Why Protecting Our SW Oceans Will Help in the Fight Against Climate Change

Marine Sanctuaries and Adaptation

  • Our oceans in WA are already suffering from mismanagement of fisheries, and large fish are in much smaller numbers.  Climate change will create another layer of damage and we need to ensure there is enough resilience in the system to withstand the impacts of climate change.  Sanctuaries have been shown to build resilience by restoring natural abundant populations of marine life.
  • Fisheries management is based on historical catches.  In Western Australia, anecdotal and scientific evidence shows that species are already moving south.  In a few years historical records of fishing will have much less meaning undermining any attempts at maintaining  a scientific basis for managing our fisheries unless we have sanctuaries as reference areas.
  • Climate change will mean more tropical species will start invading southern ecosystems.  This is in addition to the invasive species problems we already have from shipping.  Research on the Great Barrier Reef shows that crown-of-thorn outbreaks are less in sanctuaries, raising hope that the increased resilience of these areas will help ecosystems adapt to invasion.
  • Cold water ecosystems are expected to suffer the most from ocean acidification associated with climate change because cold water absorbs carbon quicker and becomes acidic more rapidly.  Creating marine sanctuaries to build the resilience required to fight the affects of ocean acidification is most urgent in colder waters like those surrounding southern Australia.

Marine Sanctuaries and Fighting Climate Change

  • Recent research has shown that whale poo acts as a fertiliser and whales are net carbon sequesters.  The research focused on Sperm Whales which feed at many deep water areas around South West WA.  Protecting their feeding grounds to support an abundant whale population can help the ocean’s ability to sequester industrial CO2 emissions.
  • A recent study has shown that when fish drink seawater they excrete calcium carbonate and thus sequester carbon into the ocean.  Conservative estimates are that 3-15% of ocean carbonates come from fish, but the number could be three times higher.  Documented abundance of large fish in sanctuaries (between two and fourteen times fished waters) would sequester significantly more carbon than fished waters.




Marine Sanctuaries Draw Tourists: Protect Millions in Assets

Dr Tod Jones, a leading researcher at Curtin University says that a network of marine sanctuaries off the South Coast of Western Australia would protect assets that generate millions in tourism revenue and protect the ‘clean, green, pristine’ brand of South West WA…

Full story via ABC here.

Company Loses Rottnest Oil Lease

A piece of good news today.  Rather than risk polluting Perth’s clean beaches and precious waters, the company who owns the large oil lease north of Rottnest Island has decided to ‘time-out’ on their lease under the ‘use-it-0r-lose-it’ provisions of the act.

The move opens up the possibility of taking away the oil lease for good, and thus making the biodiversity rich area on Perth’s doorstep a new marine park with large marine sanctuaries, that will help to protect Perth’s marine life from overfishing and future oil drilling, and restore the ailing fish stocks in the region.

Values of the region include Perth’s marine playground and A-Class Nature Reserve Rottnest Island, and the Perth Canyon – one of only three places in Australia where the blue whale feeds.

The pressure is now on the Government to do the right thing and make the area a marine park rather than putting the controversial lease back out to tender.

The first test will be on April 11th when the Government will announce the 2011 acreage release at the annual APPEA conference.  The second will be when the Government announces new marine parks for WA’s southwest region in late April.

The West Australian’s online coverage here.

If you want to join the campaign to protect Western Australia’s marine life hotspots, visit Save Our Marine Life at www.SaveOurMarineLife.org.au.

Protecting South Australia’s Marine Life

South Australia’s marine life is amongst the most unique in the world.  As part of the isolated southwest corner of Australia where up to 90% of marine life is unique to the region.  The waters off South Australia are home to 80% of the world population of Australian sea lions and critical breeding and feeding areas for many species of whales, including southern right whales and blue whales.

