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The north-east Australian margin is the largest modern example of a tropical mixed siliciclastic/carbonate depositional system, with an outer shelf hosting the Great Barrier Reef (GBR) and an inner shelf dominated by fluvially sourced siliciclastic sediment wedges. The long-term interplay between these sediment components and sea level is recorded in the Queensland Trough, a 1–2 km deep N–S elongate basin situated between the GBR platform and the Queensland Plateau. In this paper, 154 samples from 45 surface grabs and six well-dated piston cores were analysed for total carbonate content, carbonate mineralogy and Sr concentration to establish spatial and temporal patterns of carbonate accumulation in the Queensland Trough over the last 300 kyr. Surface carbonate contents are lowest on the inner-shelf (<5%) and in the trough axis (<60%) because of siliciclastic dilution. Carbonate on the shelf is mostly Sr-rich aragonite and high-Mg calcite (HMC), whereas that in the basin is mostly low-Mg calcite. Once normalized to remove the effects of siliciclastic dilution, surface Sr-rich aragonite and HMC abundances decrease linearly to background levels ≈ 100 km seaward of the shelf edge. Core samples show that, over time, normalized aragonite and Sr abundances are greatest during periods of shelf flooding and lowest when sea level drops below the shelf edge. This is consistent with changes in the production of coral and calcareous algae, and the shedding of their debris from the shelf. Interestingly, normalized HMC concentrations on the slope peak during periods of major transgression, perhaps because of maximum off-shelf transport from inter-reef areas or intermediate water dissolution. After accounting for siliciclastic dilution, there are strong similarities in both spatial and temporal patterns of carbonate minerals between slopes and basins of the north-east Australian margin and those of pure carbonate margins such as the Bahamas. A limited set of basic processes, including the formation and breakdown of carbonate on the shelf, the transport of carbonate off the shelf and eustatic sea level, probably controls carbonate accumulation in slope and basin settings of tropical environments, irrespective of proximal siliciclastic sediment sources. [ABSTRACT FROM AUTHOR]

This paper investigates the use of aesthetic value as a criterion by which the significance of heritage places is assessed. It is argued that current heritage management practice has not engaged with the extensive discourse relating to aesthetics, and therefore confines aesthetics to a particular class and culture, and an inert view of only one of our sensory experiences. Historical records relating to the Great Barrier Reef are used to show how aesthetic appreciation of the area has changed over time.The data suggest that the failure to recognise an aesthetic that is primarily non-visual can lead to changes in landscape and loss of associated value. It also suggests that aesthetic values change rapidly and are influenced by social and technological factors. [ABSTRACT FROM AUTHOR]

Abstract: The use of landholder typologies to assist in the development of natural resource management (NRM) policies and agricultural extension programs has increased considerably in the past decade. In this paper we explore the potential of developing a typology of graziers to more effectively tailor policies and programs with the aim of improving land management outcomes. This is of particular importance since growing public concern about the environmental performance of the beef industry has led to increasing pressures on graziers to change their land management practices to decrease off-property impacts. To gain a better understanding of graziers’ land management practices and the factors that inform their decisions on how they manage their land we first developed a conceptual model of the relationship between grazier and grazing land where both can, ideally, thrive through conscious and timely land management decisions made and implemented by the grazier. A successful grazier land relationship is likely to be consistent with value systems and social and economic factors, although the particulars of any individual approach may vary spatially and temporally. These factors, in particular graziers’ values and motivations to follow a particular management strategy, guided the development of our typology of graziers. Australia''s Bowen-Broken basin, which has been identified as a major contributor of sediment and nutrients that enter the Great Barrier Reef lagoon, served as a case study for this research. Three broad types of graziers emerged: (1) traditionalists, (2) diversifiers, and (3) innovators. The authors argue that by understanding graziers’ values and motivations underlying each of the grazier types, government agencies and NRM organisations can more effectively tailor their policy and extension programs towards specific types of graziers and can work with specific groups to achieve reductions in sediment and nutrient runoff from grazing properties. [Copyright &y& Elsevier]

