Western Blue Groper, Achoerodus gouldii (Richardson 1843)
A male Western Blue Groper, Achoerodus gouldii, at Esperance, Western Australia, March 1978. Source: @leucopogon / iNaturalist.org. License: CC By Attribution-NonCommercial
These large inquisitive wrasses are hermaphrodites and may change sex from female to male during their life cycle. Juveniles are greenish with scattered pale spots. Adult females are typically greyish-green to reddish in colour, and the males are greyish to bright blue.
Western Blue Groper inhabit exposed rocky reefs in coastal waters of southern and south-western Australia. They have a single long-based dorsal fin, a large squarish tail, thick fleshy lips, large heavy scales and peg-like teeth.
Video of a male Western Blue Groper on Lonsdale Wall, just inside the heads of Port Philip,Victoria.
Video of a female Western Blue Groper (and a Horseshoe Leatherjacket) in South Australia.
Western Blue Groper, Achoerodus gouldii (Richardson 1843)
More Info
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Distribution |
Western Blue Groper are endemic to temperate coastal waters of southern Australia, from about Inverloch, Victoria, west to Geraldton and the Houtman Abrolhos, Western Australia. The species is most abundant on reefs (above 60 m) in South Australia and southern Western Australia. Although reportedly common on the southern coasts of the Fleurieu and Yorke peninsulas during the 1960's, Western Blue Groper are now uncommon around in these areas, as well as in the upper waters of Spencer Gulf. They are also rare in the Perth area. The species is reportedly also rare east of the Murray River mouth, although Western Blue Groper are now often seen by divers outside Port Phillip Heads, Victoria, and more recently within Port Phillip. Western Blue Groper are also reportedly rare north of Perth, Western Australia. Adults inhabit coastal and offshore reefs reefs in depths to 100 m, usually at depths of 5 to about 40 m. Juveniles prefer relatively sheltered waters, such as shallow inshore macroalgal-covered reefs and seagrass meadows. As they mature, they usually move to deeper offshore reefs. |
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Features |
Dorsal fin XI, 11; Anal fin III, 11; Pectoral fin 16-18; Pelvic fin I, 5; Caudal fin 14; Lateral line scales 33-37; Scales above Llat 7-7.5. Body moderately long and deep, depth 32-41 % SL; hump on forehead in large adults; mouth moderately small, not reaching eye; lips very fleshy, hood-like; each jaw with 2 pairs of flattened canines at the front, lateral teeth mostly embedded and fused with jaw, usually no enlarged canine at rear of upper jaw. Scales moderately large, covering rear of head including cheeks, onto bases of dorsal and anal fins; lateral line smoothly curved; caudal fin truncate with rounded corners; ventral fin short, distinctly not reaching anus. |
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Size |
To a maximum length of 1.75m TL, and a weight of up to 40kg. |
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Colour |
Juveniles are greenish, sometimes with yellowish or whitish spots scattered over the back. Females are greyish to red, and males are greyish to blue. |
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Feeding |
Feed on benthic invertebrates such as crabs, sea urchins and molluscs, including abalone. They use their strong peg-like teeth to prise urchins and molluscs off rocks, and will also bite off pieces of algal mat, consuming small crustaceans and other benthic invertebrates that live amongst the algae. |
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Biology |
Western Blue Groper grow very slowly, take a long time to mature and are very long-lived. Individuals at 40 cm in length are about 8 years old, and those measuring 80 cm are about 25 years old. Their length does not increase much after they are 30 years old. Ageing studies that involve counting the rings on otoliths (ear bones) have shown that large males may live to 70 years of age - one of the longest life spans for a wrasse. Individuals increase little in length beyond about 30 years of age. Like most wrasses, Western Blue Groper (Achoerodus gouldii) are protogynous hermaphrodites, meaning that some individuals change sex from female to male during their life cycle. Juveniles possess both female and male reproductive tissue. They mature slowly, becoming sexually mature females (initial phase) on average at about 15-20 years of age at a length of about 65 cm. Individual females are capable of changing sex to terminal phase males at about 82 cm in length at between 30 and 35 years of age. This sex change is accompanied by a change in colour from greenish to blue. They live in small social groups or 'harems' comprised of a dominant adult male (the largest member of the group), one to two adult females, and several subadult females. If the male dies or is removed from the group (by fishing for example), the dominant female will change sex and colour over a period of about two weeks and become the dominant male. Spawning occurs in deeper offshore waters between early winter and mid-spring. Although there is no information available on larval Western Blue Groper, the larvae of Eastern Blue Groper, Achoerodus viridis, have been described Leis & Hay 2004). |
