Irukandji threat to southern waters

Oct 28, 2013

A Griffith University led study has made the surprising discovery that ocean acidification may provide some protection for South East Queenslanders from the Irukandji jellyfish.

Researchers from Griffith University's Australian Rivers Institute have conducted a series of climate change simulation experiments to investigate whether the dangerous tropical jellyfish, the Irukandji, is likely to establish breeding populations in the South East.

It was found that while higher sea temperatures could provide an opportunity for adult Irukandji to expand their range south, increasing may inhibit the development of juveniles.

The research is the first step towards assessing if Irukandji pose a significant threat to tourism and human health in the South East. The findings have been published in the journal Global Change Biology.

Lead author, Griffith PhD student Shannon Klein said concerns have arisen from evidence world-wide that tropical marine species are moving towards the poles as oceans warm.

"Increasing ocean temperatures and strengthening boundary currents have caused the poleward migration of many ," Shannon Klein said.

"These effects of are particularly apparent on the eastern coast of Australia. Over the past 60 years the East Australian Current (EAC) has strengthened and now delivers warmer tropical waters further south by as much as 350km."

As a consequence at least five species of tropical fish that occur on the Great Barrier Reef (GBR) are predicted to be able of survive winter temperatures in waters off Sydney by 2080. Among all species that could potentially expand their range south, the Irukandji would arguably have one of the greatest socio-economic impacts.

Irukandji have historically been limited to waters north of Gladstone, however in 2007 an adult specimen was recorded for the first time as far south as Hervey Bay.

"What we needed to find out was if the Irukandji would be able to establish their entire lifecycle south of their historical range in these expanded reaches of warm water or if adults only are able to drift south on the strengthened current," Shannon said.

As it turns out the role of ocean acidification in limiting reproduction may hold the key to protecting the SE Queensland coastline. But we may not be out of hot water just yet.

"This response may reduce the likelihood of Irukandji jellyfish establishing permanent populations in South East Queensland in the long term, however, it is possible that they could migrate farther south in the short term if acidification proceeds slowly and appropriate reproduction habitats are available.

"But even if juvenile populations remain confined to more northerly waters there is still the strengthening EAC which could carry adults south."

Irukandji jellyfish are represented by at least six species of cubozoan jellyfish which occur throughout the world's tropical zones, so the implications of this study are far reaching.

"Our results suggest that, if other Irukandji behave similarly, range expansions could be occurring in other regions around the globe," Shannon said.

Explore further: Satellite catches lingering remnants of Tropical Depression 9

add to favorites email to friend print save as pdf

Related Stories

Marine life spawns sooner as oceans warm

Aug 06, 2013

Warming oceans are impacting the breeding patterns and habitat of marine life, effectively re-arranging the broader marine landscape as species adjust to a changing climate, according to a three-year international ...

Tropical vagrants bigger, stronger survivors

Jun 12, 2013

(Phys.org) —Sydney marine researchers are one step further in solving the mystery of how tropical fishes, in response to rising sea temperatures and the impact of climate change, are shifting, and potentially ...

Climate change plays 'Russian roulette' with the world's oceans

Oct 16, 2013

The world's oceans will see dramatic changes thanks to climate change, affecting hundreds of millions of people who depend on the sea according to research published today in the online journal PLOS Biology. It's the first global forecast for the oceans under clim ...

Corals 'can fight acidifying oceans'

Oct 11, 2013

In a world-first, scientists from the ARC Centre of Excellence for Coral Reef Studies (CoECRS) have shown that tropical corals have the ability to fight back against acidifying oceans caused by human emissions of carbon dioxide.

Recommended for you

Icelandic volcano sits on massive magma hot spot

14 hours ago

Spectacular eruptions at Bárðarbunga volcano in central Iceland have been spewing lava continuously since Aug. 31. Massive amounts of erupting lava are connected to the destruction of supercontinents and ...

NASA sees Tropical Storm Ana still vigorous

16 hours ago

NASA's TRMM satellite saw that Tropical Storm Ana was still generating moderate rainfall is it pulled away from Hawaii. The next day, NASA's Aqua satellite saw that wind shear was having an effect on the ...

User comments : 0