Coral Luminescence Identifies the Pacific Decadal Oscillation as a Primary Driver of River Runoff Variability Impacting the Southern Great Barrier Reef

This article examines naval surveying voyages undertaken between 1815 and 1860 by Phillip Parker King, Francis Price Blackwood, Owen Stanley and Henry Mangles Denham to discuss the improvements to the navigation of the Inner and Outer shipping routes along the Great Barrier Reef. The Inner Route lay between Australia’s east coast and the western edge of the reefs while the Outer Route was situated in open sea beyond the eastern edge of the reefs. These were some of the most dangerous waters for ships in the Pacific off Australia’s east coast. The article analyses the improvements to both routes resulting from the surveying of the naval commanders referred to above; it explains why the choice between the Inner and Outer routes was difficult to make; and it shows that the Outer Route was increasingly favoured by merchant vessels.

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First record of the genus Umimayanthus from Palau and Micronesia

Marine Biodiversity Records ◽

10.1017/s1755267215001177 ◽

2015 ◽

Vol 8 ◽

Author(s):

Javier Montenegro ◽

Julien Lorion ◽

James Davis Reimer

Keyword(s):

Molecular Markers ◽

Great Barrier Reef ◽

Red Sea ◽

Pacific Islands ◽

New Caledonia ◽

Morphological Characteristics ◽

First Record ◽

Barrier Reef ◽

The Pacific ◽

The Family

Until recently, the only sponge-associated genera in the order Zoantharia wereParazoanthus(family Parazoanthidae),EpizoanthusandThoracactis(family Epizoanthidae), both within the suborder Macrocnemina. The taxonomy of the genusParazoanthus,as originally described, has been undergoing revision since 2010, with several species, genera and even families described. In 2015, multiple molecular markers were used in combination with morphological characteristics to erect the genusUmimayanthusinside the family Parazoanthidae. It included three species described from southern Japan, with other records for some of the species from the Great Barrier Reef, New Caledonia and the Red Sea. However, little is known of its distribution in the Pacific Islands. Here we report on the finding ofUmimayanthusspecimens in Palau, Micronesia, representing the first records for this region. A total of 32 specimens ofUmimayanthuswere collected from seven different locations; eight of the specimens were identified asUmimayanthus chanpuru,while the remaining 24 colonies were only identified to genus level.

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Coral records of reef-water pH across the central Great Barrier Reef, Australia: assessing the influence of river runoff on inshore reefs

Biogeosciences Discussions ◽

10.5194/bgd-11-11443-2014 ◽

2014 ◽

Vol 11 (7) ◽

pp. 11443-11479 ◽

Cited By ~ 3

Author(s):

J. P. D'Olivo ◽

M. T. McCulloch ◽

S. M. Eggins ◽

J. Trotter

Keyword(s):

Great Barrier Reef ◽

River Runoff ◽

River Discharge ◽

Co2 Uptake ◽

Barrier Reef ◽

Transient Effects ◽

Inner Shelf ◽

Phytoplankton Productivity ◽

Water Ph ◽

The Impact

Abstract. The boron isotopic (δ11Bcarb) compositions of long-lived Porites coral are used to reconstruct reef-water pH across the central Great Barrier Reef (GBR) and assess the impact of river runoff on inshore reefs. For the period from 1940 to 2009, corals from both inner as well as mid-shelf sites exhibit the same overall decrease in δ11Bcarb of 0.086 ± 0.033‰ per decade, equivalent to a~decline in seawater pH (pHsw) of ~ 0.017 ± 0.007 pH units per decade. This decline is consistent with the long-term effects of ocean acidification based on estimates of CO2 uptake by surface waters due to rising atmospheric levels. We also find that compared to the mid-shelf corals, the δ11Bcarb compositions for inner shelf corals subject to river discharge events, have higher and more variable values and hence higher inferred pHsw values. These higher δ11Bcarb values for inner-shelf corals are particularly evident during wet years, despite river waters having lower pH. The main effect of river discharge on reef-water carbonate chemistry thus appears to be from higher nutrients driving increased phytoplankton productivity, resulting in the drawdown of pCO2 and increase in pHsw. Increased primary production therefore has the potential to counter the more transient effects of low pH river water (pHrw) discharged into near-shore environments. Importantly however, inshore reefs also show a consistent pattern of sharply declining coral growth that coincides with periods of high river discharge. This occurs despite these reefs having higher pHsw values and hence higher seawater aragonite saturation states, demonstrating the over-riding importance of local reef-water quality on coral reef health.

