A changing climate will impact on the water and food sources that support aquatic life.

The Marine Climate Change Impacts and Adaptation Report Card for Australia provides a guide for industry, scientists, government and the community on the observed and projected impacts of climate change on marine ecosystems. The report card was developed by leading marine scientists from across Australia. Some of the key findings include:

  • Australian ocean temperatures are likely to be 1 degree warmer by 2030 and 2.5 degrees warmer by the end of the century.
  • There has been a 30 per cent increase in hydrogen ion (acid) concentration in oceans since 1750 and this is associated with the amount of carbon dioxide absorbed.
  • The southward flow of the East Australian Current has strengthened so that warmer, saltier water is now found 350 kilometres further south compared with 60 years ago.
  • Global sea levels increased by 20 centimetres between 1870 and 2004.
  • Declines of over 10 per cent in growth rates of massive corals on the Great Barrier Reef are likely due to ocean acidification and thermal stress.
  • Loss of algal habitat off eastern Tasmania associated with a southward range expansion of a sea urchin has been assisted by the strengthening of the East Australian Current and warmer temperatures.
  • Expansion of sub-tropical species, into south-eastern waters is driven by warming and a strengthening of the East Australian Current.

 
Annual & ten year mean sea surface temperature for the Australian region. Source: Bureau of Meterology 2010

 

Resource managers need to appreciate change is here and they need to put in place adaptive strategies to deal with it.

Ocean acidification and increased thermal stress are the likely causes of slower growth rates of corals and this may mean greater susceptibility to storm disturbance and loss of diversity. Sea level rises will also disrupt the ecosystem causing an expected expansion of mangrove areas and a decline in sea grasses in some areas. Upstream movement of water into estuaries will affect juvenile stages of many species, including prawns, while changing areas suited to oyster culture.

These issues show that fishing and aquaculture activities, management and planning will need to be flexible because of changes to habitats, populations, movement, feeding opportunities, aggregations and breeding cycles.

Ocean acidification and increased thermal stress are the likely causes of slower growth rates of corals and this may mean greater susceptibility to storm disturbance and loss of diversity. Sea level rises will also disrupt the ecosystem causing an expected expansion of mangrove areas and a decline in sea grasses in some areas. Upstream movement of water into estuaries will affect juvenile stages of many species, including prawns, while changing areas suited to oyster culture.

These issues show that fishing and aquaculture activities, management and planning will need to be flexible because of changes to habitats, populations, movement, feeding opportunities, aggregations and breeding cycles.​​