Hot Topic

A drop in the ocean: marine fish releases in Australia

Thursday, 1 January 1970  | 

Release of fish bred in aquaculture into the ocean to enhance marine fisheries has expanded rapidly over the last 20 years, driven by declining fish stocks in Asia and increasing recreational fishing pressure in western countries. Significant advances in release programs include a solid conceptual foundation, guiding principles to minimise environmental impacts and to maximise fisheries outcomes. Major ecological questions that determine the appropriateness of releases include: Is the population recruitment limited? Will the scale of release exceed the environmental carrying capacity? Will the release have negative impacts (e.g., disease) on the wild population or ecosystem?

In a global context, the scale of releases in Australia is small (millions of released individuals each year), especially compared with those in China and Japan (billions released). Australian releases focus on small-scale, highly-targeted releases in direct response to recruitment limitation. Programs for the Eastern King Prawn and Western School Prawn both tested prawns for disease before release. Additionally, these programs have determined the best release sites, times and densities to reduce the chance of negative effects of high-density releases, such as slower growth and higher predation rates (“more fish in = less out”). Results from the Eastern King Prawn program and those from a program for Black Bream in the Blackwood River Estuary show that the released prawns and fish contributed significantly to fisheries stocks and that the Black Bream also contributed to the spawning population.

These release programs, which were informed by ecological research and quantitative modelling, have demonstrated that “more fish in can mean more fish out” and highlight the value of monitoring, evaluating, and adaptively managing releases to maximise their potential benefits. Management policies in Western Australia and New South Wales, combined with Environmental Impact Assessment such as that required in NSW, provide a mechanism for fostering responsible release programs.

