CANBERRA, June 12 (Xinhua) -- Northern Australia's shallow tropical gulfs and bays are experiencing complex and intensifying impacts from climate change, with some marine species unable to shift to cooler waters due to geographic barriers, new research shows.
A study published in Science, led by the Commonwealth Scientific and Industrial Research Organization (CSIRO), Australia's national science agency, examined ecosystems in the Gulf of Carpentaria, Joseph Bonaparte Gulf and Torres Strait in northern Australia and found that ocean temperature is not the only important indicator of climate change.
Researchers identified combinations of four key factors shaping species outcomes: extreme temperatures, exposure to dehydration, water turbidity and disruptions to natural water flows. These patterns of change are largely influenced by El Nino or La Nina weather events.
"Species are riding more extreme climate rollercoasters, with steeper and larger changes in the marine environment hindering their recovery," lead author Eva Plaganyi, a senior principal research scientist at CSIRO, wrote in an article published on Friday.
Northern Australia's seagrasses and mangroves support threatened species including sawfish, dugongs, turtles and snubfin dolphins.
The study found contrasting responses among commercially important species. Brown tiger prawns, dubbed "Goldilocks" species for their narrow habitat needs, have declined since the late 1990s. More frequent La Nina events, increased cyclones and river flooding have damaged their seagrass nursery habitat.
In contrast, banana prawns have thrived under favorable river-flow conditions but face risks during El Nino periods when dry weather and lower sea levels disrupt river-ocean connections they rely on, the study warns.
Researchers say the findings will help fisheries and conservation managers prepare for compound climate events, particularly as an extreme El Nino is forecast later this year. ■