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Fisheries |
A highly regarded commercial and recreational species, and targeted in the commercial gillnet fishery on the south Western Australian coast in 20-100 m. Western Blue Groper is the second-most important scale fish on the south coast of Western Australia. Blue groper are site-attached meaning that they tend to remain in 'home range', and are vulnerable to overfishing. In the past, they have been exploited by spearfishers and anglers because of their large size and reputation as an excellent eating fish, causing numbers to decline. |
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Conservation |
IUCN Red List: VULNERABLE. Western Blue Groper are very vulnerable to heavy fishing pressure, as the species is extremely long-lived, taking many years to reach sexual maturity firstly as a female (initial phase), and even longer to be able to change sex from female to male. South Australia - protected in parts of their range. Under the South Australian Fisheries Management Act 2007, fishing for Western Blue Groper is prohibited in Spencer Gulf, Gulf St Vincent, Investigator Strait and Backstairs Passage. Victoria - totally protected. Western Australia - totally protected within the Rottnest Island Marine Reserve. Outside the Reserve, anglers have a bag limit of one Blue Groper, with a minimum size limit of 50cm. Restrictions also apply to commercial fisheries elsewhere in Western Australia. Populations along the west coast have declined and the species is rarely sighted in the Perth area. |
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Remarks |
The Western Blue Groper is the largest bony fish found along Australia's southern coast. |
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Similar Species |
Western Blue Groper are very similar to, and difficult to tell apart from Eastern Blue Groper, Achoerodus viridis. They have slightly larger scales, 33-37 pored lateral line scales, and 7-7.5 scale rows between the lateral line and the dorsal-fin origin. Eastern Blue Groper have 41-45 pored lateral line scales, and 9-10.5 scale rows between the lateral line and the dorsal-fin origin. Western Blue Groper also grow to a larger size and live longer than their eastern relatives. |
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Etymology |
The species is named for the noted Australian naturalist John Gould. |
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Species Citation |
Labrus gouldii Richardson 1843, Ann. Mag. Nat. Hist. 1 11(71): 353. Type locality: Western Australia |
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Author |
Bray, D.J. 2020 |
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Resources |
Western Blue Groper, Achoerodus gouldii (Richardson 1843)
References
Barrett, N. S. 1995. Short- and long-term movement patterns of six temperate reef fishes (Families Labridae and Monacanthidae). Marine and Freshwater Research 46: 853-860.
Brook, J. 2014. Current status of western blue groper at selected locations in South Australia: results of the 2014 survey and comparison with historical surveys. Report to the Conservation Council of South Australia. J Diversity Pty Ltd, Adelaide. 24 pp.
Bryars, S., Rogers, P., Huveneers, C., Payne, N., Smith, I. & McDonald, B. 2012. Small home range in southern Australia’s largest resident reef fish, the western blue groper (Achoerodus gouldii): implications for adequacy of no-take marine protected areas. Marine and Freshwater Research 63(6): 552-563. http://dx.doi.org/10.1071/MF12016
Choat, J.H., Gillanders, B. & Pollard, D. 2010. Achoerodus gouldii. The IUCN Red List of Threatened Species 2010: e.T187520A8556943. https://dx.doi.org/10.2305/IUCN.UK.2010-4.RLTS.T187520A8556943.en. Downloaded on 03 December 2019.
Coulson, P.G. 2008. The biology of three teleost species with divergent life cycle characteristics and their implications for fisheries management. PhD thesis, Murdoch University, Western Australia, 182 pp.