The Pied Imperial-Pigeon (Ducula bicolor) is a summer migrant to northern Australia, and nests colonially on many islands of the Great Barrier Reef, Queensland. Numbers are perceived to have declined as a result of large-scale shooting in the past and clearing of their mainland feeding grounds. To obtain evidence of any population changes, 1–10 counts were made each breeding season of the evening flight from the mainland to a nesting colony on North Brook Island. The counts began in 1965 and have continued for 50 years. The count represents one individual of a pair that visits the mainland to feed and returns in the evening. In the 1965–66 breeding season, the December count (the count used to compare years) was 4692 birds. Over the following three seasons, numbers declined to a low of 1451 birds in 1968–69; this decline was attributed to shooting of up to 1100 birds at a time. Large-scale shooting stopped in 1968 and was followed by a steady exponential increase (y = 3370.4e0.0908x in numbers over 23 years to 29 818 birds in the 1992–93 season. Numbers have fluctuated between ∼25 000 and 35 000 individuals over the following 18 years. A tropical cyclone of extreme intensity affected the pigeons' breeding site on North Brook Island and their mainland feeding areas in February 2011. In the following breeding season of 2011–12, numbers fell to 5311, but recovered to 21 088 in the 2012–13 season. The dramatic drop in numbers was attributed to the pigeons moving elsewhere for the 2011–12 season. It is predicted that the post-cyclonic number of 21 088 will take 4 years to recover to 30 000. The counts are a simple and somewhat coarse measure of population trends, but provide a population baseline for more sophisticated studies on the movements of pigeons and their responses to long-term changes in habitat and climate. [ABSTRACT FROM AUTHOR]

A new species of Numbakulla Guţu & Heard, 2002 (Tanaidacea) is described from Heron Island (southern Great Barrier Reef, Queensland) collected during the Census of Coral Reefs Ecosystem (CReefs) program. The new species is the third member of the family and can be recognized by the combination of characters as: length/width ratio of the body, which is 6:7, pereonite 4 longer than the rest, the presence of eyes, a blunt rostrum, antenna article 2 elongated, cheliped carpus with row of inner setae, pereopod 6 carpus with spines, pleopod endopod with denticles. [ABSTRACT FROM AUTHOR]

The challenge of developing environmental outcomes acceptable to stakeholders with different values is well documented. Discourse analysis provides insights into how the views of different stakeholders affect decision making. We studied the discourses of key actors associated with the implementation of a Turtle and Dugong Hunting Management Plan developed by Hope Vale Aboriginal community in the Great Barrier Reef World Heritage Area, Australia. The discourses of the environmental managers and community members were very different. Hope Vale people prioritized cultural well-being; the staff of management agencies prioritized biodiversity outcomes. These differences precluded effective outcomes despite considerable investment in hunting management over more than 20 years by both groups. Understanding the discursive terrain within environmental management domains can inform environmental decision making and the implementation of agreed management arrangements, enabling biodiversity objectives and Indigenous cultural aspirations to be met in a socially just, economically viable, and environmentally sustainable way. [ABSTRACT FROM AUTHOR]

The historical exploitation of marine resources in Queensland has only been partially documented. In particular, the history of the commercial fishing of dugongs and marine turtles has received comparatively little scholarly attention. Since European settlement in Queensland, various human activities have exploited these resources. We present documentary and oral history evidence of the scale of those industries. Based on extensive archival and oral history research, we argue that diverse fishing practices occurred and that the sustained exploitation of dugongs, green turtles, and hawksbill turtles led to observable declines in the numbers of these animals – now species of conservation concern. [ABSTRACT FROM AUTHOR]

