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There are five stocks of Shortspined Sea Urchin in Australia. Two stocks are classified as Sustainable, one is Undefined and two are Negligible.

Photo credit: Matt Testoni

The Shortspined Sea Urchin, Heliocidaris erythrogramma,is endemic to Australia and distributed along protected or moderate energy rocky reefs and seagrass beds in temperate and sub-tropical waters from Western Australia to southern Queensland and around Tasmania [Kailola et al. 1993; Williamson 2015; Keesing 2020]. Two subspecies of the Shortspined Sea Urchin have been identified, H. erythrogramma erythrogramma and H. erythrogramma armigera, with the latter occuring in Western Australia [Binks et al. 2011]. Commercial catches of only H. erythrogramma erythrogramma have been reported. 

The Shortspined Sea Urchin can be found to depths of 35 m, but is most abundant in shallow waters < 20m in bays and estuaries, sometimes forming barrens [Pederson and Johnson 2008; Bell et al. 2023]. Lower abundances are observed in highly exposed sites, such as those along the southern and south-west coasts of Tasmania that are dominated by bull kelp habitat [Keesing 2020]. Shortspined Sea Urchins have a hard shell (test) surrounding the soft tissue (such as the dermis, podia, pedicellariae, and gonads), pointed primary spines (10–25 mm in length) and blunt secondary spines [Kailola et al. 1993]. The test diameter is generally < 90mm [Clark 1946] but in Tasmania larger individuals have been recorded up to 125mm test diameter (Growns & Ritz 1994). The Shortspined Sea Urchin has a short pelagic larval duration of three to five days and has limited dispersal capacity [Williams and Anderson 1975]. Significant population differentiation occurs at spatial scales of 1000 kms or less, with differences in mtDNA genotypes between central New South Wales (Sydney and Jervis Bay), Victoria (Port Phillip Bay) and Tasmania (Hobart) [McMillan et al. 1992].

Given the knowledge regarding stock structure and different jurisdictional management objectives, this species is assessed here at the jurisdictional level—New South Wales, Tasmania, Victoria, South Australia and Western Australia.

Victoria

Shortspined Sea Urchins are distributed throughout Victoria, but only harvested commercially in the eastern management zone, from Lakes Entrance to the NSW border, and in Port Phillip Bay. Landings in both fisheries have been variable through time, reaching up to nearly 40 t and 50 t in the eastern zone and Port Phillip Bay fisheries respectively [Bell et al. 2023]. Landings were 8t in the eastern zone and 36.5 t in Port Phillip Bay in 2020–21. Shortspined Sea Urchins are also harvested by recreational fishers and although the landings are not known, they are likely to be low in comparison to commercial catches in both locations.

In eastern Victoria, Shortspined Sea Urchin catch rates have remained relatively stable through time, reaching historic highs in 2021–22 [Bell et al. 2023]. Catch rates in Port Phillip Bay are lower, and more variable, with anecdotal reports by divers suggesting they are influenced by water clarity, algal growth and, as is usual in urchin fisheries, row quality, which tends to be more variable in Port Phillip Bay. Nevertheless, catch rates show no declining trend and were also the highest on record in 2021–22 [Bell et al. 2023]. In addition, large portions of Port Phillip Bay contain extensive Shortspined Sea Urchin barrens with very high densities that are not valuable to fisheries due to poor roe quantity and quality. As such, it is possible that the fishery could reach maximum production (i.e., catch as many urchins with marketable roe as is financially viable) without posing a risk to the stock as a whole [Bell et al. 2023].

The above evidence, including low overall catches, stable catch rates and market constraints, indicates that the biomass of this stock is unlikely to be depleted and that recruitment is unlikely to be impaired. Furthermore, the above evidence also indicates that the current level of fishing mortality in Victoria is unlikely to cause the stock to become recruitment impaired.

On the basis of the evidence provided above, Shortspine Sea Urchin in Victoria is classified as a sustainable stock.

Shortspined Sea Urchin biology. [Keesing 2020]

Distribution of reported commercial catch of Shortspined Sea Urchin.

New South Wales – Indigenous (Management Methods). https://www.dpi.nsw.gov.au/fishing/aboriginal-fishing

Tasmania – Living Marine Resources Management Act 1995. https://www.legislation.tas.gov.au/view/html/inforce/current/act-1995-025

Victoria – Indigenous (Management Methods). A person who identifies as Aboriginal or Torres Strait Islander is exempt from the need to obtain a Victorian recreational fishing licence, provided they comply with all other rules that apply to recreational fishers, including rules on equipment, catch limits, size limits and restricted areas. Traditional (non-commercial) fishing activities that are carried out by members of a traditional owner group entity under an agreement pursuant to Victoria’s Traditional Owner Settlement Act 2010 are also exempt from the need to hold a recreational fishing licence, subject to any conditions outlined in the agreement. Native title holders are also exempt from the need to obtain a recreational fishing licence under the provisions of the Commonwealth’s Native Title Act 1993.

Commercial catch of Shortspined Sea Urchin - note confidential catch not shown.

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