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Ruby Snappers are widely distributed throughout northern Australian waters. There are two biological stocks. The Northern Australia stock encompasses all Australian waters west of Torres Strait (i.e. waters off the NT and WA), while the Eastern Australian stock occurs off the east coast of QLD, extending south into NSW. The Northern Australia stock is sustainable, while the Eastern Australia stock is currently undefined, although the level of catch is very low.

Photo: Stephen Newman, Department of Primary Industries and Regional Development, Western Australia

Andrews et al. [2016] examined the phylogeny of deepwater snappers of the genus Etelis using two mtDNA loci and two nuclear introns. The analyses of Andrews et al. [2016] indicated that species identified as E. carbunculus is comprised of two distinct, non-interbreeding lineages separated by a deep divergence, i.e. it was comprised of two cryptic species, Etelis carbunculus and a larger Etelis sp. (not formally described). Both of these cryptic species exhibit overlapping Indo-Pacific distributions, with E. carbunculus being more widespread across the Indo-Pacific, whereas the larger Etelis sp. is reported mainly from the Indian Ocean and Western Central Pacific [Andrews et al. 2016]. While these two species are morphologically similar, there are differences in the coloration of the upper-caudal fin tip, the shape of the opercular spine, differences in adult body length, body depth, and head length, and otolith morphometrics that can be used to separate the species [Wakefield et al., 2014; Andrews et al., 2016]. These species are now commonly referred to as pygmy ruby snapper (E. carbunculus) and giant ruby snapper (Etelis sp.). The main species landed in northern Australian waters is Etelis sp. (currently undescribed). 

Andrews et al. [2020] investigated the population structure of E. carbunculus and Etelis sp. (as well as Etelis coruscans) across their distributional range in the Indo-Pacific. Andrews et al. [2020] examined a total of 1064 specimens of E. carbunculus from 11 regions, and 590 specimens of E. sp. from 16 regions. Samples of E. carbunculus were analysed using mtDNA and 9–11 microsatellite loci, while E. sp. was analysed with mtDNA only. Etelis carbunculus exhibited low but significant levels of isolation for the Hawaiian Archipelago, and divergence between Tonga and Fiji. Etelis sp. exhibited little structure except a strong pattern of isolation for both Seychelles and Tonga at the edge of their distribution (east and west, respectively). This indicates populations are structured on the wider scale of ocean basins and the capacity for widespread dispersal throughout the Indo-Pacific region. As such, Australian populations of Ruby Snappersare likely to form a single biological stock in the Western Pacific area (east coast) and the Indian Ocean area (west coast). 

Here, assessment of stock status of Ruby Snappers is presented at the biological stock level—Northern Australia (Western Australia, Northern Territory); and Eastern Australia (Queensland, New South Wales).

Northern Australia

The assessment of the stock status of Ruby Snapper in Northern Australia is based on an assessment of the relative contributions of catch from each jurisdiction and a formal assessment of the level of fishing mortality of Etelis sp. in Western Australia. The Ruby Snapper complex comprises two species, E. carbunculus (pygmy ruby snapper) and Etelis sp. (giant ruby snapper) [Wakefield et al. 2014]. These two cryptic species are sympatric and typically co-occur in catches throughout their distribution. The main species landed in northern Australian waters is Etelis sp. (currently undescribed).  

The total commercial catch of Ruby Snappers in Western Australian demersal fisheries has been variable over the last 10 years (2010–2019), ranging from 4–77 tonnes (t), with a mean annual catch of 27 t [Newman et al. 2020]. The Commonwealth catch in the Western Deepwater Trawl Fishery, operating off the West Australian Coast has been variable over the last decade (2010-2019), ranging from 0 to 28 t (28 t 2017-18; 21 t in 2018-19). Commercial harvest of Ruby Snapper in the eastern Gulf of Carpentaria is managed as part of the ‘other species’ quota category in the GOCDFFTF (inactive since 2016), which comprises other reef finfish species. Ruby Snapper is also commercially harvested by the GOCLF where there are no caps on total catch at the species or complex level. Catch has not been recorded in either Queensland fishery since 2008, when a total of 8.3 t was recorded. 

