Distribution and Habitat Suitability of Threatened and Migratory Marine Species in Northern Australia

The North Marine Bioregion is home to a diversity of threatened and data-poor marine species. In the absence of critical data on species’ distributions, population connectivity, and essential habitat, decision-making to progress the current ‘Developing the North’ agenda has the potential to negatively impact Matters of National Environmental Significance. Following the report of the NESP Marine Biodiversity Hub Project Project A12 – Australia’s Northern Seascape (Phase 1), which highlighted where gaps in knowledge are limiting the ability to understand the potential impacts of future development, Phase 2 of Project A12 – Australia’s Northern Seascape includes a component on modelling and mapping Threatened and Migratory marine species distributions. This was undertaken for 16 priority Threatened and Migratory marine species (Table 1) listed by the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) through a collaborative process with data custodians to compile and analyse existing spatial data. The focus area was the North Marine Region, which consists of the waters offshore from the Northern Territory to the EEZ edge, and east to the coast of Queensland including the northern tip of Cape York and waters of the Gulf of Carpentaria and where possible, we expanded the analysis beyond this region. The objective of the project was to improve the current data-poor species distribution maps held by the Department of Agriculture, Water and the Environment (DAWE) to assist with policy decisions related to these species.
To predict suitable habitat where species are likely to occur, we used a spatial distribution modelling approach (Maxent and GAMM) based on presence data from the compiled spatial datasets (121 in total) for these species and associated, remotely sensed environmental variables. The output is a series of more detailed and data driven distribution maps than are currently available at this scale that will enhance decision-makers’ ability to assess potential impacts of development proposals in Northern Australia under the EPBC Act. Maps of the modelled species distribution (not the raw data) were made publicly available through the NESP Marine Biodiversity Hub’s (MBH) website and the Australian Ocean Data Network (AODN). Where data sharing agreements have allowed (the majority of cases), we have provided a copy of the raw data used in the models to the DAWE for inclusion in the Species Profile and Threats (SPRAT) database that stores information on species and ecological communities listed under the EPBC Act for use in their future management of Threatened and Migratory marine species.