Pearl Perch (2023)
Glaucosoma scapulare
Date Published: June 2023
Summary
Pearl Perch is a demersal fish endemic to the central NSW and QLD coast of Australia. Fishing levels have exceeded sustainable levels and the stock status is depleted.
Stock Status Overview
Jurisdiction | Stock | Stock status | Indicators |
---|---|---|---|
New South Wales, Queensland | Eastern Australia | Depleted | Stock assessment, biomass, standardised catch rate, fishery-dependent length and age, catch and effort |
Stock Structure
The Pearl Perch (Glaucosoma scapulare) is a long-lived demersal species endemic to the central east coast of Australia. Pearl Perch generally form schools around submerged reefs, gravel, pinnacles and rough, rocky seabed in depths to at least 200 m [Campbell et al. 2023]. Pearl Perch have a limited distribution which extends from Rockhampton in Queensland (23°20’S) south to central New South Wales [Stewart et al. 2013]. Due to this limited distribution and influence of the prevailing southerly flowing Eastern Australian Current in distributing larvae across this area [Ridgway and Dunn 2003], Pearl Perch are considered to be a single biological stock [Stewart et al. 2015].
Here the assessment of stock status is presented at the biological stock level—Eastern Australia.
Stock Status
Eastern Australia
The most recent integrated stock assessment for the Eastern Australia Pearl Perch stock (Queensland and New South Wales combined; including data up until 2019) estimated spawning biomass had declined to 22% (base case; 14–46% range across scenarios), relative to unfished levels [Lovett et al. 2022]. This assessment produced slightly higher biomass estimates than the previous stock assessment [Sumpton et al 2017]; however, it also indicated a rapid and consistent decline in biomass from 2005. Standardised commercial catch rates in Queensland showed a declining trend between 1988 and 2019 [Lovett et al. 2022]. Standardised catch rates for Queensland are not available post 2019 to 2021–22, although nominal catch rates in the New South Wales line fishery have increased considerably since 2018–19.
Fishery-dependent monitoring in Queensland showed length frequencies in 2021 were dominated by fish within the first 15 cm above minimum legal size (380–520 mm), particularly in the recreational sector [QDAF 2023 Unpublished data]. In New South Wales, length-based monitoring of commercial landings showed a lower frequency of smaller fish (300–400 mm) in landings between 2011–12 and 2015–16, indicating poor recruitment to the fishery [Stewart 2020]. However, a pulse of just legal-sized Pearl Perch was detected in landings during 2016–17, signalling the start of a period of improved recruitment that has been observed each year to 2021–22 [Stewart 2020; NSW DPI Unpublished data]. Fishery-dependent age frequencies in Queensland waters showed no clear signs of strong recruitment throughout the monitoring period (2006– 21). Fishery-dependent monitoring in Queensland and New South Wales showed truncated commercial and recreational age frequencies with few older (10 years+) fish [Stewart 2011; Stewart et al. 2013; Stewart 2020; QDAF 2023 Unpublished data]. Although there are encouraging signals in New South Wales length monitoring data, indicating improved recruitment in recent years, there is no additional evidence to suggest the biomass of the Eastern Australia stock is recovering. The stock is therefore considered to be recruitment impaired.
Fishing mortality on the Eastern Australia stock of Pearl Perch was assessed as exceeding sustainable levels during the most recent stock assessment [Lovett et al. 2022]. Harvest reconstruction shows historical landings (between 1975 and 2010) exceeded the estimated maximum sustainable yield of 74 t from the stock [Lovett et al. 2022]. Since that time the combined harvest from Queensland and New South Wales has been at historically low levels, most recently 45 t in 2021–22. Commercial harvest from the southern component of the Queensland fishery (Fraser Offshore south) continues to decline by weight and proportion—from a peak of 70% in the last decade to 30% of the total commercial harvest in 2021–22. The commercial fishery in Queensland has expanded and shifted north, with the few older fish observed in monitoring coming from this region [QDAF 2023 Unpublished Data]. This spatial shift may be an indication that biomass has been subject to depletion in the traditional fishing grounds. In 2021–22, the Queensland charter sector harvest matched that taken by the commercial fleet. Estimates of the recreational harvest in Queensland decreased by number and increased by weight from 2013–14 (9,963 fish; estimated 11.3 t) to 2019–20 (9,048 fish; estimated 14.3 t) and catch rates increased over the same period [Webley et al. 2015; Teixeira et al. 2021]. In NSW recreational harvest estimates for Pearl Perch are not robust (i.e. low sample sizes and large standard errors) but may be around 9,000 fish per year [Murphy et al. 2020; Murphy et al. 2022].
