Report to the Department of Sustainability, Environment, Water, Population and Communities, by Daniela Ceccarelli, Oceania Maritime Consultants. January 21st, 2011.

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• Research and Monitoring in Australia’s Coral Sea: A Review

Executive summary

The Coral Sea is an international body of water that lies between the east coast of Australia, the south coasts of Papua New Guinea and the Solomon Islands, extends to Vanuatu, New Caledonia and Norfolk Island to the east and is bounded by the Tasman Front to the south.

The portion of the Coral Sea within Australian waters is the area of ocean between the seaward edge of the Great Barrier Reef Marine Park (GBRMP), the limit of Australia’s Exclusive Economic Zone (EEZ) to the east, the eastern boundary of the Torres Strait and the line between the Solitary Islands and Elizabeth and Middleton Reefs to the south.

Within the Australian boundaries of the Coral Sea is the Coral Sea Conservation Zone, which lies between the seaward edge of the GBRMP and the limit of Australia’s EEZ, and shares the GBRMP’s northern and southern boundaries (see map on Page 12).

This review considers the entire Australian portion of the Coral Sea.

The Coral Sea is considered environmentally significant due to the relatively undisturbed nature of its natural systems, its ecological distinctiveness, the provision of habitat for species of conservation significance and its role in connecting the South Pacific islands and the Great Barrier Reef (GBR).

Four Commonwealth Marine Protected Areas (CMPAs) are located in the Coral Sea: the Lihou Reef National Nature Reserve (Lihou Reef), the Coringa-Herald National Nature Reserve (Coringa-Herald), the Solitary Islands Marine Reserve (SIMR) and the Elizabeth and Middleton Reefs Marine National Nature Reserve (Elizabeth and Middleton).

This review synthesises all the past research conducted in the Coral Sea, identifies knowledge gaps and offers options for filling those gaps.

With increasing global concern about the future stability of marine systems, prioritising areas for targeted future research will be crucial if scientists are to make informed predictions about possible changes and impacts that can direct management and conservation actions.

A total of 303 separate documents describing research conducted in the Coral Sea were identified and reviewed.

The earliest document found was a biogeographic study on echinoderms from 1957, but regular research expeditions began to take place in the 1970s.

The total number of studies per year began to increase in the late 1990s, and 69.9% of all studies have taken place in the last decade.

Over one-third (38.6%) of the reviewed studies covered large Coral Sea areas; these were mostly large-scale oceanography studies, literature reviews compiled as part of the Bioregional Marine Planning process and fish tagging research projects.

Other studies that covered large areas nevertheless were concentrated in either the northern, northwestern, eastern, southern or western Coral Sea.

Coral reef research accounted for 58.2% (176) of the documented studies, in both shallow and deep environments.

Of these, the reefs and cays of Coringa-Herald were the most frequently studied, followed closely by Osprey Reef.

Some studies included multiple reefs, but many of these were simply series of collections, rather than rigorous comparative studies.

Most reefs in the Coral Sea remain virtually unexplored. For instance, there is not enough information to even present a comparison of coral cover across more than three Coral Sea reefs.

Marine ecological studies dominated the available research material. Fisheries research, primarily associated with tuna and billfish targeted by the Eastern Tuna and Billfish Fishery, was also well-represented.

Large, international research expeditions to study the oceanography and geology of the Coral Sea have generated a reasonable body of research, while disciplines such as history and heritage, chemistry, research and monitoring and the study of human use were represented by only a few documents each.

Overall patterns of research focus suggests that the Coral Sea’s reefs have been the principal focus of biological and ecological studies, while the wider Coral Sea has attracted a more diverse range of disciplines.

In terms of publications and reports, fisheries research made up almost half of the volume of available studies that focused on the broader Coral Sea area, followed by literature on climate and oceanography research.

Among the reefs, Osprey Reef has attracted the most diverse range of studies, but biological and ecological research still comprised more than three quarters of the available material.

The four Reseves and the northern Coral Sea reefs have attracted almost exclusively ecological research, while the southern reefs, represented by only 14 studies, have been the focus of history and heritage research.

The oceanography, bathymetry, and geology of the Coral Sea are relatively well-known at large scales. Little detail exists for smaller-scale processes within the Coral Sea, and most of the individual topographic features are not well understood.

