Cumulative impacts across fisheries in Australia's marine environment
The need for cumulative impact assessment (CIA) is increasingly being recognized. The development process for Australia's Harvest and Bycatch Policies, and their associated guidelines have reinforced the need for assessment of cumulative impacts, and the EPBC Act has also explicitly required consideration of cumulative impacts.
Where multiple activities occur or are planned, an understanding of their combined effects on the environment is necessary to address policy requirements and achieve sustainability. The concept of cumulative impact assessment is not new – indeed cumulative assessment has been recognized for many years, and a range of methods have been proposed around the globe. However, no methodology for undertaking cumulative assessments has been accepted nationally or globally. In addition to considering the impacts across all fishing sectors (commercial, recreational, indigenous, as required by recent changes to the Fisheries Administration Act 1991) and all fisheries, there is also an increasing need to consider other users of marine resources and coastal waters (e.g. renewable energy, shipping etc), especially where space crowding may be an issue.
Target species stock assessments typically consider the species of interest as well as other sources of fishing mortality (e.g. discards), but they do not usually consider their effects on other fisheries sectors or the effects of other sectors on the focal fishery. CIA methods therefore need to consider interactive and indirect effects. To date, interactive effects are often viewed as additive (simple linear addition of one impact to another) with little consideration given to synergistic, antagonistic or non-linear effects. While the ERAEF toolbox used for assessment of bycatch and protected species has some potential options for cumulative impacts (e.g. SAFE method), at this stage they are insufficient for moving to the scales and complexities across multiple fishing sectors and fisheries.
Thus, sustainable fisheries management requires new approaches that consider all sectors and all fisheries and how they impact the environment. Such CIAs will be challenging given that empirical data are often lacking - a dedicated research effort is needed.
Final report
Compilation of information for the US Marine Mammal Protection Act Comparability Finding process
The Department of Agriculture, Water and Environment require relevant information be collated on marine mammal populations that interact with fisheries classified as 'export' under the provisions of the US Marine Mammal Proection Act.
The Department of Agriculture, Water and Environment have listed several marine mammal species for which mortalities have been recorded in Australian fisheries and require an estimate of Nmin, Rmax and Fr for each of these species in order to determine for which a PBR approach is currently feasible. Data deficiencies that prevent PBR being calculated for a given species need to be determined and potential approaches to obtain relevant information identified.
If PBR is not a feasible approach to be undertaken for any of the marine mammal species identified, other relevant data for each species and 'export' fishery will need to collated in order for NOAA to be able to determine if a comparability finding for that fishery can be granted. This could include information on the level of monitoring in that fishery, temporal or spatial overlap with the marine mammals species and existing management of interactions such as fishery specific bycatch management strategies.
Final report
Several Australian commercial fisheries have received an ‘exempt’ classification under the MMPA import provisions which means they have been determined to have a remote likelihood, or no known incidental mortality of marine mammals. The remaining fisheries that are seeking a comparability finding have been classified as ‘export’ fisheries as they were determined to have more than a likelihood of incidental mortality to marine mammals. For each of these fisheries, the US requires information on monitoring programs in the fishery, levels of marine mammal bycatch, the species and ‘stocks’ (populations) involved, and the management strategies in place to mitigate bycatch.
This report synthesises the required information for 15 Australian Commonwealth managed commercial fisheries or fishery subsectors, and 29 Australian State and Territory commercial fisheries that are seeking a comparability finding under the US MMPA. Reports and / or observations of marine mammal interactions in Australian commercial fisheries that are not seeking export approval are also synthesised as this information is also required as part of the comparability finding process.