Hard undifferentiated coral on consolidated substrate in shallow to deep water

Long description

Subtidal hard coral on consolidated substrate (e.g. fringing reefs, shelf reefs and as coral communities on rock) in shallow (0 to 10 metres) to deep water (to 30 metres), where structure is not differentiated.

There are distinct ecological differences between coral ecosystems growing on rock, fringing reefs and shelf reefs. The majority of fringing reefs of the coastal Great Barrier Reef began their growth on unconsolidated sediments and few originated on rock[5]. For further discussion on the different types of fringing reef, see consolidated/intermediate calcareous reef including coral platform (type 100).

Typically coral fringing reefs and shelf reefs include mixtures of hard and soft corals and macroalgae, which can grow in distinct zones horizontally across a reef and vertically in depth, alternating with unconsolidated sediments and consolidated rock. Hard corals are a critical component of fringing reefs and shelf reefs as they actively lay down carbonate, creating their own consolidated substrate.

Special values

The values of Queensland’s coral reefs are internationally recognised in the World Heritage and Ramsar conventions. The Outstanding Universal Value of the Great Barrier Reef World Heritage area is based on four criteria (vii), (viii), (ix), (x). The Ramsar convention also includes coral reefs as one of its wetland types which make up part of a site’s ecological character (a combination of the ecosystem components, processes and services of the wetland). The Great Sandy Strait Ramsar wetland also includes coral reefs (e.g. Woody and Round Island reefs, coral communities at Little Woody Island, and soft corals on coffee rock reefs). Shoalwater and Corio Bays Ramsar wetland and the Moreton Bay Ramsar wetland also includes fringing coral reefs.

Hard corals create carbonate consolidated substrate that is living space for a range of biota. They create structural substrates valued for their recreational (snorkelling, spear-fishing, angling), tourism and aesthetic values. They also occur on rocky reefs at high latitudes. They form important fish habitats for a variety of coral-dwelling fish species and support major line fin fisheries) and sharks.

Coral reefs and communities also stabilise the shoreline preventing erosion and protect the coastline by moderating the impacts of waves[4].

Diagnostic attributes

Inundation 'Subtidal'

Benthic depth 'Shallow (0-10m)', 'Deep (10-30m)'

Consolidation 'Consolidated'

Structural macrobiota 'Hard coral – undifferentiated', 'Hard coral – branching', 'Hard coral – bushy', 'Hard coral – massive', 'Hard coral – submassive', 'Hard coral – vase/foliose', 'Hard coral – plate/table', 'Hard coral – encrusting', 'Hard coral – mixture of structures'

Qualifiers

The Cover qualifier is relevant as the percentage of hard coral substrate is an important indicator for monitoring of coral condition on coral reefs and communities.

Distribution

In general mainland fringing with hard coral reefs occur around the Whitsundays and Cairns northward and inshore reef growth of the southern Great Barrier Reef (south of 21 degrees S) is considered poor, related to turbidity controls on coral carbonate production and accumulation[5]. Hard corals grow on rocky reefs and as a veneer on old carbonate reefs in Moreton Bay[1].

The following relates to distribution of this ecosystem type within the Central Queensland mapping area:

• In Central Queensland hard corals occur on islands of the Keppels group, along Curtis and Facing Island and in Port Curtis. Their known extent is on fringing reefs at Pancake Creek, in patches of coral community on the boulder Woongarra coast, on Four Mile Reef, and as a series of fringing carbonate reefs along the Hervey Bay mainland coastline and on Round and Woody Islands in the Great Sandy Strait.

Comments

Water temperature is critical to all corals as they are sensitive to extremes of heat and cold, resulting in bleaching due to the loss of endosymbiotic dinoflagellates (e.g. zooxanthellae) and therefore the ability to photosynthesise[2].

Benthic rugosity of coral reefs is important for creating three-dimensional living space for biota including fish, and allowing more shading which can protect corals during bleaching events[3].

Additional Information

Protecting the Great Barrier Reef - Queensland Government

Coral - Department of Environment, Science and Innovation

Coral reefs - Queensland Museum

The Reef - Great Barrier Reef Marine Park Authority

Corals of the World

Great Barrier Reef - UNESCO

Nationally (DIWA) and internationally important (Ramsar) wetlands - WetlandInfo

Coral Indicators for the 2017 Gladstone Harbour Report Card - Australian Institute of Marine Science

Reef Report Card 2016 - Queensland Government

Great Barrier Reef Outlook Report - Great Barrier Reef Marine Park Authority

Monitoring inshore reefs - Australian Institute of Marine Science

Reef Check Methods - Reef Check Australia

Coral reefs - Museum of Tropical Queensland

Remote Sensing Research Centre - The University of Queensland

References

1. ^ Fellegara, I & Harrison, PL (2008), 'Status of the subtropical scleractinian coral communities in the turbid environment of Moreton Bay, southeast Queensland', Proceedings of the Thirteenth International Marine Biological Workshop: The Marine Fauna and Flora of Moreton Bay, Queensland, pp. 277-291.
2. ^ Hoegh-Guldberg, O (1999), 'Climate change, coral bleaching and the future of the world's coral reefs', Marine and Freshwater Research. [online], vol. 50, no. 8, p. 839. Available at: http://www.publish.csiro.au/?paper=MF99078 [Accessed 11 June 2019].
3. ^ Muir, P, Wallace, C, Bridge, TCL & Bongaerts, P (25 February 2015), 'Diverse Staghorn Coral Fauna on the Mesophotic Reefs of North-East Australia', PLOS ONE. [online], vol. 10, no. 2, p. e0117933, ed. S C A Ferse. Available at: http://dx.plos.org/10.1371/journal.pone.0117933 [Accessed 19 March 2019].
4. ^ Siebentritt, M (2016), Understanding sea-level rise and climate change, and associated impacts on the coastal zone. CoastAdapt Information Manual 2.
5. ^ a b Smithers, SG, Hopley, D & Parnell, KE (2006), 'Fringing and nearshore coral reefs of the Great Barrier Reef: episodic Holocene development and future prospects', Journal of Coastal Research, pp. 175-187.

Last updated: 12 July 2019