Studies of interactions between hydrodynamic patterns and processes, geomorphologic features and ecological characteristics are still very rare. Much more work is needed to fully understand the levels of connectedness and isolation between habitats, the location of larval sources and sinks, and the pathways of dispersal.

Furthermore, there is very limited understanding of the patterns and processes that underpin ecosystem health and the potential for recovery from disturbances.

These issues are important for management and conservation, as the placement of marine protected areas in the future will need to take into account patterns of connectivity, dispersal trajectories, source and sink reefs and the distribution of biodiversity.

Despite the dominance of ecological and biological studies in this review, the understanding of ecological patterns and processes in the Coral Sea remains patchy.

Especially large gaps exist in the knowledge about pelagic ecosystems and deep-sea demersal habitats and communities.

Shallower coral reef environments would also benefit from further ecological research.

Both temporal and spatial coverage of coral reefs has lacked integration, resulting in two major problems: 1) the spatial extent of ecological surveys has essentially been limited to three reef systems, and 2) on those three reef systems, successive surveys have almost always lacked consistency.

Together, these two short-comings mean that it is virtually impossible to detect large-scale patterns or long-term trends.

Both are crucial for management because they identify areas of conservation value and indicate temporal dynamics and recovery potential for key groups of organisms.

The primary options for research to fill the gaps identified in this review include:

• Sources of existing data that may assist in filling gaps; prioritize the collation, analysis and reporting of these datasets.
• While large-scale oceanographic features are known and well-documented, there is a lack of knowledge of finer-scale hydrodynamics linking habitats within the Coral Sea. A hydrodynamic model specifically for the Coral Sea will help to locate larval sources and sinks, migration and dispersal pathways, levels of connectivity and isolation and areas of connectivity with other systems.
• Predictions of future climate change impacts in all areas of the Coral Sea will help to identify areas of resilience and vulnerability.
• Ecological baseline studies will ensure that there is at least basic ecological knowledge for key habitats in the Coral Sea, including open ocean, deep-sea demersal, seamounts and reefs. New data collected should contribute to an understanding of ecological function and health (e.g. by collecting data on functional groups such as grazers, predators, habitat builders, etc., and measures of ecosystem health such as symbioses and disease) trophic relationships, and genetic characteristics.
• Identify areas of feeding or breeding significance for migratory species, such as the location of spawning aggregations. Identify the extent to which the Coral Sea may be supplying recruits to the GBR.
• Links between ecological information and physical data are still weak. Together with the identification of key functional groups and measures of ecosystem resilience or vulnerability, this will direct future research, monitoring and management activities to the correct places – for instance: establishing indicators for monitoring, specific areas of value or concern to be more highly protected, areas for active management such as pest eradication or control, and genetic connectivity between areas.
• Future conservation strategies will be assisted by the decision of whether to protect “strong” or “weak” areas, or both. This means identifying and scoring Coral Sea areas that may be classified as “strong” (e.g. high resistance or resilience to disturbance, intact trophic structure, stable environmental parameters, good recovery potential, high abundance and diversity of key organisms, high connectivity to larval sources) or “weak” (e.g. low resistance or resilience to disturbance, elements of the trophic structure low or missing – e.g. through historic overfishing of predators or invertebrates, poor recovery potential, low abundance and diversity of key organisms, low connectivity to larval sources). These considerations are most usefully set into a risk assessment-type decision-making framework.
• A temporally consistent system of environmental / ecological monitoring and compliance monitoring for each broad habitat remains to be designed. If funds are short, compliance monitoring may be more important in some cases than environmental monitoring.
• Many of the information gaps in the Coral Sea are due to its remoteness. Assess the viability of establishing a ‘Coral Sea Research Station’, through liaison with the Bureau of Meteorology, at the existing weather station on Willis Island. Its existing infrastructure and central location could provide a suitable base from which to launch rigorous and ongoing research into the future.
• Regularly update this review with new information, to provide a central database where new research on the Coral Sea can easily be deposited, stored and queried. As research in the Coral Sea requires a permit, there is an avenue for attaching a requirement that the data or resulting written material be submitted to the DSEWPaC. Update the EndNote library with linked original electronic documents. The higher the frequency of these updates (e.g. annually), the lower the cost and time expenditure each time.