Supporting Research

Title
Aims
Sloychuk, J. R., D. P. Chivers, and M. C. O. Ferrari. 2016. Juvenile lake Sturgeon go to school: life-skills training for hatchery fish. Transactions of the American Fisheries Society 145:287-294.
Characterize the antipredator response of hatchery-reared, predator-naive young-of-the-year Lake Sturgeon Acipenser fulvescens (an endangered species) to alarm cues from injured conspecifics and test whether these alarm cues could be used to train sturgeon to recognize unknown predators.
Taylor M. D., Chick R. C., Lorenzen K., Agnalt A.-L., Leber K. M., Blankenship H. L., Haegen G. V. & Loneragan N. R. (2017) Fisheries enhancement and restoration in a changing world. Fisheries Research 186, Part 2, 407-12.
Summerise recent developments in aquaculture techniques, tagging, genetics, modelling and ecology in the context of aquaculture-based enhancement and, particularly of marine recreational fisheries
Tringali, M.D. 2006. Bayesian approach for the genetic tracking of cultured and released individuals. Fisheries Research 77: 159-172.
Develop a Bayesian framework for a parentage-based method of tracking individuals produced in captivity and released into wild populations wherein probabilities of correctly assigning parentage can be computed directly for each tested individual. Apply the method to the post-release monitoring of hatchery-reared Red Drum (Sciaenops ocellatus) in Florida.
Wang Q., Zhuang Z., Deng J. & Ye Y. (2006) Stock enhancement and translocation of the shrimp Penaeus chinensis in China. Fisheries Research 80, 67-79.
Review the biology, fishery and current status and success of stock enhancement and translocation of the Chinese White Shrimp (Penaeus chinensis) in China.
Ye Y., Loneragan N., Die D., Watson R. & Harch B. (2005) Bioeconomic modelling and risk assessment of tiger prawn (Penaeus esculentus) stock enhancement in Exmouth Gulf, Australia. Fisheries Research 73, 231-49.
Develop a bioeconomic model and risk assessment to estimate the investment and number of prawns required to increase the commercial catch of Brown Tiger Prawns (Penaeus esculentus) in Exmouth Gulf by 100 metric tonnes (i.e. a 25% increase in average annual catch)
Cottingham A., Hall N. G. & Potter I. C. (2015) Performance and contribution to commercial catches and egg production by restocked Acanthopagrus butcheri (Sparidae) in an estuary. Estuarine, Coastal and Shelf Science 164: 194-203.
Compare the growth of restocked and wild stock A. butcheri in the Blackwood Estuary. Determine whether the relationship between the lengths and ages at maturity of restocked fish differed from those of the wild stock. Elucidate the contribution restocked fish made to commercial catches. Ascertain whether restocked fish could have made a major contribution to total egg production.
Grant W. S., Jasper J., Bekkevold D. & Adkison M. (2017) Responsible genetic approach to stock restoration, sea ranching and stock enhancement of marine fishes and invertebrates. Reviews in Fish Biology and Fisheries 27: 615-49.
Use research and principles in conservation biology, resource management, fisheries science and population genetics to assemble genetic guidelines to promote a responsible genetic approach to aquaculture-based enhancements, i.e. sea ranching, restocking and stock enhancement.
Andersen K. H., Jacobsen N. S., Jansen T. & Beyer J. E. (2017) When in life does density dependence occur in fish populations? Fish and Fisheries 18, 656-67.
Review and interpret observations of density-dependence in fish populations at different life stages
Bell J. D., Watson R. A. & Ye Y. (2017) Global fishing capacity and fishing effort from 1950 to 2012. Fish and Fisheries 18, 489-505.
Estimate global fishing capacity and effort in major fishing regions from 1950 to 2012
Bell J. D., Leber K. M., Blankenship H. L., Loneragan N. R. & Masuda R. (2008) A new era for restocking, stock enhancement and sea ranching of coastal fisheries resources. Reviews in Fisheries Science 16, 1-9.
Review recent advances in restocking, stock enhancement and sea ranching programs
Bell, J.D., P.C. Rothlisberg, J.L. Munro, N.R. Loneragan, W.J. Nash, R.D. Ward, and N.L. Andrew. 2005. Restocking and stock enhancement of marine invertebrate fisheries. Advances in Marine Biology 49: 1-353.
Evaluate the status of restocking and stock enhancement initiatives for 11 major groups/species of marine invertebrates
Blankenship H. L. & Leber K. M. (1995) A responsible approach to marine stock enhancement. American Fisheries Society Symposium 15, 167-75.
Develop a responsible approach to aquaculture-based enhancement to maximise success, avoid repeating mistakes and reduce impacts on the wild population and environment.
Blount C., O’Donnell P., Reeds K., Taylor M. D., Boyd S., Van derWalt B., McPhee D. P. & Lincoln Smith M. (2017) Tools and criteria for ensuring estuarine stock enhancement programs maximise benefits and minimise impacts. Fisheries Research 186, 413-25.
Develop a suite of tools and criteria, to be used in an Environmental Impact Statement, to tailor the stock enhancement program so that it maximises benefits and minimises impacts
