Articles

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Of the five World Heritage sites in Queensland, two are located in Tropical North Queensland and provide the region with its key iconic experiences. However, not all tourists visit these sites. This paper seeks to identify the reasons why a significant number of tourists do not visit these sites. Based on a survey of departing domestic and international visitors at Cairns domestic airport throughout 2007, this study identifies the visitor segment who do not visit the region’s major natural attractions.

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This research incorporated field and experimental work on benthic foraminifera as indicators for water quality in the Great Barrier Reef (GBR). Firstly, distribution of benthic foraminifera was examined on 20 reefs in four regions of the GBR (Princess Charlotte Bay, Wet Tropics, Whitsunday Area, and Mid/Outer-shelf reefs), and along a water quality (WQ) gradient in the Whitsunday region. Secondly, manipulative laboratory experiments were carried out to determine whether the distribution of symbiont-bearing foraminifera is controlled by light levels or other environmental factors.

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Tropical storms (cyclones, hurricanes or typhoons) are the most severe form of mechanical disturbance of coral reefs. In 2005, the severe Tropical Cyclone Ingrid crossed the Far Northern Great Barrier Reef. This storm provided a unique opportunity to improve understanding of the extent and type of damage inflicted on inshore and offshore coral reefs along a gradient of wind speeds. Surveys of 82 sites on 32 reefs along the wind gradient showed that the types and intensity of disturbance were well explained by local maximum wind speed, and by spatial and biotic factors. While offshore reefs had the deepest depth of damage, inshore reefs had the greatest rates of coral breakage and dislodgement. On a severely affected inshore reef, hard coral cover decreased about 8-fold, taxonomic richness decreased 2.5-fold, the density of coral recruits decreased by 30%, while massive coral cover remained unaltered. Maximum winds <28 cm s-1 for <12 hours inflicted only minor damage on any reef, but winds >33 m s-1 and >40 m s-1 caused catastrophic damage on inshore and offshore reefs, respectively. Observations from this cyclone were used to predict potential changes in storm-related coral loss at a scenario of altered cyclone intensity.

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Reef-building corals are under increasing physiological stress from a changing climate and ocean absorption of increasing atmospheric CO2. We investigated 328 colonies of massive Porites corals from 69 reefs of the Great Barrier Reef (GBR). Their skeletal records show that throughout the GBR, calcification has declined by 14.2% since 1990, predominantly due to extension declining by 13.3%. The data suggest such a severe and sudden decline in calcification is unprecedented in at least the last 400 years. Calcification increases linearly with increasing large-scale sea surface temperature, but responds non-linearly to annual temperature anomalies. The causes for the decline remain unknown, however this study suggests that increasing temperature stress and declining seawater aragonite saturation state may be diminishing the ability of GBR corals to deposit calcium carbonate.

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Most marine invasive species have been introduced to Australian waters unintentionally through shipping activities and mariculture.

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Dugongs (Dugong dugon) are marine mammals, which are commonly known as sea cows. Australia is home to most of the world’s dugongs. They live in northern waters between Shark Bay in Western Australia and Moreton Bay in Queensland. One of the reasons for nominating the Great Barrier Reef as a World Heritage Area in 1981 was its importance as a feeding ground for large populations of dugongs.

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Tropical northern Australian waters are home to a number of harmful jellyfish, including the large multi-tentacled deadly box jellyfish Chironex fleckeri and several species of smaller jellyfish known to cause the debilitating Irukandji syndrome.

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Coral reef fish are caught by hook and line along the length of the Great Barrier Reef from the Torres Strait south to Fraser Island. More than 120 fish species are caught in the commercial line fishery, although only a few of them are actively targeted by commercial fishers. The high-value target species include coral trout, red throat emperor, red emperor, tropical snapper and Spanish mackerel.

Recreational anglers also target these species, particularly highly prized trophy species such as Spanish mackerel, red emperor and coral trout.

Research on the biology of fish species and the impacts of fishing is helping managers balance the needs of users while maintaining reef fish stocks and the reef ecosystem for future generations.

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Identifying the principal spatial patterns in biodiversity of corals is a requirement for effective ecosystem management. This article summarises large-scale patterns in hard coral biodiversity on the GBR.

