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Impacts on CPUE from vessel fleet composition changes in an Australian lobster ( Jasus edwardsii ) fisheryNARA Subscribed
The Australian Victorian Western Zone rock lobster fishery is assessed using standardised catch‐per‐unit‐effort (CPUE). Nominal CPUE declined over 1978–2009, but this underrepresents the estimated decline in abundance, and since 2009 standardised CPUE rose notably less than nominal CPUE. This study identified vessel as a key factor that explains the discrepancy between nominal and standardised CPUE. The composition of the flee...
The degree to which a stock is depleted is one of the most important quantities in fisheries management because it is used to quantify the success of management and to inform management responses. However, stock depletion is extremely difficult to estimate, particularly with limited data. Using the RAM Legacy database, we developed a boosted regression tree ( BRT ) model to correlate depletion with a range of predictors calcul...
Trends and management implications of human‐influenced life‐history changes in marine ectothermsNARA Subscribed
Evidence is accumulating that many marine ectotherms are undergoing rapid changes in their life‐history characteristics. These changes have been variously attributed to fisheries‐induced evolution, inhibited adult growth rate due to oxygen limitation at higher temperatures, and plastic responses to density dependence or changes in ocean productivity. Here, we review the diverse underlying mechanisms by which plastic and evolut...
Is risk consistent across tier‐based harvest control rule management systems? A comparison of four case‐studiesNARA Subscribed
There can be substantial differences in data quality and quantity among fished species. Consequently, the quality and type of assessments can also vary substantially. However, all species, especially those that are targeted, need to be managed. Several jurisdictions have developed hierarchical tier systems that categorize stocks based on, for example, the data available for assessment purposes and/or the extent to which quanti...
Management strategy evaluation: best practicesNARA Subscribed
Management strategy evaluation ( MSE ) involves using simulation to compare the relative effectiveness for achieving management objectives of different combinations of data collection schemes, methods of analysis and subsequent processes leading to management actions. MSE can be used to identify a ‘best’ management strategy among a set of candidate strategies, or to determine how well an existing strategy performs. The ability...
Modelling climate‐change‐induced nonlinear thresholds in cephalopod population dynamicsNARA Subscribed
A significant global challenge lies in our current inability to anticipate, and therefore prepare for, critical ecological thresholds (i.e. tipping points in ecosystems). This deficit stems largely from an inadequate understanding of the many complex interactions between species and the environment at the ecosystem level, and the paucity of mechanistic models relating environment to population dynamics at the species level. In...
The relationship between the level of octopus ( Octopus maorum ) predation and the daily‐average number of lobsters ( Jasus edwardsii ) per pot was investigated using commercial catch statistics. Octopus predation was found to be inversely correlated with lobster catches, such that, lobsters experienced reduced survival when their daily‐average density in a pot was lower. The reduction in survival at lower densities provides e...
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