Broadley A. D., Tweedley J. R. & Loneragan N. R. (2017) Estimating biological parameters for penaeid restocking in a temperate Australian estuary. Fisheries Research 186, 488-501
Determine the biological parameters for growth, mortality and size at maturity of an estuarine resident prawn species to evaluate optimal release times of hatchery-reared individuals
Camp E. V., Larkin S. L., Ahrens R. N. M. & Lorenzen K. (2017) Trade-offs between socioeconomic and conservation management objectives in stock enhancement of marine recreational fisheries. Fisheries Research 186, 446-59.
Create an integrated bio-economic model to explore the nature of tradeoffs between conservation of fisheries resources and their use for socioeconomic benefit, as realized through the stock enhancement of recreational fisheries.
Chenoweth E. M., Straley J. M., McPhee M. V., Atkinson S. & Reifenstuhl S. (2017) Humpback whales feed on hatchery-released juvenile salmon. Royal Society Open Science 4.
Describe the frequency of observing humpback whales and examine the role of temporal and spatial variables affecting the probability of sighting humpback whales and describe prey capture behaviours at five hatchery release sites
Doherty, P.J. 1999. Recruitment limitation is the theoretical basis for stock enhancement in marine populations. In Stock Enhancement and Sea Ranching, ed. B.R. Howell, E. Moksness and T. Svåsand, 9-21. Oxford: Fishing News Books.
Reviews coral reef research and monitoring over decadal scales to highlight factors contributing to recruitment limitation, and opportunities this creates for aquaculture-based enhancements in these systems.
Hamasaki, K., Kitada, S. (2008). Potential of stock enhancement for decapod crustaceans. Reviews in Fisheries Science,16:1,164- 174.
Summarize the life cycle, fishery,and stocking programs for four species, i.e. the penaeid prawns Penaeus japonicus and Penaeus chinensis in Japan and China, respectively, the European lobster Homarus gammarus in Norway and the mud crab Scylla paramamosain in Japan and compare their recapture rates, the yield from the released individuals and economic efficiency of the stocking
Hilborn, R. 1998. The economic performance of marine stock enhancement projects. Bulletin of Marine Science 62: 661-674.
Review the performance of nine marine enhancement programs, to evaluate the success of existing programs, and to determine whether the benefits outweigh the costs
Hindar K., Ryman N. & Utter F. (1991) Genetic Effects of Cultured Fish on Natural Fish Populations. Canadian Journal of Fisheries and Aquatic Sciences 48, 945-57.
Review the genetic effects that have occurred following releases of hatchery-reared fish into natural environments
Hixon, M. A., and M. H. Carr. 1997. Synergistic predation, density dependence, and population regulation in marine fish. Science 277:946-949.
To prove in a controlled experiment whether spatial density-dependence occurrs in coral reef fish and determine the influence of predation.
Kitada S. & Kishino H. (2006) Lessons learned from Japanese marine finfish stock enhancement programmes. Fisheries Research 80, 101-12.
Examine the efficacy of four marine stock enhancements of two coastal finfish species in Japan to establish whether hatchery releases augmented total production without replacement of wild fish.
Kitada S., Shishidou H., Sugaya T., Kitakado T., Hamasaki K. & Kishino H. (2009) Genetic effects of long-term stock enhancement programs. Aquaculture 290, 69-79.
Investigate the genetic effects of hatchery fish on wild populations using a comparative analysis of the stocking programs for Red Sea Bream (Pagrus major) and Pacific Herring (Clupea pallasii) in Japan.
Leber K. M. & Arce S. M. (1996) Stock enhancement in a commercial mullet, Mugil cephalus L., fishery in Hawaii. Fisheries Management and Ecology 3, 261-78.
Determine the contribution hatchery-reared Sea Mullet (Mugil cephalus) made to a commercial fishery in Hawaii
Loneragan, N.R., G.I. Jenkins, and M.D. Taylor. 2013. Marine stock enhancement, restocking, and sea ranching in Australia: Future directions and a synthesis of two decades of research and development. Reviews in Fisheries Science 21: 222-236.
Synthesize information on marine and estuarine release programs in Australia and evaluate potential future opportunities for stock enhancement.
Lorenzen K. (2005) Population dynamics and potential of fisheries stock enhancement: practical theory for assessment and policy analysis. Philosophical Transactions of the Royal Society B: Biological Sciences 360, 171.
To review knowledge of fish population biology and extend the dynamic pool theory of fishing to stock enhancement by unpacking recruitment, incorporating regulation in the recruited stock, and
Lorenzen K. (2014) Understanding and managing enhancements: why fisheries scientists should care. Journal of Fish Biology 85, 1807-29.
Provide 10 reasons why fisheries scientists should care about understanding and managing fishery enhancements
Lorenzen K., Agnalt A.-L., Blankenship H. L., Hines A. H., Leber K. M., Loneragan N. R. & Taylor M. D. (2013) Evolving context and maturing science: aquaculture-based enhancement and restoration enter the marine fisheries management toolbox. Reviews in Fisheries Science 21, 213-21.