However, the State Government’s recent moves to establish a network of marine parks to protect this unique marine life have met with some vitriolic and hysterical opposition in regional South Australia led by the fishing industry lobby.  Whilst it is likely the reaction is skin deep across the general population (polling last year showed 75-80% support for an increase in marine protection), it has dominated media coverage in the state for the past month and threatens to undermine moves to protect marine life in the State.

Attacks are focused particularly on marine sanctuaries, or sanctuary zones, the fully protected parts of marine parks that bring the real conservation benefits.  Whilst these areas only cover a bare minimum 10% of South Australia’s waters, far less than levels recommended by scientists to reverse declines in our ocean biodiversity, the attacks have been blistering.

Despite evidence from elsewhere in Australia – like the highly successful leading marine parks at the Great Barrier Reef and Ningaloo Reef that have driven economic diversity and growth whilst also protecting the environment – opponents from South Australia’s well funded fishing lobby groups have attacked the sanctuaries on everything from their science basis, to ruining regional economies, to devastating housing prices, to even risking the lives of fishermen.

Despite there being no evidence to back up these increasingly extraordinary claims, the attacks have overwhelmed media coverage, with the strong science case and environmentalists having little opportunity to respond to the tide of increasingly exaggerated claims.

However, now The Wilderness Society South Australia is fighting back and reviving the two year campaign that got the Government to the point of declaring the draft park maps in the first place.  They will need all the help they can get, so please sign up to their campaign online and petition SA Australia’s Environment Minister and Premier to stick to their guns and do the right thing by establishing a network of sanctuary zones to protect South Australia’s unique marine life.

For more information on the benefits and need for marine sanctuaries, see previous blog post “What is a  marine sanctuary, and do they work?”.


Shell drilling proposal threatens Ningaloo Reef

See coverage in the Australian here, Shell now planning to drill on the ocean side of world heritage nominated Ningaloo Reef.

Adds to the threat of drilling in the Exmouth Gulf, on the mainland side of the Ningaloo Reef peninsula, see more about that in previous blog here.

With 25% of WA’s waters already in oil and gas leases, and petroleum looking to be a boom industry for the state, we really need to get our act together to ensure our high value natural places are protected from the expansion of this industry.  Places like Ningaloo Reef.

A spill here would be a disaster for the local economy and environment, and the world – with the reef now nominated as a world heritage site.

Does Recreational Fishing Impact Fish Stocks and the Environment?

Another big question that has been posed in the debate over new marine parks around Australia is: does recreational (or amatuer) fishing really have an impact on marine life and fish stocks?  Or in personal terms, how could little old me with my rod and line impact the vast big blue ocean?

Its a fair question, and unfortunately, the answer is yes.  The metaphor ‘death by a thousand cuts’, or in this a few hundred thousand, applies.   In WA alone, there are more than 100,000 boats, many of which are used for fishing.  Many thousands more people fish from shore.  Thats a lot of cuts.

So thats the short answer, but what is the evidence? That is best answered in two separate ways:

  • Whats the evidence of recreational fishing taking enough fish to impact the marine environment and fish stocks?
  • Whats the evidence that removing recreational fishing  in marine reserves benefits marine life and fish stocks?

The first question is hardest to answer because so little research has been done on the impacts of recreational fishing.  The amount of fish taken by recreational fishers is very hard to predict or measure as there are no formal reporting mechanisms, so managers rely on surveys and/or modelling.  Also, because it hasn’t traditionally been perceived as a potential problem for marine life and fisheries, very little serious research has been done.

However, in WA the most researched, and threatened, fish are the demersal reef fish, and in particular the Western Australian Dhufish.  Estimates in 2005/2006 show recreational fishers took 319t of fish compared to  commercial fishers who took 163.9t – meaning recfishers took 66.1% of the catch.

These species are typically long living and slow breeding, the kings of the reef, making them highly susceptible to overfishing.  Big old ‘trophy’ fish also tend to be the best breeders – a one metre female dhufish will produce as many eggs as eleven fish half her size.

