Department of Fisheries research monitoring shows that stocks, in the Roe’s abalone fishery along the Perth metropolitan coast, have not recovered from 2012’s large decline.
South West Bioregions Manager Tim Nicholas says the warmer than average coastal sea temperatures in recent years since the marine heatwave of 2010/11 appears to have had an impact on the growth rate of abalone and significantly slowed or stunted development.
“Given these environmental factors, the usual fishing pressure that occurs along the Perth coast during the limited recreational fishing season for abalone, cannot be supported with the current level of recruitment of Roe’s abalone into the fishery,” Mr Nicholas said.
“As a result, we have to take a cautious approach for the 2014/15 fishing season and reduce the bag limit in the West Coast Zone to reduce the potential for more serious stock depletion and more significant management action.
“The season will still run for five one hour fishing windows between 7am and 8am on the first Sunday of each month from November to March, but the bag limit for licensed abalone fishers on each of those days will change from 20 to 15. It is expected that these changes will be gazetted this month.
“While we cannot control environmental factors, we can manage fishing effort, so if all fishers stick to the new bag limit then the season can still be enjoyed across five Sundays.”
Senior research scientist and abalone specialist Dr Anthony Hart said the marine heatwave all but wiped out some of WA’s northern stocks, forcing the closure of commercial and recreational abalone fishing north of Moore River until further notice.
“It has also become obvious that the State’s more southern stocks of Roe’s abalone, the species common along the Perth coast, didn’t escape unscathed either,” Dr Hart said.
“What’s been obvious is the lack of the larger sized abalone in both fished and unfished areas, which indicates that growth of many abalone may have been dramatically slowed.
“There’s also been a significant negative effect on the reproductive success of the Perth abalone stocks, with post-heatwave years 2012 – 2014 being the worst ever for young abalone (Age 0+) in fished and unfished areas. This will mean fewer adults in the future.
“Research teams and volunteers will have to closely monitor the fishery, during and after each one hour fishing window, to measure the impact of the fishing on the stocks.”
Detailed information on abalone fishing in Western Australia, including season dates and rules to follow in the open section of the West Coast Zone, is available in the Recreational fishing for abalone guide 2014/15.