrats and 3 sets of video transects (from 1991), which were established on the reef. Photo transects (9 cells in each transect grid) were set up on both the fore- (P1, P2) and back-reefs (P3, P4). In each cell the number of each species was recorded and then assigned to its broader taxonomic group (hard coral, algae, and soft coral) as a total. Benthic cover of each taxonomic group was assessed in 10% increments, and any difference (plus or minus) calculated.Video survey transects (250 m long, made up of five 50 m sub-transects) were carried out on sections of the reef reflecting exposure scales: most sheltered (V1), intermediate shelter (V2), and most wave-exposed (V3). In the laboratory, 5 fixed points were sampled at 40 paused positions separated by a fixed time interval, giving a total of 200 points per sub-transect. In V3 where the transect wraps around the reef's northeast corner, the fifth sub-transect (t5) is characterised separately from the rest (t1-4).Pulse disturbances potentially affecting Pandora Reef were: cyclones (Gertie, 1971; Althea, 1971; Dawn 1977; Keith, 1979; Sadie 1994; Justin, 1997; Tessie, 2000); floods (Burdekin River, 1974, 1991); and heated periods (1973, 1987, 1998, 2002). To determine the variation of impacts from pulse disturbances (and recovery from these) around the reef, depending on the degree of exposure to the events, the relative local abundance of tolerant or susceptible species, and site-specific variability in the processes and rates of recovery of impacted coral populations. Species recorded in the quadrats:Corals: Acropora cerialis; Acropora cuneata; Acropora elseyi; Acropora formosa; Acropora hyacinthus; Alveopora sp.; Echinopora lamellosa; Favid species; Fungia sp.; Galaxea astreata; Galaxea fascicularis.; Goniastrea sp.; Goniopora sp.; Millepora tenella; Montipora aequituberculata; Montipora spp.; Pectinia lactuca; Pectinia lactuca; Platygyra lamellina; Pocillopora damicornis; Pocillopora sp.; Porites cylindrica; Porites massive; Psammocora contigua; Psammocora digitata; Stylophora hystrix; Stylophora pistillata; Turbinaria frondens; Turbinaria mesenterina; Turbinaria patula; other hard coral. Acropora growth forms (bush, staghorn, plate) and rubble were recorded.Soft corals: Briarium sp.; Cladiella sp.; Clavularia sp.; Lobophytum sp.; Sarcophyton sp.; Sinularia sp.; Xenia sp.; Zoanthus sp.Algae: Asparagopsis sp.; Dictyota sp.; fleshy macroalgae; Laurencia sp.; Lobophora sp.; Padina sp.; Sargassum sp.; Sponges:- 'Porifera'; Brown sponge

Lineage

Maintenance and Update Frequency: notPlanned

Notes

Credit
Done, Terence J (Terry), Dr (Principal Investigator)