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Context: Successful fish stocking relies upon releasing cohorts directly into habitat containing suitable supporting resources. To facilitate this, an emerging trend has seen fish released onto artificial reefs. Aims: We compared the residency and movement patterns of juvenile sparids (yellowfin bream – Acanthopagrus australis), stocked on artificial reefs and natural habitat, to determine the suitability of incorporating artificial structures as release sites in future stocking programs. Methods: Forty hatchery-reared yellowfin bream were evenly divided and stocked on either artificial reef or natural habitat within an east-Australian estuary, and tracked using acoustic telemetry. Key results: Artificial reefs provided greater habitat complexity than the natural habitat and fish stocked onto these structures showed greater fidelity to their release site and were detected for longer periods of time than those stocked into less complex natural habitat. Conclusions: The high residency levels of fish around artificial reef sites indicate they contain resources to support stocked juvenile sparids. Implications: Stocked yellowfin bream can tolerate a range of salinity and temperatures, allowing flexibility in stocking programs. Future stocking of bream or other sparids should consider releasing fish onto artificial reefs where available. Additionally, the deployment of reefs could aid existing stocking programs. Successful fish stocking relies upon releasing cohorts directly into habitat containing suitable supporting resources. We compared residency and movement patterns of juvenile yellowfin bream stocked on artificial reefs and less complex natural habitat. Fish stocked on artificial reefs showed greater fidelity to their release site and were detected for longer periods. Future stocking of bream or other sparids should consider releasing fish onto artificial reefs, with benefits these structures provide likely to be greater for estuaries lacking naturally complex habitats. [ABSTRACT FROM AUTHOR]

Stocking of marine fish into coastal systems to augment natural recruitment is a growing practice adopted by fisheries managers around the world. Releasing fish directly into well‐resourced nursery grounds greatly increases survival and retention of stocked individuals but requires an understanding of juvenile habitat requirements. In eastern Australia, the dusky flathead (Platycephalus fuscus) is a highly regarded recreationally targeted species and the focus of an emerging stock enhancement programme, although little is known of their specific nursery habitat. Using acoustic telemetry, hatchery‐reared juveniles were monitored in Lake Macquarie to quantify habitat use and dispersal. Sandy areas adjacent to edges of seagrass beds were favoured, likely as foraging habitat. Within 5 weeks after release, fish were detected 5 km from the release site, but only at locations containing seagrass beds, so stocked fish likely disperse around estuaries to regions with suitable habitat. Future releases of dusky flathead should target areas containing patchy seagrass‐sand to optimise stocking outcomes. Beyond fisheries enhancement programmes, our findings highlight the importance of structured habitat, such as seagrass beds, for juvenile fish. [ABSTRACT FROM AUTHOR]

The present study investigated the long-term (>2 years) site fidelity, residency and movement patterns of Acanthopagrus australis (Sparidae) at artificial (AR) and natural reef (NR) sites. Acoustic telemetry was used to assess movement patterns of 39 fish released at NR and AR locations and other habitat types within the study area. Detection periods ranged from 1 day to a maximum of 912 days, with 36% of fish detected by the array for.1 year and a further 7% detected for>2 years. Results indicate that tagged fish tended to remain associated with the release site; however, AR fish were detected for considerably longer periods with greater numbers of fish identified as resident within the AR system. AR-released fish were also identified more frequently across the entire array, with the majority (90%) of detections between receiver stations located within the AR system. Results were affected by short detection periods (<6 days) of a relatively high proportion of fish released at the NR, possibly indicating differential rates of fishing mortality between locations. Longer range movements of>200 km were also detected, but there was no obvious trend with release location. The results of the present study indicate interactions between existing and introduced artificial habitat are more complex than a 'draw-down' effect and provide further evidence that AR systems provide suitable habitat for a variety of species, as well as further support for the use of AR systems in fisheries enhancement initiatives. The results also have important implications for understanding the effect of AR systems and indicate that the size of the reef system may be an important factor in controlling for levels of fishing-related mortality. [ABSTRACT FROM AUTHOR]

Artificial reefs now form part of an integrated approach to enhance fisheries around the world. A responsible approach to artificial reef deployment calls for clear, well defined goals prior to any reef being placed in the field, followed by subsequent monitoring to assess whether these goals are being achieved. In this study, to evaluate if an artificial reef off Sydney was meeting its goal of providing quality fishing opportunities through the establishment of a complex fish assemblage, a 4-year monitoring program was designed. This program examined the response of reef-associated and pelagic fishes to the deployment of a purpose built offshore reef, relative to control reefs. Fish were observed immediately following deployment, but the artificial reef fish assemblage remained distinct from the three natural control reefs throughout the monitoring period. Also, the artificial reef displayed inter-annual variability associated with successional processes, which was not evident on the natural reefs. Fish length data indicated that the artificial reef was providing resources for both juvenile and adults of a number of species. This study demonstrates artificial reefs can provide habitats for a diverse group of fish, but the assemblages are unlikely to mimic those on natural reefs. We have also shown that longer term monitoring periods, covering multiple years are required to gain a robust understanding of the response of fish to reef deployment. This information can be used to understand the benefits and limitations of future artificial reef deployments. [ABSTRACT FROM AUTHOR]