Coulson, P.G., Hesp, S.A., Hall, N.G. & Potter, I.C. 2009. The western blue groper (Achoerodus gouldii), a protogynous hermaphroditic labrid with exceptional longevity, late maturity, slow growth, and both late maturation and sex change. Fishery Bulletin 107(1): 57-75.
Coulson, P., Potter, I., Hesp, S. & Hall, N. 2007. Biological parameters required for managing Western Blue Groper, Blue Morwong and Yellowtail Flathead. FRDC Report 2004/57
DeLacy, C. 2008. Reef fish community structure and dynamics: response to human disturbance. PhD thesis, School of Plant Biology, Faculty of Natural and Agricultural Sciences, The University of Western Australia.
Edgar, G.J. 2008. Australian Marine Life: the plants and animals of temperate waters. Sydney : Reed New Holland 2nd edn, 624 pp.
Edmunds, M., Hart, S., Elias, J. & Jenkins, S. 2003. Victorian Subtidal Reef Monitoring Program: The Reef Biota at Port Phillip Heads Marine National Park. Parks Victoria Technical Series No. 5. Parks Victoria, Melbourne.
Edmunds, M., Hart, S., Elias, J. & Power, B. 2003. Victorian Subtidal Reef Monitoring Program – The Reef Biota at Bunurong Marine National Park and Surrounding Coast. Parks Victoria Technical Series No. 3. Parks Victoria, Melbourne.
Gillanders, B.M. 1999. Blue groper. pp. 188-193 In: Andrew, N.L. (ed.) Under Southern Seas. The Ecology of Australia’s Rocky Reefs. UNSW Press Ltd, Sydney. 238 pp.
Glover, J.C.M. 1987. Threatened fish species in South Australia, pp 55-58. In Harris, J.H. Proceedings of the Conference on Australian Threatened Fishes - Conducted by the Australian Society of Fish Biology. Dept. of Agriculture, Sydney. 70 pp.
Gomon, M.F. 1997. Relationships of fishes of the labrid tribe Hypsigenyini. Bulletin of Marine Science 60(3): 789-871 figs 1-39, 4 tables
Gomon, M.F. &. Russell, B.C. 1994. Family Labridae. pp. 675-699 in Gomon, M.F., Glover, C.J.M. & Kuiter, R.H. (eds). The Fishes of Australia's South Coast. Adelaide : State Printer 992 pp. 810 figs.
Hart, S.P., Edmunds, M., Ingwersen, C. & Elias, J. 2004. Victorian Subtidal Reef Monitoring Program: The reef biota on the Western Victorian Coast. Parks Victoria Technical Series No. 14. Parks Victoria, Melbourne.
Henry, G.W. & Lyle, J.M. 2003. The National Recreational and Indigenous Fishing Survey. NSW Fisheries Final Report Series: 48. Fisheries Research & Development Corporation and the Fisheries Action Program, Canberra, Australia.
Hoschke, A., Whisson, G. & Moore, G.I. 2019. Complete list of fishes from Rottnest Island. pp. 150-161 in Whisson, G. & Hoschke, A. (eds) The Rottnest Island fish book. 2nd ed. Perth : Aqua Research and Monitoring Services.
Hutchins, J.B. 1994. A survey of the nearshore reef fish fauna of Western Australia's west and south coasts — The Leeuwin Province. Records of the Western Australian Museum, Supplement46: 1-66 figs 1-6
Hutchins, J.B. 1997. Checklist of fishes of the Houtman Abrolhos Islands, Western Australia. pp. 239-253 in Wells, F. (ed.) The Marine Fauna and Flora of the Houtman Abrolhos Islands, Western Australia. Perth : Western Australian Museum.
Hutchins, J.B. 2001. Biodiversity of shallow reef fish assemblages in Western Australia using a rapid censusing technique. Records of the Western Australian Museum 20: 247-270Hutchins, J.B. & Swainston, R. 1986. Sea Fishes of Southern Australia. Complete field guide for anglers and divers. Perth : Swainston Publishing 180 pp.
