Many freshwater fishes are imperilled globally, and there is a need for easily accessible, contemporary ecological knowledge to guide management. This compendium contains knowledge collated from over 600 publications and 27 expert workshops to support the restoration of 9 priority native freshwater fish species, representative of the range of life-history strategies and values in south-eastern Australia’s Murray–Darling Basin. To help prioritise future research investment and restoration actions, ecological knowledge and threats were assessed for each species and life stage. There is considerable new knowledge (80% of publications used were from the past 20 years), but this varied among species and life stages, with most known about adults, then egg, juvenile and larval stages (in that order). The biggest knowledge gaps concerned early life stage requirements, survival, recruitment, growth rates, condition and movements. Key threats include reduced longitudinal and lateral connectivity, altered flows, loss of refugia, reductions in both flowing (lotic) and slackwater riverine habitats, degradation of wetland habitats, alien species interactions and loss of aquatic vegetation. Examples and case studies illustrating the application of this knowledge to underpin effective restoration management are provided. This extensive ecological evidence base for multiple species is presented in a tabular format to assist a range of readers.

Stock enhancement is a management tool used for fishery recovery worldwide, yet the success of many stocking programs remains unquantified. Murray cod (Maccullochella peelii) and golden perch (Macquaria ambigua) are important Australian recreational target species that have experienced widespread decline. Stocking of these species has been undertaken for decades, with limited assessment of effectiveness. A batch marking and recapture approach was applied to assess stocked Murray cod and golden perch survival, contributions to wild fisheries, and condition in rivers and impoundments. Stocked fish were marked with calcein. Marked fish were detected during surveys undertaken 3 years and 10 months from initial marking, and it is probable that marks will persist beyond this time. The proportion of calcein marked fish in the population sub-sample whose age was equal to, or less than, the number of years since release, varied by 7–94% for Murray cod, and 9–98% for golden perch. Higher proportions of marked fish were found in impoundments than rivers. Marked Murray cod had significantly steeper length–weight relationships (i.e. higher weight at a given length) to unmarked fish. Our results show that application of methods for discriminating stocked and wild fish provides critical information for the development of adaptive, location-specific stocking strategies.

Localized catastrophic events can dramatically affect fish populations. Management interventions, such as stocking, are often undertaken to re-establish populations that have experienced such events. Evaluations of the effectiveness of these interventions are required to inform future management actions. Multiple hypoxic blackwater events in 2010-2011 substantially reduced fish communities in the Edward-Wakool river system in the southern Murray-Darling Basin, New South Wales, Australia. These events led to extensive fish kills across large sections of the entire system following a period of prolonged drought. To expedite recovery efforts, 119 661 golden perch Macquaria ambigua and 59 088 Murray cod Maccullochella peelii fingerlings were stocked at five locations over 3 years. All fish stocked were chemically marked with calcein to enable retrospective evaluation of wild or hatchery origin. Targeted collections were undertaken 3 years post-stocking to investigate the relative contribution of stocking efforts and recovery via natural recruitment in the system. Of the golden perch retained for annual ageing (n = 93) only nine were of an age that could have coincided with stocking activities. Of those, six were stocked. The dominant year-class of golden perch were spawned in 2009; before the stocking programme began and prior to blackwater events. All Murray cod retained (n = 136) were of an age that coincided with stocking activities, although only eight were stocked. Among the Murray cod captured, the dominant year-class was spawned in 2011, after the blackwater events occurred. The results from this study provide first evidence that natural spawning and recruitment, and possibly immigration, were the main drivers of golden perch and Murray cod recovery following catastrophic fish kills. Interpreted in the context of other recent examples, the collective results indicate limited benefit of stocking to existing connected populations already naturally recruiting in riverine systems.

The Murray Cod Maccullochella peelii and Golden Perch Macquaria ambigua are important recreational species in Australia's Murray–Darling Basin (MDB); both species have declined substantially, but recovery is evident in some areas. Minimum length limits (MLLs)—implemented to ensure fish could spawn at least once prior to harvest eligibility—have increased three times in the past decade. We quantified variation in length at 50% maturity (LM50), age at 50% maturity (AM50), and von Bertalanffy growth parameters (k = Brody growth coefficient; L∞ = asymptotic length; t0 = theoretical age at zero length) of these species within two rivers and two reservoirs of the MDB; to investigate whether fish length is a suitable surrogate for AM50 in setting MLLs. Between 2006 and 2013, we collected 1,118 Murray Cod and 1,742 Golden Perch by electrofishing and gillnetting. Values of k and L∞ were greater for reservoir fish than for riverine fish. For both species, AM50 was generally greater in rivers than in reservoirs; for Murray Cod, LM50 was greater in reservoirs than in rivers. A yield‐per‐recruit model demonstrated that smaller Murray Cod MLLs would be required for rivers and that an MLL at or below 600 mm (the existing MLL) across all populations could lead to overfishing in some systems. The differences in growth rate and the onset of reproductive maturation between riverine and reservoir populations suggest that system‐specific regulations would be more effective at reducing the overfishing risk and meeting fishing quality objectives. Received August 18, 2014; accepted September 10, 2015

Recreational fishery management aims to prevent species decline and provide sustainable fisheries. Overfishing has been frequently suggested as a cause of historic fishery declines within the Murray–Darling Basin (MDB), Australia, but there have been few quantitative surveys for providing fishery‐dependent data to gauge status. The Murray Cod Maccullochella peelii and the Golden Perch Macquaria ambigua are important species targeted by recreational fishers across the MDB. The fisheries are controlled by size and bag limits and gear restrictions (both species) as well as a closed season (Murray Cod only). A complemented fisher survey design was used to assess the recreational fishery for both species in a 76‐km reach of the Murrumbidgee River in 2012–2013. Progressive counts were used to quantify boat‐ and shore‐based fishing effort. Catch and harvest rate information was obtained from shore‐based fishers via roving surveys and from boat‐based fishers via bus route surveys. Murray Cod catch rates (fish/angler‐hour) were 0.228 ± 0.047 (mean ± SE; boat based) and 0.092 ± 0.023 (shore based), and harvest rates (fish/angler‐hour) were 0.013 ± 0.006 (boat based) and 0.003 ± 0.001 (shore based). Golden Perch catch rates were 0.018 ± 0.009 (shore based) and 0.002 ± 0.001 (boat based), and harvest rates were 0.006 ± 0.002 (shore based) and 0.001 ± <0.001 (boat based). The Murray Cod fishery had maximal catch and harvest during the 5‐month period after the closed season ended. The closed season aims to protect spawning Murray Cod, but this strategy's effectiveness may have been influenced by high fishing effort and deliberate bycatch during the closure period. To sustain and improve these MDB fisheries, we suggest quantification of catch‐and‐release impacts on spawning Murray Cod, provision of fish passage, re‐stocking of Golden Perch, and education on fishing techniques that minimize Murray Cod bycatch during the closed season. Received October 22, 2014; accepted March 6, 2015