A sedimentological and stratigraphic study of Low Isles Reef off northern Queensland, Australia was carried out to improve understanding of factors that have governed Late Holocene carbonate deposition and reef development on the inner to middle shelf of the northern Great Barrier Reef. Low Isles Reef is one of 46 low wooded island-reefs unique to the northern Great Barrier Reef, which are situated in areas that lie in reach of river flood plumes and where inter-reef sediments are dominated by terrigenous mud. Radiocarbon ages from surface and subsurface sediment samples indicate that Low Isles Reef began to form at ca 3000 y BP, several thousand years after the Holocene sea-level stillstand, and reached sea-level soon after (within ∼500 years). Maximum reef productivity, marked by the development of mature reef flats that contributed sediment to a central lagoon, was restricted to a narrow window of time, between 3000 and 2000 y BP. This interval corresponds to: (i) a fall in relative sea-level, from ∼1 m above present at ca 5500 y BP to the current datum between 3000 and 2000 y BP; and (ii) a regional climate transition from pluvial (wetter) to the more arid conditions of today. The most recent stage of development (ca 2000-0 y BP) is characterised by extremely low rates of carbonate production and a dominance of destructive reef processes, namely storm-driven remobilisation of reef-top sediments and transport of broken coral debris from the reef front and margins to the reef top. Results of the present study enhance existing models of reef development for the Great Barrier Reef that are based on regional variations in reef-surface morphology and highlight the role of climate in controlling the timing and regional distribution of carbonate production in this classic mixed carbonate-siliciclastic environment. [ABSTRACT FROM AUTHOR]

Eight, multicentury, Porites coral cores were used to develop a 373-year chronology by cross-dating techniques adapted from dendrochronology. Characteristic patterns of distinct luminescent lines within the coral skeletons were matched between coral cores from inshore and mid-shelf reefs in the central Great Barrier Reef, Australia. Skeleton-plots of luminescent banding were produced for each core and combined into a master chronology back to AD 1615. In addition to improving dating control, the luminescence master chronology provides a proxy for Burdekin River runoff and Queensland summer rainfall. Variations in the magnitude of the correlation between the luminescence master and the Mann et al. (2000) NINO3 sea-surface temperature reconstruction provides insights into the long-term stability of El Niño-Southern Oscillation (ENSO) teleconnections. Burdekin River runoff was significantly inversely related to ENSO variability for much of the period from the AD 1650s to 1800, suggesting that ENSO-related teleconnections were as dominant then as in recent decades. The extremely dry mid-1760s to mid-1780s stand out as a period of anomalously positive correlation between river runoff and the NINO3 reconstruction. Weak ENSO teleconnections are apparent from the 1800s to 1870s, when conditions were possibly similar to those reported for the 1920s-1950s. [ABSTRACT FROM AUTHOR]

Massive, long-lived corals in inshore waters of the Great Barrier Reef contain yellow-green fluorescent bands. These bands are due to terrestrial humic and fulvic compounds incorporated into the coral skeleton during high river flow events. Fluorescence measurements are presented for two colonies of Porites spp. from locations in the path of the Burdekin River floodwaters - the major river in north Queensland draining into the Coral Sea. The records extend from AD 1737 to 1980 and 1644 to 1986, respectively. The two independent coral records show a high degree of similarity. The two series are combined and used to reconstruct Burdekin River runoff for the period AD 1655 to 1980. The regression model accounts for 83% of the annual (water year) variability of Burdekin River flow and is verified over independent data. The 337-year reconstruction thus increases by threefold the length of record for considering interannual to decadal climate variations in northeast Australia. Instrumental and reconstructed Burdekin River runoff are closely related to an index of summer monsoon rainfall in Queensland. Thus, the reconstruction provides insights into the behaviour over the past three centuries of both a major tropical river system and the highly variable summer monsoon rainfall in northeast Australia. The reconstructed series shows wetter conditions (higher runoff) in the lae-seventeenth to mid-eighteenth centuries and in the late-nineteenth century. Drier conditions (lower runoff) are reconstructed in the late-eighteenth to mid-nineteenth centuries and in the mid-twentieth century. [ABSTRACT FROM AUTHOR]