Tiger Prawn

• Commonwealth Northern Prawn Fishery (1,247t in 2021)

Tiger prawns are found from inshore shallow estuarine and intertidal areas to the continental shelf depths of ~200m from the Gascoyne in WA, throughout northern Australia to the northern coast of NSW. They live in turbid waters most of their lives, inhabiting sheltered mangrove creeks as juveniles before moving to coastal sandy and muddy habitats as adults.

The name ‘tiger prawn’ refers to two species – grooved and brown tiger prawns. These two species live in tropical waters and are short-lived and fast-growing. Both species are caught in the Commonwealth-managed Northern Prawn Fishery.

There have been some recent concerns that the brown tiger prawn population targeted in the fishery is slightly below a healthy level, but it is not likely that overfishing is still occurring, and there is evidence of recovery. Similarly, the grooved tiger prawn population is below a healthy level, and measures of juvenile abundance have been concerning. It is notable that environmental factors are highly important in influencing the abundance of tiger prawns (especially wet season rainfall, and it is welcome that fishery management considers these environmental factors) and it is considered unlikely that overfishing is occurring.

Prawns are caught using otter trawls that operate on the seabed, mainly over mud and sand. This has the potential to cause significant habitat disturbance. Habitat types are relatively well understood in all fishing areas, tend not to support sensitive marine communities and are fairly resilient to disturbance.

Marine parks established in 2018 across northern Australian offshore waters may provide a small degree of additional protection for habitats and bycatch species, though it is notable that the fishing industry secured significant reductions in the area of the fishery protected from trawling in a way that has considerably weakened the effectiveness of these protections and has not been accounted for or addressed in other management.

Bycatch reduction devices (BRD) and Turtle Exclusion Devices (TEDs) reduce the amount of threatened and other species that are caught and killed in fishing gear. BRDs and TEDs are mandatory in all these fisheries and have been successful in reducing turtle deaths. However, threatened species bycatch remains an ongoing issue.

The main Commonwealth fishery has been proactive in attempting to reduce its impacts on threatened species. Although catch of sea snakes remains high, there are no indications that fishing activity is resulting in population declines of any of the species caught. Endangered sawfish, particularly narrow sawfish, are caught every year, although it is complex to design modified fishing gear to reduce sawfish mortalities because the shape of their rostrums means they are especially prone to entanglement. Due to the wide distribution of sawfish, including in non-fished areas, experts have assessed that prawn fishing alone is not driving further declines in these species, but further significant reductions in sawfish bycatch will be required in future.

The Commonwealth-managed prawn fisheries have robust and transparent management arrangements in place, including observer programs, requirements to report discards, assessments of the risk of the fishery to threatened species, plans in place to reduce bycatch that have proved to successfully deliver that objective and management actions to rectify issues in the fishery when they occur. It is likely these management arrangements will maintain the progress of these fisheries to reduce the impact on endangered wildlife in the future.