true

ISRA FACTSHEETS

AUSTRALIA AND SOUTHEAST INDIAN OCEAN

ISRA FACTSHEETS

AUSTRALIA AND SOUTHEAST INDIAN OCEAN

Southeast Australian Coastal Corridor ISRA

64/158

Southeast Australian Coastal Corridor ISRA

Southeast Australian Coastal Corridor

Summary

Southeast Australian Coastal Corridor is located in Australia in the states of New South Wales, Victoria, Tasmania, and the Jervis Bay Territory. This coastal area comprises continental shelf waters from Newcastle (New South Wales) in the north to Bass Strait and northeast Tasmania in the south. The habitat is characterised by rocky reefs and soft substrates. It is influenced by the East Australian Current that transports warm water southwards through much of the area, and by tide and wind driven surface currents in Bass Strait. Within this area there are: areas important for movement (Port Jackson Shark Heterodontus portusjacksoni).

Southeast Australian Coastal Corridor

Southeast Australian Coastal Corridor

DESCRIPTION OF HABITAT

Southeast Australian Coastal Corridor is located in Australia, in the states of New South Wales, Victoria, and Tasmania, and the Jervis Bay Territory. This movement area stretches from Newcastle in the north via Sydney, Jervis Bay, and Narooma to Bass Strait. It is a coastal area and the shelf is narrow in the north before widening in Bass Strait. It comprises the Gippsland Shelf and the Bassian Ridge (Harris et al. 2003). The habitat is characterised by continental shelf waters, rocky reefs, and sandy substrates (Harris et al. 2003).

The area is influenced by the East Australian Current (EAC) that carries warm water southward along Australia’s east coast (Ridgeway & Hill 2009). The EAC is a dynamic western boundary current, with mesoscale eddies influencing current strength and direction. The flow is seasonally stronger in the austral summer, and the separation location, where the EAC turns eastward into the Tasman Sea, also moves seasonally (Ridgeway & Hill 2009). In Bass Strait, wind and tide driven surface currents influence the area (Jones 1980).

This Important Shark and Ray Area is benthic and is delineated from inshore and surface waters (0 m) to 100 m based on the bathymetry of the area.

CRITERION C

SUB-CRITERION C4 – MOVEMENT

Southeast Australian Coastal Corridor is an important movement area for one shark species.

Port Jackson Sharks regularly migrate through this area, connecting winter breeding sites in the north with summer feeding areas in the south (Bass et al. 2016; L Poirier unpubl. data 2025). A total of 181 individuals were tagged with passive acoustic transmitters and monitored on ~260 receivers within this area between July 2012–July 2024. Many additional receivers in Australia’s Integrated Marine Observing System (IMOS) are located along Australia’s coast, with particularly high density along the east coasts of New South Wales and Queensland, and these would also detect tagged Port Jackson Sharks. Most individuals were tagged in Jervis Bay (n = 97), followed by Sydney (n = 64) and Port Stephens (n = 20) in New South Wales. The sex ratio was slightly skewed towards males, with 89 males, 72 females, and 20 of unknown sex. A movement network identified the number of times tagged animals moved between areas (i.e., ‘moves’) and how many unique individuals made each move (L Poirier unpubl. data 2025).

Port Jackson Shark movements supported a corridor from Newcastle in the north, via Sydney, Jervis Bay, and Narooma to Bass Strait (L Poirier unpubl. data 2025). Most moves were detected within Sydney–Botany Bay and Sydney Harbour (n = 630 and 626 moves per direction, respectively), followed by Narooma to Jervis Bay (n = 114) and return (n = 111), and Sydney to Narooma (n = 88) and return (n = 73). Almost a third of tagged individuals moved from Narooma to Jervis Bay (n = 52 individuals) and returned (n = 47), while 34 individuals moved from the Sydney region to Narooma and 27 individuals moved in the opposite direction. Connectivity was strongest between Sydney, Jervis Bay, and Narooma. However, 11 Port Jackson Sharks also connected eastern Victoria with these sites while four individuals moved to Bass Strait in Tasmania. Tracked Port Jackson Sharks exhibited strong seasonality, being detected in the Sydney region and Jervis Bay mostly from July–October, while the peak in Narooma was in April–June and October–December, and between February–May in Victoria (L Poirier unpubl. data 2025). This corroborates that they move from winter/spring breeding areas in the north to summer/autumn feeding sites in the south (Bass et al. 2016).