In Queensland, active commercial fishing licences and fishing effort days in 2021–22 further reduced from the 2019 stock assessment and effort halved compared to the previous 10-year average. Fishing effort days in the Queensland charter sector also reduced by 25% from the previous 10-year average. In New South Wales the number of days reported when Pearl Perch were landed in both trap and line fisheries were at historically low levels [Stewart 2020; NSW DPI Unpublished data]. In Queensland, from September 2019, attempts to reduce fishing mortality were introduced through an increased minimum legal size from 350 to 380 mm, a reduced recreational possession limit from five to four, a total allowable commercial catch limit established at 15 tonnes and a one month seasonal closure in July–August introduced. There is a minimum legal length of 300 mm total length and a recreational bag limit of five fish for Pearl Perch in New South Wales.
Despite changes to management arrangements to alleviate fishing mortality, evidence from the most recent stock assessment [Lovett et al. 2022] and relevant Management Strategy Evaluation [Campbell et al. 2021] suggest fishing mortality has not been reduced enough to support stock recovery . The current level of fishing mortality is expected to prevent the stock from recovering from its recruitment impaired state.
On the basis of the evidence provided above, the Eastern Australia biological stock is classified as a depleted stock.
Biology
Pearl Perch biology [McKay 1997, Sumpton et al. 2013, Campbell et al. 2022, Campbell et al. 2023]
Species | Longevity / Maximum Size | Maturity (50 per cent) |
---|---|---|
Pearl Perch | 27 years, 700 mm TL, 7.3 kg |
Females 4.42 years, 373 mm TL |
Tables
Queensland | New South Wales | |
---|---|---|
Commercial | ||
Line | ||
Hook and Line | ||
Demersal Longline | ||
Dropline | ||
Various | ||
Fish Trap | ||
Charter | ||
Line | ||
Hook and Line | ||
Recreational | ||
Line | ||
Spearfishing | ||
Hook and Line | ||
Indigenous | ||
Various | ||
Spearfishing | ||
Hook and Line |
Method | Queensland | New South Wales |
---|---|---|
Charter | ||
Bag and possession limits | ||
Bag limits | ||
Gear restrictions | ||
Licence | ||
Marine park closures | ||
Possession limit | ||
Processing restrictions | ||
Seasonal or spatial closures | ||
Size limit | ||
Spatial closures | ||
Commercial | ||
Gear restrictions | ||
Limited entry | ||
Marine park closures | ||
Processing restrictions | ||
Seasonal or spatial closures | ||
Size limit | ||
Spatial closures | ||
Total allowable catch | ||
Vessel restrictions | ||
Indigenous | ||
Customary fishing management arrangements | ||
Recreational | ||
Bag and possession limits | ||
Bag limits | ||
Gear restrictions | ||
Licence | ||
Marine park closures | ||
Possession limit | ||
Processing restrictions | ||
Seasonal or spatial closures | ||
Size limit | ||
Spatial closures |
Queensland | New South Wales | |
---|---|---|
Commercial | 8.53t | 6.14t |
Indigenous | Unknown | Unknown |
Recreational | 15.7 t in 2013–14, 14.3 t in 2019–20 | 7,508 fish retained in 2019–20 |
Queensland – Indigenous (Management Methods). For more information see https://www.daf.qld.gov.au/business-priorities/fisheries/traditional-fishing
Queensland – Recreational (Catch). Data are based at the whole of Queensland level and derived from statewide recreational fishing surveys. Where possible, estimates have been converted to weight (tonnes) using best known conversion multipliers. Conversion factors may display regional or temporal variability. In the absence of an adequate conversion factor, data presented as number of fish.
