Department of Primary Industries and Regional Development (DPIRD) researchers are delivering presentations on how fisheries management measures can reduce impacts on marine ecosystems.
DPIRD’s Aquatic Science and Assessment team’s lobster and crab research is being shared at a high-profile fisheries conference in Fremantle this week. The 2023 International Conference on Lobster (and Crab) Biology and Management has brought together 189 fisheries scientists, managers, and stakeholders from 18 countries.
Whale entanglements in fishing gear is a sensitive issue worldwide and DPIRD Principal Research Scientist Jason How will be speaking about how keeping WA’s range of fish stocks abundant and sustainable is a vital part of reducing the risk of entanglements.
“Where fish stocks are in a healthy state, lower levels of fishing effort are required by fishers to obtain the same level of catch in output-controlled fisheries or greater catches for the same level of effort for input-controlled fisheries,” Dr How said.
“In WA’s rock lobster fishery, where fishers are changing behaviour to maximise cash flow or minimise unfished quote, there is opportunity to reduce the risk of whale entanglements through high stock abundances or changing the end dates of year-round fishing seasons.”
Fisheries management globally must also respond to the shifting nature of human pressures and a changing climate. Prudent management has ensured sustainability of the blue swimmer crab fishery in the Swan-Canning Estuary.
DPIRD scientists have documented the evolution of the commercial and recreational crab fishing sectors in the estuary over more than 100 years. The recreational catch has grown over time and now forms the major component of this iconic blue swimmer crab fishery.
DPIRD Research Scientist David Harris said that along with the impacts of a changing climate, urban development and extensive historical modifications to the Swan-Canning Estuary have had a significant impact on the composition of the commercial catch.
“Whereas finfish species once accounted for the majority of landings in the fishery, habitat modification, hypoxia, increased marine conditions and changing market demand have seen blue swimmer crab emerge as the primary component of the Swan-Canning catch in recent years,” Mr Harris said.
“An understanding of how these processes have affected individual species can provide management with valuable insights into the likely effect projected changes to the environment may have on fishery stock dynamics into the future.”
The 12th International Lobster and Crab Conference will continue through until Friday at the Esplanade Hotel in Fremantle.