You soon may not have to embark on a northern holiday to encounter schools of tropical fish, a marine expert says.
“I think there is already plenty of evidence tropical and sub-tropical fish are already further south,” independent marine biologist Dr Murray MacDonald said after 2016 saw record sea-surface temperatures around the nation.
“Recent reports show sea surface temperatures on average have increased by one per cent since pre-industrial days.”
Dr MacDonald said the shift will see continued changes in communities of plants and animals and an increase in those more tolerant to warmer waters on the Far South Coast.
One example is the essentially cool water loving large brown kelp having seen a noticeable decline over the last 20 to 30 years, he said.
“They tend to attach to hard surfaces, and have been disappearing from reefs with other species such as urchins taking over and becoming more prevalent as they no longer have to compete,” Dr MacDonald said.
Dr MacDonald said the shift is due to the East Australia Current becoming warmer and more persistent.
“Those monitoring, primarily the CSIRO have seen the strength of the East Australia Current is staying stronger for longer, persisting for longer and moving further south,” he said.
Dr MacDonald said citizen science websites such as the Range Extension Database and Mapping project – Redmap - founded and run by Dr Gretta Pecl from the Institute for Marine and Antarctic Studies at the University of Tasmania, are becoming more important than ever.
“Increasingly in the era of government restricting science budgets, citizen science increasingly has its place,” Dr MacDonald said.
“It sees teams of scientists providing legitimacy to information on the documented shift in species.”
The CSIRO’s State of the Climate report for 2016 found oceans around Australia have become warmer with an increased level of acidity.
The report states the areas with the greatest surface warming are to the west and south of Australia.