Queensland – Commercial and Charter (Catch). Queensland commercial and charter data have been sourced from the commercial fisheries logbook program. Further information is available through the Queensland Fisheries Summary Report https://www.daf.qld.gov.au/business-priorities/fisheries/monitoring-research/data/queensland-fisheries-summary-report
Queensland – Commercial (Management Methods). Harvest strategies are available at: https://www.daf.qld.gov.au/business-priorities/fisheries/sustainable/harvest-strategy
New South Wales – Recreational (Catch). Murphy et al. [2020] and Murphy et al. [2022]
New South Wales – Indigenous (Management Methods). https://www.dpi.nsw.gov.au/fishing/aboriginal-fishing
References
- Campbell, MJ, Joiner, JE, McLennan, MF and Tibbetts, IR 2023, Sea Surface Temperature Affects the Reproductive Biology of Female Pearl Perch (Glaucosoma scapulare Macleay, 1881) in Queensland, Australia Journal of Applied Ichthyology Volume 2023, p. 5529782. ISSN 0175-8659
- Campbell, MJ, McLennan, MF, Nicolson, JR, Garland, A, Prosser, RM and Midgley, RF 2022, Improving estimates of growth for pearl perch (Glaucosoma scapulare) in Queensland, Australia Aquaculture, Fish and Fisheries, vol. 3, no. 1, pp. 71–80, 2022.
- Campbell, MJ, O’Neill, MF, Taggart, K, Khorsandian, A, Kruek, N, Dijkstra, B, Brady, P and Hussain, S 2021, Development of a user-friendly MSE framework for Queensland’s rocky reef fishery, Department of Agriculture and Fisheries, Brisbane, Queensland.
- Fisheries Queensland 2017, Queensland Sustainable Fisheries Strategy 2017–2027. Department of Agriculture and Fisheries, Brisbane, Australia.
- Lovett, R, Northtrop, A and Stewart, J 2022, Stock assessment of Australian pearl perch (Glaucosoma scapulare) with data to December 2019, Department of Agriculture and Fisheries, Brisbane.
- McKay, RJ, 1997, FAO Species Catalogue, Vol. 17, Pearl perches of the world (family Glaucosomatidae). An annotated and illustrated catalogue of the pearl perches known to date, FAO Fisheries Synopsis, 125(17): 26p. Rome: FAO.
- Murphy, JJ, Ochwada-Doyle, FA, West, LD, Stark, KE and Hughes, JM 2020, The NSW Recreational Fisheries Monitoring Program - survey of recreational fishing, 2017/18. NSW DPI - Fisheries Final Report Series No. 158.
- Murphy, JJ, Ochwada-Doyle, FA, West, LD, Stark, KE, Hughes, JM, and Taylor, MD 2022, Survey of recreational fishing in NSW, 2019/20 – Key Results. NSW DPI – Fisheries Final Report Series No. 161. ISSN 2204-8669.
- Queensland Department of Agriculture and Fisheries, Unpublished Data, Fishery Monitoring Database (QFSFRM). Viewed 13 August 2023. Brisbane, Queensland.
- Ridgway, KR and Dunn, JR 2003, Mesoscale structure of the mean East Australian Current System and its relationship with topography, Progress in Oceanography, vol. 56 pp. 189–222
- Stewart, J 2011, Evidence of age-class truncation in some exploited marine fish populations in New South Wales, Australia. Fisheries Research, 108 (1): 209–213.
- Stewart, J 2020, NSW Stock Status Summary 2018/19 – Pearl Perch – (Glaucosoma scapulare). NSW Department of Primary Industries. Fisheries NSW. 10 pp.
- Stewart, J, Hegarty, A, Young, C, Fowler, AM and Craig, J 2015, Status of fisheries resources in NSW 2013–14, NSW Department of Primary Industries, Mosman, 391 pp.
- Stewart, J, Sumpton, W, Lockett, M and Hughes, JM 2013, Age‐based demographics of the pearl perch Glaucosoma scapulare (Ramsay, 1881), Journal of Applied Ichthyology, 29(4), 801–807.
- Sumpton, W, O’Neill, MF, Campbell, M, McLennan, M and Campbell, AB 2017, Stock assessment of the Queensland and New South Wales pearl perch (Glaucosoma scapulare) fishery, Department of Agriculture and Fisheries, Brisbane.
- Teixeira, D, Janes, R, and Webley, J 2021, 2019–20 Statewide Recreational Fishing Survey Key Results. Project Report. State of Queensland, Brisbane.
- Webley, J, McInnes, K, Teixeira, D, Lawson, A and Quinn, R 2015, Statewide Recreational Fishing Survey 2013–14, Department of Agriculture and Fisheries, Queensland.