Everything you need to know about our oceans, and why they matter

What is South Australia’s ocean?

South Aus­tralia doesn’t have one ocean but three! The Antarc­tic, Indi­an and Pacif­ic Ocean all meet and inter­mix off South­ern Aus­tralia cre­at­ing an amaz­ing dynam­ic envi­ron­ment that influ­ences every aspect of our lives from the weath­er we expe­ri­ence, to the coastal envi­ron­ment we enjoy and the food we eat.

Here are 5 inter­est­ing facts about South Australia’s por­tion of the South­ern Ocean,

1. Warm water inputs: In the west­ern por­tion of South Australia’s ocean waters, tem­per­a­tures are influ­enced by a warm water cur­rent from West­ern Aus­tralia called the Leeuwin Cur­rent. These warm cur­rents allow some high­ly mobile fish species typ­i­cal­ly of trop­i­cal ori­gin to be observed in the Great Aus­tralian Bight.
2. Cold water inputs: The Great South Aus­tralian Coastal Upwelling Sys­tem is respon­si­ble for bring­ing nutri­ent rich cold water to the sur­face cre­at­ing phy­to­plank­ton blooms and pro­vid­ing key food sources for krill and sar­dines which are in turn impor­tant food sources for whales and fish like tuna.
3. Sig­nif­i­cant car­bon sink: The South­ern Ocean is a major car­bon sink, absorb­ing more car­bon diox­ide than it emits. This helps mit­i­gate the effects of cli­mate change by reduc­ing the amount of CO2 in the atmos­phere. It’s esti­mat­ed that the South­ern Ocean absorbs about 30% of the human-pro­duced CO2 in the world’s oceans.
4. Great South­ern Reef: The great south­ern reef stretch­es from WA to NSW and sup­ports amaz­ing marine bio­di­ver­si­ty, much of which is found nowhere else on the plan­et. SA’s ocean­ic waters help sup­ply nutri­ent, oxy­gen, and food to the GSR where you can find blue grop­ers, leafy see drag­ons, giant cut­tle­fish and a host of sharks and ray species. There is also an incred­i­ble vari­ety of life grow­ing on the GSR, includ­ing macroal­gae, sponges, crus­taceans, bry­ozoans, echin­o­derms, and molluscs.
5. Marine parks: South Aus­tralian waters are pro­tect­ed by a net­work of 19 marine parks in state waters, and 7 Aus­tralian marine parks in Com­mon­wealth waters. Both marine parks net­works are an impor­tant tool for con­serv­ing marine biodiversity

Why are oceans important?

Accord­ing to the UN, there are 5 main rea­sons to care about our oceans,

1. Cli­mate reg­u­la­tion: The ocean absorbs 25% of car­bon emis­sions and gen­er­ates 50% of our oxy­gen, help­ing to com­bat cli­mate change.
2. Food source: It pro­vides 15% of the ani­mal pro­tein con­sumed glob­al­ly, essen­tial for many populations.
3. Jobs and liveli­hoods: 3 bil­lion peo­ple depend on the ocean for their livelihoods.
4. Eco­nom­ic devel­op­ment: The ocean econ­o­my is val­ued at $3 tril­lion annu­al­ly, dri­ving sig­nif­i­cant eco­nom­ic growth.
5. Sur­vival: A healthy ocean is cru­cial for our over­all well-being and survival.

Why do oceans need to be saved?

Our oceans are fac­ing sig­nif­i­cant threats due to a com­bi­na­tion of human activ­i­ties and envi­ron­men­tal changes.

• Pol­lu­tion, par­tic­u­lar­ly plas­tic waste, is con­t­a­m­i­nat­ing marine ecosys­tems and harm­ing wildlife; it’s esti­mat­ed that 8 mil­lion met­ric tons of plas­tic enter the oceans annu­al­ly, lead­ing to dead­ly con­se­quences for marine ani­mals that ingest or become entan­gled in it.
• Over­fish­ing is deplet­ing fish pop­u­la­tions faster than they can replen­ish, dis­rupt­ing the bal­ance of marine ecosys­tems and threat­en­ing food secu­ri­ty for mil­lions who depend on seafood as a pri­ma­ry pro­tein source.
• Cli­mate change is caus­ing ocean tem­per­a­tures to rise and sea lev­els to increase, which con­tributes to coral bleach­ing and the loss of vital coastal habitats.
• Addi­tion­al­ly, the oceans are absorb­ing about 30% of the car­bon diox­ide emit­ted by human activ­i­ties, lead­ing to ocean acid­i­fi­ca­tion that affects shell-form­ing species and the broad­er marine food web.

These com­bined fac­tors high­light the urgent need for glob­al con­ser­va­tion efforts to pro­tect our oceans and ensure their health for future generations.

How can I help pro­tect our oceans?

To help pro­tect our ocean, you can:

1. Reduce plas­tic use: Use reusable bags, bot­tles, and straws to keep plas­tic out of the ocean.
2. Get involved in restora­tion: Get involved with restora­tion projects aimed at restor­ing ecosys­tems like man­groves for coastal pro­tec­tion or sea­grass for car­bon seques­tra­tion, help­ing to reduce ocean acid­i­fi­ca­tion. Check out your local coun­cil ini­tia­tives to get involved or explore DEW’s vol­un­teer­ing options.
3. Clean up: Join beach or riv­er clean-up events to remove rub­bish from waterways.
4. Save water: Use less water to reduce runoff that can car­ry pol­lu­tion to the ocean.
5. Learn and share: Edu­cate your­self about marine life and share what you learn with friends and fam­i­ly to raise aware­ness. Join a snor­kel­ing tour or become a cit­i­zen sci­en­tist.

Now you under­stand what all the comm-ocean is about, you can help keep our oceans healthy!

What is World Ocean Day?

World Ocean Day is cel­e­brat­ed on 8 June every year and brings togeth­er more than 2,000 organ­i­sa­tions from over 150 coun­tries every year to work togeth­er on con­ser­va­tion efforts. It’s a day to unite, cel­e­brate, and advo­cate for our oceans and a healthy climate.

Want to learn more about the unique marine life in South Australia’s waters? Take a look at sev­en of the most pop­u­lar marine crea­tures that live in SA’s waters.