Hutchins, J.B. & Thompson, M. 1983. The Marine and Estuarine Fishes of South-western Australia. Perth : Western Australian Museum 103 pp. 345 figs.Klunzinger, C.B. 1879. Die v. Müller'sche Sammlung Australischer Fische. Anzeiger der Kaiserlichen Akademie der Wissenschaften. Mathematisch-Naturwissenschaftliche Klasse, Wien 16(22): 254-261 (described as Platychoerops muelleri)
Klunzinger, C.B. 1880. Die von Müller'sche Sammlung australischer Fische in Stuttgart. Sitzungsberichte der Kaiserlichen Akademie der Wissenschaften. Mathematisch-Naturwissenschaftliche Classe 80(1. Abth.)(3-4): 325-430, Pls. 1-9. See ref at BHL
Kuiter, R.H. 1993. Coastal Fishes of South-eastern Australia. Bathurst : Crawford House Press 437 pp.
Kuiter, R.H. 1997. Guide to sea fishes of Australia. A comprehensive reference for divers and fishermen. New Holland Publishers, Frenchs Forest, NSW, Australia. 434 pp.
Kuiter, R.H. 2010. Labridae fishes: wrasses. Seaford, Victoria, Australia : Aquatic Photographics 398 pp.
Leis, J.M. & A.C. Hay. 2004. Larval development of Achoerodus viridis(Pisces; Labridae), the Australian eastern blue groper. Ichthyological Research 51: 46-51.
May, J.L. & Maxwell, J.G.H. 1986. Field Guide to Trawl Fish from Temperate Waters of Australia. Hobart : CSIRO Division of Marine Research 492 pp.
Pogonoski, J.J., Pollard, D.A. & Paxton, J.R. 2002. Conservation overview and action plan for Australian threatened and potentially threatened marine and estuarine fishes. Environment Australia, Canberra, Australia.
Richardson, J. 1843. Contributions to the ichthyology of Australia. Annals and Magazine of Natural History 1 11(71): 352-359. See ref at BHL
Rountrey, A.N., Coulson, P.G., Meeuwig, J.J. & Meekan, M. 2014, Water temperature and fish growth: otoliths predict growth patterns of a marine fish in a changing climate. Global Change Biology 20: 2450-2458. https://doi.org/10.1111/gcb.12617
Russell, B.C. & Gomon, M.F. 2008. Family Labridae. pp. 638-659 in Gomon, M.F., Bray, D.J. & Kuiter, R.H. (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp.
Shepherd, S.A. 2005. Ontogenetic changes in diet, feeding behaviour and activity of the western blue groper, Achoerodus gouldii. In Wells, F. & Kendrick, G. (eds) The Marine Flora and Fauna of Esperance, Western Australia. WA Museum, Perth, Western Australia.
Shepherd, S.A. 2005. Beautiful, friendly and susceptible Blue Groper. Southern Fisheries 12(1): 29.
Shepherd, S.A. & Brook, J.B. 2005. 2004 expedition to Althorpe Island, South Australia: foraging ecology of the Western Blue Groper, Achoerodus gouldii. Transactions of the Royal Society of South Australia 129(2): 202-208.
Shepherd, S.A. & Brook, J.B. 2005. Foraging ecology of the western Blue Groper, Achoerodus gouldii, at the Althorpe Islands, South Australia, Transactions of the Royal Society of South Australia 129(2): 202-208.
Shepherd, S.A. & Brook. J. 2007. Distribution and ontogenetic shifts in habitat and abundance of the temperate western blue groper, Achoerodus gouldii (Richardson). Journal of Fish Biology 71(5): 1457-1478.
Winton, Tim. 2008. Blueback. Penguin, Australia. 168 pp. [A novel for all ages]
Yearsley, G.K., Last, P.R. & Ward, R.D. (eds) 1999. Australian Seafood Handbook: an Identification Guide to Domestic Species. CSIRO Marine Research, Hobart. 461 pp.
