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Over recent decades, the Longspined Sea Urchin has extended its range southwards to VIC and TAS, reflecting the increasing influence of the south-flowing Eastern Australian Current in those latitudes. At high densities, Longspined Sea Urchins can damage kelp habitats through overgrazing, leading some jurisdictions to pursue urchin removal programs. Longspined Sea Urchin stock structure is uncertain and management arrangements differ across jurisdictions, so this assessment is presented at the jurisdictional level. Longspined Sea Urchin are classified as sustainable in NSW, TAS and VIC.

Over the last several decades the Longspined Sea Urchin, Centrostephanus rodgersii, has undergone a range extension to Victoria and Tasmania from NSW due to extensions in the warm East Australia Current brought about by climate change [Johnson et al. 2005, Ridgway 2007, Ling 2008].

The strength of connectivity between regions and the species' capacity for self-recruitment at the extremes of its distribution remain poorly understood and are currently under investigation as part of an FRDC project "Larval dispersal for Southern Rock Lobster and Longspined Sea Urchin to support management decisions".

Understanding Longspined Sea Urchin population structure has been of particular importance as high urchin densities can damage kelp forests through overgrazing [Ling et al. 2009, Johnson et al. 2011, Marzloff et al. 2016] and this has resulted in notable habitat changes in areas of range extension. Due to this impact and the range-extending nature of this species, management measures are being actively pursued to decrease the population density in some jurisdictions.

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

Victoria

Victoria

The Longspined Sea Urchin fishery is confined to the Eastern Zone, extending from east of the coastal port of Lakes Entrance to the Victorian–NSW border. An assessment in 2019 found that landings and fishing effort had both showed an increasing trend in recent years since a low in the 2015 quota year [Conron et al. 2020].

CPUE has remained very stable at ~175 kg/hr for the last four quota years with a slight decrease over the last year [Conron et al. 2020]. However, CPUE is likely to be more reflective of the availability of urchins with roe of marketable quality rather than the species' abundance as a whole. This is illustrated by an increase in abundance of about 80 per cent observed from fishery independent surveys over the same period following a decrease (probably as a result of targeted urchin reduction programs to mitigate range expansion and restore kelp habitat from barrens) of about one third over the preceding two years [Conron et al. 2020]. This species is very abundant on barrens in deeper waters, however, commercial fishing effort is typically focused in shallower areas and where kelp habitat transitions to barrens. 

Catch, effort, and CPUE trends for this species are largely reflective of market demand and can be influenced by changes in the availability of urchins with marketable roe. 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 [Conron et al. 2020]. The above evidence indicates that the biomass of this stock is unlikely to be depleted and that recruitment is unlikely to be impaired. The above evidence also indicates that the current level of fishing mortality is unlikely to cause the stock to become recruitment impaired.

Based on the available evidence the Eastern Victorian Longspined sea urchin is classified as a sustainable stock.

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

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.

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