The study is based on one-off surveys of 599 sites on 118 inshore reefs and 17 mid-and outer-shelf reefs along 1300 km of Australia’s Great Barrier Reef (GBR) (Fig. 1), conducted between 1994 and 2001. More details are found in Devantier et al. (2006).

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Water quality (WQ) is an important determinant of ecosystem health in the Great Barrier Reef (GBR). This articles summarise some of the main spatial patterns and seasonal changes in water quality. The information is based on two Reports, Death (2007), and De’ath and Fabricius (2008).

The main findings are:

(1) Space-time models are poor predictors of WQ parameters. Between 0% and 40% of the variation in WQ parameters is typically predictable, with chlorophyll and suspended solids being well predicted and dissolved forms of nitrogen being very poorly predicted.

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Soft corals, sea fans and gorgonians are common names for a group with the scientific name Octocorallia or Alcyonacea. About 100 genera in 23 families are known to occur in shallow Indo-Pacific coral reefs. Octocorals are ecologically important components of the coral reef landscape, and being beautiful and colourful, are an attraction for divers.

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The study reported here defines water quality guideline values for the Great Barrier Reef (GBR). The analyses showed that algal cover and the richness of hard corals and octocorals were strongly related to chlorophyll and water clarity. The richness of both hard corals and phototrophic octocorals decreased with increasing turbidity and chlorophyll. Heterotrophic octocorals increased with greater turbidity and slightly decreased with higher chlorophyll. Guideline values of maximum mean annual concentrations of chlorophyll of 0.45 g/L and minimum mean annual Secchi depth of 10 m are proposed for both coastal and inshore zones in all regions (at shallower depths the sea floor will be visible).

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Biology is the study of all living organisms (plants, animals, microorganisms) and how they interact with each other and their environment. It examines the structure, classification, function, growth, origin, evolution, and distribution of all living things.

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Zooxanthellae are unicellular, golden-brown algae (dinoflagellates) that live either in the water column as plankton or symbiotically inside the tissue of other organisms. The most common symbiotic association is with hard, reef-building (or hermatypic) corals, although zooxanthellae can also be found living inside the tissue of soft corals, jellyfish, giant clams and nudibranchs.

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Macroalgal species are divided among three large groups that are named according to the colour of their dominant photosynthetic and accessory pigments: red (Rhodophyta), green (Chlorophyta) and brown (Phaephyta).

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Rising levels of atmospheric carbon dioxide from fossil fuel combustion and deforestation is gradually altering the chemistry of the oceans, making seawater more acidic. The increased acidity has profound implications for all life on Earth, through its likely impacts on plankton, which is the basis of almost all marine food webs. It may also significantly affect the future of the Great Barrier Reef and other coral reefs. Ocean acidification and global warming are two very different, but equally important, spin-off effects of increasing atmospheric carbon dioxide concentrations.
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Crustose coralline algae (CCA) are rock-hard calcareous red algae that fulfill two key functional roles in coral reef ecosystems: they contribute significantly to reef calcification and cementation, and they induce larval settlement of many benthic organisms.

A study of CCA cover on the Great Barrier Reef (GBR) shows strong differences in cover across the Continental Shelf. Mean CCA cover is <1% on the inner third of the GBR, compared to >20% on the outer half of the shelf. CCA cover is also affected by the amount of sediment deposited, water clarity, and the steepness of the reef slopes. Within each cross-shelf zone, the cover of CCA is higher on reefs with low sediment deposits than on reefs with high levels of sedimentation. On the inner third of the shelf, the most sediment-exposed reefs are unsuitable habitats for most CCA. This inverse relationship between CCA and sediment has implications for the recruitment of CCA-specialised organisms, and for the balance between reef accretion and erosion.

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In July 1989 the Australian Government funded a four year environmental study of the Torres Strait marine environment. This study, the Torres Strait Baseline Study, was instigated in response to concerns expressed by Torres Strait Islanders, commercial fishermen and scientists about possible effects on the marine environment of the Torres Strait from mining operations in the Fly River catchment area of Papua New Guinea.

This article is a collection of publications and data associated with this study.

This gallery highlights some the scenery of Torres Strait. Much of the photos are taken from helicopter.

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