The main climate pressures affecting the marine environment in South Australia are changes in ocean temperatures, rainfall and ocean acidity. Understanding the effects of these changes can assist in understanding the likely impacts to coastal communities.
Increased ocean temperatures have a negative impact on commercial, recreational and charter fishing as well as shipping, ports and marinas in South Australia. These impacts are due to potential species range shifts, forcing some valuable and iconic species to move further south into cooler waters. Warmer waters may also increase the prevalence and survival of pests and diseases. Additional regulations may be placed on shipping, and monitoring/remediation may be required to deal with pests and diseases in ports and marinas.
Rack and pen-based aquaculture are negatively affected by changes in rainfall, particularly flood events. Floods wash bacteria, nutrients and pesticides into coastal waters which can affect aquaculture production. Rack-based aquaculture in South Australia may also be negatively impacted by increased ocean acidity which can soften the shells of mussels and oysters.
High value species
South Australia had the highest wild capture commercial fishery production in Australia (43 132 t, 2010/11) and the second highest overall commercial fishery value (approximately $200m). The most valuable species captured was the southern rock lobster (over $81m) followed by prawns (approximately $34m) and abalone (approximately $28m). Similar to Victoria, the highest tonnage was for the lower valued sardines (33 220 t, almost $2m) followed by prawns (2293 t) and southern rock lobster (1557 t). The international export market for rock lobster and abalone, in particular, help to keep the value of those species high in comparison to sardines which are mainly (94%) used for tuna feed in SA’s aquaculture sector.
In 2010/11, South Australia’s aquaculture sector was the second most valuable in Australia (approximately $230m), behind Tasmania (approximately $430m). Southern bluefin tuna have the highest value of all aquaculture species in SA (over $125m). Oysters were the second most valuable aquaculture species (over $36m) and had a greater production (6154 t) than tuna (approximately 5800 t) in 2010/11. Other species farmed in aquaculture in SA include blue mussels, marron and yabbies, and abalone.
A study into recreational and Indigenous fishing found that approximately 24% of South Australians participated in recreational fishing between May 1999 and May 2000 (Henry and Lyle 2003). This was approximately equivalent with Queensland and behind the Northern Territory, Tasmania and Western Australia. These fishers catch mainly King George whiting, squid/cuttlefish, blue swimmer crab, Australian salmon and pink snapper.
In addition to fishing and aquaculture, South Australia has a relatively small but active shipping/sea freight industry as well as marine tourism and employment in ports and yacht clubs.
The shipping and sea freight industry in SA ranks sixth of all Australian states and territories with only Tasmania ranked lower. The approximate value of exports and imports shipped from SA ports in 2010/11 was just over $100m. Accordingly, the number of people employed in SA’s ports was relatively small at approximately 190 or 7% of the Australian total.
Whale watching in SA is relatively popular with 7 operators and nearly 200 000 participants in 2010/11. Both the number of whale watching participants and number of yacht clubs (39) were ranked fourth of all Australian coastal states and territories.
Climate and sealife
See Climate and sealife – species sensitivities page for detailed information