Fisheries scientists with the Department of Primary Industries and Regional Development are researching new methods to forecast future stocks of western rock lobster in WA.
Fisheries scientists with the Department of Primary Industries and Regional Development are researching new methods to forecast future stocks of western rock lobster in WA.
The work is modelling different climate scenarios against phyllosoma (larval lobster) dispersal and settlement to ocean circulation and productivity.
The modelling is part of ongoing research with the University of Western Australia and CSIRO, funded by the Fisheries Research and Development Corporation on behalf of the Australian Government and the Western Rock Lobster Council.
Speaking during National Science Week, DPIRD Principal Research Scientist Simon de Lestang said monitoring of the larval settlement stage (puerulus) had been undertaken in Western Australia since 1969 using world first techniques.
Monitoring juvenile settlement provides an indication of adult stock abundance in four years’ time – this type of research is unique to the rock lobster fishery.
Dr de Lestang said the research was now focussed on developing new ways to forecast how big and productive puerulus settlements would be under future climate scenarios.
“DPIRD’s long-term puerulus monitoring stations between Kalbarri to Margaret River will form the basis of model calibrations and validations,” he said.
“The eight monitoring sites have been used for 58 years to monitor puerulus settlement, using artificial seagrass collection stations.
“We are assessing future puerulus settlement patterns under different climate scenarios, considering anticipated changes in oceanic conditions, including warming water temperatures, and their likely impacts on ocean productivity.
“Multiple simulations with differing parameters will be performed to provide a range of realistic future outcomes.”
Dr de Lestang said warmer water temperatures were associated with greater settlement success by increasing growth rates and decreasing the length of the larval phase, minimising natural mortality.
“The project aims to provide plausible future scenarios of puerulus settlement and larval dispersal under future climate projections and explore the implications of these findings for the western rock lobster fishery,” he said.
“Future outlooks for the fishery will contribute to its successful and ongoing sustainable management and provide a record of potential impacts for current and future managers, fishers and stakeholders.”