The stock assessment for Giant Ruby Snapper (Etelis sp.) in the North Western Australia region of Northern Australia is based on an assessment of fishing mortality derived from catch curve analysis of representative samples of the age structure [Wakefield et al 2020]. Point estimates of fishing mortality (F = 0.038 [1997] and 0.052 year^-1 [2011]) and associated confidence limits were well below the value for natural mortality (M) of 0.11 year^-1, indicating that, on average over the life span of the fish in the samples, exploitation has been relatively low. Estimates of mortality and selectivity from 1997 and 2011, and analyses of the female relative spawning potential ratio suggest the Etelis sp. stock in North Western Australia region has remained at around 60% of the unfished level over the years represented by the age composition sample [Wakefield et al 2020].  Given that this species is longer lived than E. carbunculus [see Williams et al 2017] and is more dominant in catches, the status of this species is considered to represent the status of Ruby Snappers in the Northern Australia stock. Catches across the distributional range of Etelis sp. are low. The above evidence indicates that the biomass of Ruby Snappers is unlikely to be depleted, recruitment is unlikely to be impaired, and the current level of fishing mortality is unlikely to cause the stock of Ruby Snappers to become recruitment impaired. 

On the basis of the evidence provided above, the Ruby Snappers species group in North Western Australia region of Northern Australia is classified as a sustainable stock.

Ruby Snappers biology [Wakefield et al. 2020]

Distribution of reported commercial catch of Ruby Snappers

Western Australia – Recreational (Catch) Boat-based recreational catch is from 1 September 2017–31 August 2018. These data are derived from those reported in Ryan et al. 2019.

Western Australia – Recreational (management methods) A Recreational Fishing from Boat Licence is required for the use of a powered boat to fish or to transport catch or fishing gear to or from a land-based fishing location.

Western Australia – Indigenous (management methods) Subject to application of Section 211 of the Native Title Act 1993 (Cth), and the exemption from a requirement to hold a recreational fishing licence, the non-commercial take by Indigenous fishers is covered by the same arrangements as that for recreational fishing.

New South Wales – Recreational (Catch) Murphy et al. [2020].

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

Queensland – Indigenous (management methods) for more information see https://www.daf.qld.gov.au/business-priorities/fisheries/traditional-fishing

Commercial catch of Ruby Snappers - note confidential catch not shown

1. Andrews, K.R., Copus, J.M., Wilcox, C., Williams, A.J., Newman, S.J., Wakefield, C.B. and Bowen, B.W. 2020. Range-wide population structure of three deepwater Eteline snappers across the Indo-Pacific basin. Journal of Heredity
2. Andrews, K.R., Williams, A.J., Fernandez-Silva, I., Newman, S.J., Copus, J.M., Wakefield, C.B., Randall, J.E., and Bowen, B.W. 2016. Phylogeny of deepwater snappers (Genus Etelis) reveals a cryptic species pair in the Indo-Pacific and Pleistocene invasion of the Atlantic. Molecular Phylogenetics and Evolution 100: 361-371.
3. Murphy, J.J., Ochwada-Doyle, F.A., West, L.D., Stark, K.E. and Hughes, J.M., 2020. The NSW Recreational Fisheries Monitoring Program - survey of recreational fishing, 2017/18. NSW DPI - Fisheries Final Report Series No. 158.
4. Newman, SJ, Wakefield, C, Skepper, C, Boddington, and Blay, N 2020, North Coast Demersal Resource Status Report 2019. pp. 159–168. In: Gaughan, D.J. and Santoro, K. (eds.). 2020. Status Reports of the Fisheries and Aquatic Resources of Western Australia 2018/19: The State of the Fisheries. Department of Primary Industries and Regional Development, Western Australia, Perth, Australia. 291p.
5. Queensland Department of Agriculture and Fisheries (2020) Reef line fishery harvest strategy: 2020–2025. Brisbane, Queensland.
6. Ryan, KL, Hall, NG, Lai, EK, Smallwood, CB, Tate, A, Taylor, SM, Wise, BS 2019, Statewide survey of boat-based recreational fishing in Western Australia 2017/18. Fisheries Research Report No. 297. Department of Primary Industries and Regional Development, Government of Western Australia, Perth.
7. Wakefield, CB, Williams, AJ, Fisher, EA, Hall, NG, Hesp, SA, Halafihi, T, Kaltavara, J, Vourey, E, Taylor, BM, O'Malley, JM, Nicol, SJ, Wise, BS, Newman, SJ 2020, Variations in life history characteristics of the deep-water giant ruby snapper (Etelis sp.) between the Indian and Pacific Oceans and application of a data-poor assessment, Fisheries Research 230 (105651)
8. Wakefield, CB, Williams, AJ, Newman, SJ, Bunel M, Dowling, CE, Armstrong, CA, and Langlois TJ, 2014, rapid and reliable multivariate discrimination for two cryptic Eteline snappers using otolith morphometry, Fisheries Research 151: 100–106
9. Williams, A.J., Wakefield, C.B., Newman, S.J., Vourey, E., Abascal, F.J., Halafihi, T., Kaltavara, J. and Nicol, S.J. 2017. Oceanic, latitudinal, and sex-specific variation in demography of a tropical deepwater snapper across the Indo-Pacific region. Front Mar Sci. 4: 382.