Connectivity with Victoria and Bass Strait is further supported by additional evidence. First, it is worth noting that the acoustic detections around Cape Baron Island in Bass Strait ceased because the receiver line was decommissioned in 2015 after just three years of operation. The majority of sharks were tagged after this date. It is conceivable that many more migrate to this location and in Bass Strait more broadly. Second, in August 2018 and 2024, aggregations of 1,000+ female Port Jackson Sharks were found in the Hogan-Kent Islands ISRA in Bass Strait resting on the mesophotic reefs in 65 m depth by an autonomously operated vehicle (AUV) and remotely operated vehicles (ROVs) (Barrett et al. 2020; University of Tasmania 2024; NESP 2025). These females may represent those individuals taking a year off migration to build energy reserves. Third, a historical study externally tagged 513 Port Jackson Sharks in the Sydney region between 1962–1974 and 18 were recaptured along the east coast as far south as Tasmania (O’Gower & Nash 1978; O’Gower 1995). Seven of these individuals were captured off the coast of East Gippsland and Wilsons Promontory in Victoria, and two off Flinders Island and Cape Naturaliste in northeast Tasmania. Individuals from the east coast are never detected west of Wilsons Promontory and genetic evidence as well as life-history data suggest the east and southwest populations are distinct (Tovar-Ávila et al. 2007; R Leite et al. pers. comm. 2025). Collectively, the data suggest that Port Jackson Sharks migrate down the east coast of Australia at the end of the winter breeding season and may use the series of islands linking the mainland at Wilsons Promontory with northeast Tasmania. They feed in deeper waters around Bass Strait during the summer and return to breeding aggregation sites in the winter.

Southeast Australian Coastal Corridor

SUBMIT A REQUEST

ISRA SPATIAL LAYER REQUEST

To make a request to download the ISRA Layer in either a GIS compatible Shapefile (.shp) or Google Earth compatible Keyhole Markup Language Zipped file (.kmz) please complete the following form. We will review your request and send the download details to you. We will endeavor to send you the requested files as soon as we can. However, please note that this is not an automated process, and before requests are responded to, they undergo internal review and authorization. As such, requests normally take 5–10 working days to process.

Should you have questions about the data or process, please do not hesitate to contact us.

    * indicates required

    Industry or sector (*)

    Under the terms and conditions of our User License Agreement , full and appropriate acknowledgement is required in any materials and publications derived from the data (and copies should be sent to the IUCN SSC Shark Specialist Group through the contact form). For any publications making substantial use of the data, the ISRA welcomes the opportunity for co-authorship, collaboration, and to comment prior to publication.


    Furthermore, we need to know whether you are a commercial or non-commercial user. Non-commercial includes scientific research, education or conservation. Commercial is defined as follows: any use by, on behalf of, or to inform or assist the activities of a commercial entity (that operates ‘for profit’) or use by a non-profit for the purposes of revenue generation

    Type of use(*):

    Please specify which layer (ex. all layers, layers within a specific Region, layers within a Jurisdiction or a single ISRA): Purpose (*):

    Please provide a description of how you intend to use the ISRA GIS Dataset. The more details you provide, the faster we can respond to your request. We may require further clarification prior to providing access. (min. 100 characters – max 1,000 characters)



    File format request (*)

    By providing your personal data, you consent to its processing as described below. The IUCN SSC Shark Specialist Group will use the information you provide on this form to send the documents you requested. You can change your mind at any time by writing to the ISRA Data Coordinator www.sharkrayareas.org/contact. All personal details provided will be treated with respect. For any information you can visit our Privacy Policy.
    Please read the User License Agreement and ISRA Layer Metadata Description

    This form uses Google reCaptcha to reduce spam. Privacy - Terms