The Government has halved commercial take of dhufish, and is now seeking to halve the recreational take through a series of measures, which shows up another problem.  You can reduce the take of a commercial fleet (excluding bycatch issues with some fishing methods such as trawling or gillnetting) by applying quotas or effort restrictions.  But it is much much harder to reduce the number of fish taken by thousands of recreational fishers all along the coast.

WA’s state recreational fishing lobby group Recfishwest is now negotiating with the Fisheries Department for recfishers to be allocated around half the catch of demersal reef fish on the west coast, which will be a 50% reduction in the current estimated recreational fishing take.  There is a draft of the recfishwest submission on this at the Fishwrecked forum here.

With all these measures in place, evidence still suggests the take of dhufish is still too high.  Time will tell, but this is increasingly a threatened species.

Its not just WA. Similar circumstances are occurring with snapper in SE Queensland where the Fisheries Department is moving to reduce recreational fishing take through seasonal closures.

NSW isn’t having to deal with harsh fishing restrictions at the moment, but figures for NSW recreational vs commercial take below show that recreational fishing is a major contributor to take of a number of species in NSW too:

Annual Tonnes 


Commercial catch Recreational catch 


Dusky Flathead 120 570-830 


Mahi Mahi <5 100 


Mulloway 40 100-500 


Yellowfin Bream 360 820-1070 


Bluespotted flathead 125 320-450 


(Source: NSW Department of Primary Industries Status of Fisheries Resources 2006/2007)

Given these figures it is clear that  both commercial and recreational fishing is having an impact.  So taken as a total picture, the answer is yes, people with a rod and reel are impacting fish stocks and the marine environment.

So what about removing recreational fishing from marine reserves?  Is this necessary, and will this really make any difference?

In this area there is much more clear evidence because there has been much more study of the effects of different types of marine parks.  I will share the very best example I have seen to illustrate this from the very well studied Poor Knights Islands marine reserve in NZ.

The area was closed to commercial fishing in 1981, but by 1998 it was clear there weren’t significant benefits for protecting snapper populations and the reserve was made a fully protected marine sanctuary.  You can see from the graph what then happened.  The red dots are snapper numbers in the Poor Knights Marine Reserve, and the green is snapper numbers in nearby reference sites.  As the graph shows, numbers of legal sized snapper increased to 14 times their previous abundance in just half a decade.

Perhaps more exciting for fishermen, you can also see a seasonal variation in snapper numbers.  This means some large fish are migrating out to surrounding waters where they are accessible to fishermen. The marine sanctuary is providing environmental benefits by protecting large fish, and also acting as an ‘engine room’ for local fishing.

Graph of snapper recovery in Poor Knights Island marine sanctuary

The environmental impact of this depletion of large fish is also fascinating.  In NZ again, after decades of coastal overfishing large areas of coastal waters were in areas called ‘urchin barrens’, where sea urchins had thrived and reduce the cover of kelp over the rocks.  This was thought normal until marine sanctuaries were established.  Within a few years, renewed populations of large snapper and crayfish had eaten many of these urchins, allowing the kelp to regrow and increasing the productivity of these coastal waters.

It was even observed than large lobsters actually changed their physical structure at a certain size to better break open urchins, something that had not been observed in NZ before the sanctuaries were put in place.

A similar result was seen on the Great Barrier Reef where crown of thorn starfish outbreaks were reduced in green zones.

So the answer is yes, recreational fishing does impact fish stocks and the marine environment, and yes, creating sanctuaries protected from all fishing is necessary to protect marine life – and it can also improve fishing.

However, for my recfishing friends, I’d like to emphasize that this doesn’t make recfishing bad.  All it means is that recfishers who care about the marine environment and future of fishing should be as supportive of marine sanctuaries as the greenies who care about marine life.  Done right, they are a win-win for all ocean users.

I’ll keep working on this important topic and post any further research and information I can find.

If you have anything interesting, leave a comment or email me at onehappyfish@gmail.com.

For more on marine sanctuaries and the environment/fishing/economy, see my previous ‘post of the month’: What is a marine sanctuary and do they work?