To review developments in aquaculture, fisheries, and coastal ecology that provide important context for the future potential of aquaculture-based enhancement and restoration. Highlight key developments in the science base of enhancements and recent policy developments.
Lorenzen K. & Enberg K. (2002) Density-Dependent Growth as a Key Mechanism in the Regulation of Fish Populations: Evidence from among-Population Comparisons. Proceedings: Biological Sciences 269, 49-54.
Determine whether density-dependent growth in the recruited phase is a ey process in the regulation of fish populations
Lorenzen, K., K.M. Leber, and H.L. Blankenship. 2010. Responsible approach to marine stock enhancement: An update. Reviews in Fisheries Science 18: 189-210.
Update the set of principles aimed at promoting responsible development of restocking, stock enhancement, and sea ranching proposed by Blankenship and Leber (1995), which has gained widespread acceptance as the ‘Responsible Approach’.
Pile A. J., Lipcius R. N., van Montfrans J. & Orth R. J. (1996) Density-Dependent Settler-Recruit-Juvenile Relationships in Blue Crabs. Ecological Monographs 66, 277-300.
Determine the settler-recruit relationship of Blue Crabs (Callinectes sapidus) using 10 years of abundance data from nursery habitats and identify potential density-dependent mechanisms governing the loss of crabs in nursery habitats.
Svåsand T., Kristiansen T. S., Pedersen T., Salvanes A. G. V., Engelsen R., Nævdal G. & Nødtvedt M. (2000) The enhancement of cod stocks. Fish and Fisheries 1, 173-205.
Review the major findings from stock enhancement programs for Atlantic Cod (Gadus morhua), including evaluations of hatchery techniques, tagging and recapture methods, fishing techniques and the biologial characteristcs of species in different habitats.
Sloychuk, J. R., D. P. Chivers, and M. C. O. Ferrari. 2016. Juvenile lake Sturgeon go to school: life-skills training for hatchery fish. Transactions of the American Fisheries Society 145:287-294.
Characterize the antipredator response of hatchery-reared, predator-naive young-of-the-year Lake Sturgeon Acipenser fulvescens (an endangered species) to alarm cues from injured conspecifics and test whether these alarm cues could be used to train sturgeon to recognize unknown predators.
Taylor M. D., Chick R. C., Lorenzen K., Agnalt A.-L., Leber K. M., Blankenship H. L., Haegen G. V. & Loneragan N. R. (2017) Fisheries enhancement and restoration in a changing world. Fisheries Research 186, Part 2, 407-12.
Summerise recent developments in aquaculture techniques, tagging, genetics, modelling and ecology in the context of aquaculture-based enhancement and, particularly of marine recreational fisheries
Tringali, M.D. 2006. Bayesian approach for the genetic tracking of cultured and released individuals. Fisheries Research 77: 159-172.
Develop a Bayesian framework for a parentage-based method of tracking individuals produced in captivity and released into wild populations wherein probabilities of correctly assigning parentage can be computed directly for each tested individual. Apply the method to the post-release monitoring of hatchery-reared Red Drum (Sciaenops ocellatus) in Florida.
Wang Q., Zhuang Z., Deng J. & Ye Y. (2006) Stock enhancement and translocation of the shrimp Penaeus chinensis in China. Fisheries Research 80, 67-79.
Review the biology, fishery and current status and success of stock enhancement and translocation of the Chinese White Shrimp (Penaeus chinensis) in China.
Ye Y., Loneragan N., Die D., Watson R. & Harch B. (2005) Bioeconomic modelling and risk assessment of tiger prawn (Penaeus esculentus) stock enhancement in Exmouth Gulf, Australia. Fisheries Research 73, 231-49.
Develop a bioeconomic model and risk assessment to estimate the investment and number of prawns required to increase the commercial catch of Brown Tiger Prawns (Penaeus esculentus) in Exmouth Gulf by 100 metric tonnes (i.e. a 25% increase in average annual catch)
Cottingham A., Hall N. G. & Potter I. C. (2015) Performance and contribution to commercial catches and egg production by restocked Acanthopagrus butcheri (Sparidae) in an estuary. Estuarine, Coastal and Shelf Science 164: 194-203.
Compare the growth of restocked and wild stock A. butcheri in the Blackwood Estuary. Determine whether the relationship between the lengths and ages at maturity of restocked fish differed from those of the wild stock. Elucidate the contribution restocked fish made to commercial catches. Ascertain whether restocked fish could have made a major contribution to total egg production.
Grant W. S., Jasper J., Bekkevold D. & Adkison M. (2017) Responsible genetic approach to stock restoration, sea ranching and stock enhancement of marine fishes and invertebrates. Reviews in Fish Biology and Fisheries 27: 615-49.
Use research and principles in conservation biology, resource management, fisheries science and population genetics to assemble genetic guidelines to promote a responsible genetic approach to aquaculture-based enhancements, i.e. sea ranching, restocking and stock enhancement.