This eco-narrative forms an initial description of the physical and biological features of Arafura Marine Park, located north-east of Darwin. The marine park contains a gently sloping broad shelf that grades to a series of canyons that connect the shelf to the continental slope. Seabed mapping and biodiversity surveys were undertaken by the Marine Biodiversity Hub in November 2020. The survey targeted two areas: Money Shoal, a shallow reef habitat (10 – 60 m deep) that supports corals, sponges and a diverse fish community in clear waters; and Pillar Bank on the outer shelf (150 – 200 m deep) which is characterised by a complex seabed of large ridges, valleys and plains, with turbid waters, muddy seabed and a comparatively sparse seabed biota. The region is characterised by strong tidal flows and a connection to waters delivered by the regions mesoscale currents. Nutrient levels are relatively low across most of the park, with localised higher nutrient levels close to the coast.
Money Shoal, Arafura Marine Park: An eco-narrative
Abstract:
This online article is a summary of one in a series of eco-narrative documents that synthesise our existing knowledge of Australian Marine Parks. Eco-narratives are intended to enable managers and researchers to ascertain the ecological characteristics of each park, and highlight knowledge gaps for future research focus. The information in this eco-narrative forms an initial characterisation of the physical, oceanographic and biological character of Arafura Marine Park, with a focus on results from a biodiversity and mapping survey undertaken by the NESP Marine Biodiversity Hub in 2020. This survey targeted two areas in the marine park: Money Shoal as an example of shallow coral reef habitat, and Pillar Bank as an example of a deeper water mixed seabed environments. This article focuses on survey results from Money Shoal.
This fly-through video explores the seabed environments within Arafura Marine Park, offshore northern Australia. In November 2020, Geoscience Australia and the Australian Institute of Marine Science completed a voyage to map and characterise two areas of the park, Money Shoal and Pillar Bank. Money Shoal is a shallow carbonate reef within the southern part of the park that supports a diverse range of corals and an abundant fish community, including reef sharks and grouper. In contrast, Pillar Bank is in deeper water (150 – 200 m) on the outer shelf and is characterised by sparse benthic communities of filter feeders on local rock outcrop and a relatively low diversity of fish. Funding for the survey was provided by the Australian Government’s National Environmental Science Program Marine Biodiversity Hub, with co-investment by GA and AIMS.
This technical report presents preliminary results and observations of a seabed mapping and biodiversity survey of Arafura Marine Park within the North Marine Park network, undertaken in 2020 by the Australian Institute Marine Science and Geoscience Australia. The primary audience includes researchers and managers of the North Marine Parks and traditional owners of Sea Country in the Arafura Sea region. The objective of the survey was to collect field data to build baseline information by characterising benthic habitats in shelf waters of Arafura Marine Park that will support ongoing monitoring of the park. Bathymetry mapping and underwater imagery were collected in two areas of the park, Money Shoal on the inner continental shelf and Pillar Bank on the outer shelf. These data reveal that Money Shoal supports a diverse shallow water coral and demersal fish community as evidence for the conservation values of the marine park, and which suggest it is unique within its regional setting. Pillar Bank, in contrast, is clearly a different habitat, but is an extensive area within the park that supports benthic communities on hard substrate, albeit sparse in their distribution. Further analysis will be undertaken to quantify the abundance and diversity of these biological communities and to better understand the influence of environmental gradients across the marine park. These new data provide detailed insights into the distribution of sediment-dominated and hardground habitat within Arafura Marine Park, providing a baseline for the ongoing management of the benthic conservation values of this marine protected area.
