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'Window to the Future' for Rocklobster industry
SARDI research, supported by State Government has opened a ‘window to the future’ for South Australia’s Rocklobster industry by providing a strategic insight into the success of future seasons up to five years in advance.
Above: SARDI scientist Dr Adrian Linnane with rock lobster
Fisheries Minister Gail Gago said the improved catch rates currently being observed this season in the Southern Zone Rocklobster fishery were predicted several years ago by SARDI scientists based on the monitoring of Rocklobster larvae called puerulus.
“Very few fisheries have the luxury of knowing what is likely to happen so far in advance, and therefore the ability to intervene early to ensure the fishery remains healthy and sustainable,” Ms Gago said.
Southern Zone Rocklobster fishers have already caught 60% of their 1250 tonne quota just three months into the eight month season, while Northern Zone Rocklobster fishers have caught 50% of their 310 tonne quota in just two months.
“Given the decline in the Southern Zone Rocklobster’s fishery status over recent seasons, it is important that we afford protection to the pulse of recruits currently entering the fishery,” Ms Gago said.
“This will allow the Rocklobster biomass to rebuild and thus ensure that the fishery remains sustainable into the future.”
SARDI scientist, Dr Adrian Linnane said high levels of puerulus were observed across all study sites in 2005 and 2006.
“In the Southern Zone it takes five years for a puerulus to grow to adult size,” Dr Linnane said.
“We were therefore able to advise PIRSA Fisheries and Aquaculture managers and industry stakeholders that while the fishery had declined in recent seasons, things would likely improve in 2010 and 2011.
“These predictions proved to be correct, with catch rates increasing by 56% in 2010 and by a further 20% thus far in 2011.”
SARDI researchers have been monitoring puerulus across the Southern and Northern Zone Rocklobster fishing areas since the mid 1990s, using collectors that mimic the reefs puerulus naturally settle in.
Dr Linnane said the collectors were located at sites all around the coast from Port MacDonnell to Port Lincoln, and they were checked every month on the full moon when puerulus settlement is highest.
Rocklobsters in captivity have been known to survive for up to 35 years. Their reproductive life spans between 10 and 15 years, and while female Rocklobsters can carry up to 600 000 eggs at a time, only 1% survive to become adults.
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Puerulus 12 to 24 months
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Puerulus 12 to 24 months with fully grown lobster
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While the puerulus monitoring has proven to be a valuable predictive tool, the results are not directly used by PIRSA Fisheries and Aquaculture to set the annual total allowable commercial catch (TACC) limit. The two key biological performance indicators used to set the TACC are commercial catch rates of pre-recruit (undersized) and legal sized lobsters.
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Puerulus 12 to 24 months
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Puerulus sighted in puerulus collectors
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It is widely acknowledged that the Southern Zone Rocklobster fishery is one of the best managed in the world. Commercial fishers make extremely valuable contributions to the research effort by helping with voluntary pot sampling, survey work and providing information on tagged lobsters. Puerulus monitoring is funded by Rocklobster fishers through licence fees.
Photos available at www.sardi.sa.gov.au
Dr Adrian Linnane with rock lobster (High resolution)
Puerulus 12 to 24 months (High resolution)
Puerulus 12 to 24 months with fully grown lobster (High resolution)
Further information: Dr Adrian Linnane. Ph: 8207 5492 or 0423 027 357
SARDI Communications: Terry Price. Ph: 8303 9433 or 0423 292867