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East Australian current adjacent to the Great Barrier Reef

Marine and Freshwater Research ◽

10.1071/mf9870671 ◽

1987 ◽

Vol 38 (6) ◽

pp. 671 ◽

Cited By ~ 78

Author(s):

JA Church

Keyword(s):

Great Barrier Reef ◽

Bifurcation Point ◽

Monsoon Season ◽

Surface Flow ◽

Barrier Reef ◽

Surface Shear ◽

Near Surface ◽

Indonesian Archipelago ◽

The Pacific ◽

The Indian Ocean

Hydrographic data from a series of cruises during 1980-1981 are used to determine the circulation in the western Coral Sea region immediately adjacent to the Great Barrier Reef. The data show flow westward towards the Great Barrier Reef, bifurcating just north of 18�S. During the monsoon season (December to February), the bifurcation point moves north to at least 14�s. The geostrophic westward flow has a subsurface maximum at a depth of about 150 m. South of the bifurcation point, the flow is south-eastward on the upper continental slope and north-eastward offshore. North of the bifurcation point, the surface flow and transport (relative to 900 dbar) are northward. However, there is sometimes a south-eastwards near-surface shear. Near the bifurcation point, the surface currents are weak and variable. All of these features of the surface flow are reflected in the paths followed by satellite-tracked drifters. Although the drifters were fixed infrequently, the drifter data indicate the possible presence of small cyclonic eddies in the region of the bifurcation. All of the satellite-tracked drifters went aground in the Great Barrier Reef within 30 days of entering the region offshore from the Reef. The data are consistent with recent models of the wind-driven circulation in the South Pacific that propose that the westward flow bifurcates at about 20�S., with 17 x 106 m3 s-1 flowing through the Indonesian Archipelago from the Pacific Ocean to the Indian Ocean.

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Knowledge Gaps in the Biology, Ecology, and Management of the Pacific Crown-of-Thorns Sea Star, Acanthaster sp., on Australia’s Great Barrier Reef

Biological Bulletin ◽

10.1086/717026 ◽

2021 ◽

pp. 000-000

Author(s):

Morgan S. Pratchett ◽

Ciemon F. Caballes ◽

Christopher Cvitanovic ◽

Maia L. Raymundo ◽

Russell C. Babcock ◽

...

Keyword(s):

Great Barrier Reef ◽

Barrier Reef ◽

Sea Star ◽

Knowledge Gaps ◽

The Pacific

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Coral records of reef-water pH across the central Great Barrier Reef, Australia: assessing the influence of river runoff on inshore reefs

Biogeosciences ◽

10.5194/bg-12-1223-2015 ◽

2015 ◽

Vol 12 (4) ◽

pp. 1223-1236 ◽

Cited By ~ 20

Author(s):

J. P. D'Olivo ◽

M. T. McCulloch ◽

S. M. Eggins ◽

J. Trotter

Keyword(s):

Great Barrier Reef ◽

River Runoff ◽

River Discharge ◽

Barrier Reef ◽

Inner Shelf ◽

Phytoplankton Productivity ◽

Saturation State ◽

Aragonite Saturation ◽

Water Ph ◽

The Impact

Abstract. The boron isotopic (δ11Bcarb) compositions of long-lived Porites coral are used to reconstruct reef-water pH across the central Great Barrier Reef (GBR) and assess the impact of river runoff on inshore reefs. For the period from 1940 to 2009, corals from both inner- and mid-shelf sites exhibit the same overall decrease in δ11Bcarb of 0.086 ± 0.033‰ per decade, equivalent to a decline in seawater pH (pHsw) of ~0.017 ± 0.007 pH units per decade. This decline is consistent with the long-term effects of ocean acidification based on estimates of CO2 uptake by surface waters due to rising atmospheric levels. We also find that, compared to the mid-shelf corals, the δ11Bcarb compositions of inner-shelf corals subject to river discharge events have higher and more variable values, and hence higher inferred pHsw values. These higher δ11Bcarb values of inner-shelf corals are particularly evident during wet years, despite river waters having lower pH. The main effect of river discharge on reef-water carbonate chemistry thus appears to be from reduced aragonite saturation state and higher nutrients driving increased phytoplankton productivity, resulting in the drawdown of pCO2 and increase in pHsw. Increased primary production therefore has the potential to counter the more transient effects of low-pH river water (pHrw) discharged into near-shore environments. Importantly, however, inshore reefs also show a consistent pattern of sharply declining coral growth that coincides with periods of high river discharge. This occurs despite these reefs having higher pHsw, demonstrating the overriding importance of local reef-water quality and reduced aragonite saturation state on coral reef health.

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