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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.

Tasmania

The commercial harvest of Shortspined Sea Urchin in Tasmania can be traced back to the 1960s, with a sustained fishery commencing in the 1980s [Hayward 2013]. Commercial catches peaked in the late 1980s with 250 dive licenses contributing to 359 t harvested [Sanderson et al. 1996] however, landings have since gradually declined. In 2005 a cap on the maximum number of commercial dive licenses was introduced, currently 53 licenses, with each license allowing harvest of both Shortspined and Longspined sea urchins (Centrostephanus rodgersii), as well as periwinkles (Lunella undulata). Management of Shortspined Sea Urchin includes a TAC of 175 t divided between five fishing zones, a minimum TD of 80 mm (from September 1st 2023) which has increased several times over over the last few years. Size (TD) at 50% maturity is estimated at 40.1 mm at 2.5 years of age, with size plus 1–4 years of growth post maturity being 52.5 (50.5–54.3) mm, 64.2 (59.9–68.3) mm, 75.0 (68.1–81.8) mm and 85 (75.0–81.8) mm, respectively (averaged across 11 eastern and southern Tasmanian sites; Keane, unpublished data). Therefore, the current size limit allows for approximately 3 years of spawning before urchins enter the fishery, up from 1 year when the size limit was 60 mm. Variability in growth is evident, driven by habitat and urchin density as evidenced in previous localised sudies [Pederson and Johnson 2008; Sanderson et al. 1996].

Catch Caps within zones have also been implemented over the last few seasons to disperse effort and to minimise risk of localised depletion to valuable stocks. Catch rates are stable within zones and catch cap areas. Areas with an overabundance of urchins of lower value (poor roe quality) still remain and a dispersion of effort to such areas via is hoped to improve roe quality over time as densities decrease [Sanderson et al. 1996]. There are also Shortspined Sea Urchin barrens in some areas with unmarketable roe.

Shortspined Sea Urchin is traditionally the most valuable and, therefore, preferred target species harvested by the commercial dive fishery (CDF) in Tasmania. The fishing season is generally from late September until December when the roe is at the highest quality and maximum profitability. This season is the complement to the Longspined Sea Urchin season which takes place from December to June. Tasmanian Shortspined Sea Urchin roe is primarily shipped to established markets in Sydney and Melbourne

Management actions in recent years were aimed to protect egg production through increasing size limits and dispersing effort spatially by introducing catch caps. The above evidence, including stable catch rates, market constraints and managaement action 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 Tasmania is unlikely to cause the stock to become recruitment impaired.

On the basis of the evidence provided above, Shortspined Sea Urchin in Tasmania 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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