fisheries – Page 7 – ANGFA Queensland

Fish fears rise over LNG port dredging

community, fisheries, government, waterways/wetlands

Nov 192013

AN outbreak of diseased fish in Gladstone Harbour coincided with a toxic algal bloom that may have been fed by a leaking rock wall used to contain dredge spoils from the $33 billion Curtis Island LNG projects.

Dead fish in Gladstone Harbour. Photo: Gladstone Conservation Council

Gladstone Ports Corporation has known about the algal bloom and increased sediment from its infrastructure works for more than two years but only in recent weeks has it made the reports publicly available.

It said it still believed that heavy flooding was the primary cause of the outbreak of fish disease in 2011, as established by a scientific review.

However, the just-published 2011 report says it is "possible that harmful algal blooms may have been a possible contributing factor in the fish disease syndrome".

Veterinarian Matt Landos, who has investigated fish health in Gladstone, said the newly published material provided a convincing alternative point of view.

"Scientists can only work with the data which is provided to them," Dr Landos said.

"The full data now seriously contradicts the conclusions of the state and commonwealth that floods were to blame.

"Given the serious nature of the 'new' information that is now in the public realm, another independent review of the science around causes of Gladstone ecosystem crisis seems warranted, in addition to an inquiry into the decision-making around information control during the project."

The head of the scientific panel for the state's review, Ian Poiner, confirmed that the algae reports were not available at the time of its review into fish health and said he had not studied them in detail to determine whether they contradicted the official finding that the marine-health issues were related to flooding.

Dr Poiner is now chairman of Queensland government's Gladstone Healthy Harbour Panel.

A spokeswoman for GPC, whose dredging project is essential for the development of the Curtis Island liquefied natural gas plant, said the reports were made available to the federal government's independent review panel, which was requested by UNESCO.

The Weekend Australian revealed plans by GPC to dump 12 million cubit metres of dredge spoils into the Great Barrier Reef World Heritage Area have been blocked by Canberra. The spoils from the dredging of a second sea lane will now be used to reclaim land in Gladstone Harbour.

GPC has previously conceded environmental problems caused by a "leaking" bund wall designed to contain dredge spoils.

Gladstone Harbour was closed to fishing in September 2011, following reports from commercial fishermen in August that many fish were showing signs of disease. The ban was lifted but commercial fishermen continued to report high numbers of turtle, dugong and dolphin deaths.

GPC said it commissioned the special water-quality report in October 2011 after higher turbidity readings were recorded during this period, "due to extreme tidal movements, high wind conditions and the porosity of the bund wall".

The report finds "highly turbid waters were most likely created in September/October 2011 due to the addition of fine sediments derived from the overly porous bund wall and dredge-related operations".

It said organic matter comprised a large proportion of the total suspended sediments measured in October 2011, suggesting an algal bloom, particularly in the Western Basin area of the harbour. "Several potential harmful algal species were identified, which have previously been associated with fish kills."

An analysis of the algal bloom by Larelle Fabbro, from Central Queensland University, found three algal types, including Chaetoceros, had previously been associated with fish kills.

"There is scientific evidence that concentrations of Chaetoceros of more than five cells per millilitre can kill fish," Associate Professor Fabbro writes in her report. She says "concentrations of Chaetoceros were as high as 300 cells per millilitre in a sample taken on 12 October, 2011".

"The spines of this diatom spear into the gills and can result in significant damage," the report says.

"The sequence of injury is by initial penetration of the silica spines into the fish gills, capillary bleeding or the production of excessive quantities of mucus leading to death by suffocation."

Associate Professor Fabbro told The Australian it was a condition of her research that she not make any public comment.

But the 2011 report says "the finding of potentially toxic algal species was also of note in light of the fish disease syndrome which was being concurrently investigated in Port Curtis".

"A number of fish, particularly barramundi, had previously been presented in Port Curtis with lesions, rashes and excess mucous production with the syndrome being the focus of a separate independent investigation," it says. "Therefore it is possible that harmful algal blooms may have been a possible contributing factor in the fish disease syndrome."

GPC has confirmed that the water quality reports for September and October 2011 were not made publicly available until September this year.

But it said all relevant reports had been made to all government departments and relevant agencies.

It said the key finding was that research indicates an algal bloom was present in August 2011 prior to the start of dredging with the cutter-section dredge.

"Several potential harmful algal species were identified, which had been previously associated with fish kills," it said. "The algal species identified were not uncommon for the Port Curtis area, for that time of year."

It said an independent panel had concluded that, based on all data available, the most likely cause of fish health issues were flood-related.

Australia’s aquaculture sector expanding

aquarium, fisheries, government

Nov 182013

Australian Fisheries Statistics 2012

Original story at Enviroinfo

Australia’s aquaculture industry now accounts for almost half of the nation’s fish production.

The Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES) Australian fisheries statistics 2012 annual report shows aquaculture has increased its share of fishery product earnings from 30 per cent to 46 per cent over the last decade.

Parliamentary Secretary for Agriculture, Richard Colbeck, said most of the increase could be attributed to the fast-growing farmed fish sector.

“Farmed salmonids became the largest species group produced and increased earnings by 20 per cent in 2011-12. It remains Australia’s highest earning fisheries product at a value of $513 million.”

Senator Colbeck said the growth in the aquaculture industry vindicated the government’s plan to work with industry to develop a national aquaculture strategy.

“We want to further develop the aquaculture industry in Australia because there are huge opportunities to be had.

“The fisheries sector is vital to regional economies and the tens of thousands of people employed in the industry. Our national aquaculture strategy will create employment in regional areas and support the sector so it continues to grow into the future.”

Senator Colbeck said the report showed the total gross value of production of Australian fisheries increased three per cent to reach $2.3 billion.

‘Saving our Fish’ needs more than a ban on discarding

fisheries

Nov 132013

Media release from the University of East Anglia.

Banning the practice of throwing unmarketable or over-quota fish back into the sea is just one of the measures needed to deliver sustainable fisheries according to new research from the University of East Anglia.

Photo: Hans-Petter Fjeld

Research carried out by UEA with the Centre for Environment, Fisheries and Aquaculture Science (Cefas) and published today in the journal Fisheries Research reveals that a ban will only help future fish stocks if it is accompanied by other measures to reduce total fishing mortality.

Approximately half of the fish caught in marine fisheries are thrown back into the sea, but very few survive. The practice has bedevilled politicians, fisheries managers, scientists and fishermen for many years.

The move to ban discarding has gained widespread public support through the campaigning efforts of supermarkets, pressure groups, chefs including Hugh Fearnley-Whittingstall, and other celebrities such as the band Coldplay and the comedian Ricky Gervais. The new European Common Fisheries Policy (CFP) which is expected to enter into force in 2014 intends to ban the wasteful practice for all quota stocks by 2019.

The research team combined information on landings by English trawlers in the North Sea with data on discards collected by onboard observers. They then used this data to assess how a discard ban will impact the catches and profits of different segments of the fleet.

Key findings:

- A discard ban alone may not reduce unwanted catches.
- A ban in isolation does not create a strong incentive for selective fishing.
- Catch quotas (where all fish caught are counted against a limit) create strong incentives to avoid regulated species, but not other species.
- Profits of some parts of the fleet may be hit unless catch quotas are set differentially.
- Vessels catching the least fish may see the largest profit declines under catch quotas.

Lead researcher Harriet Condie, from UEA’s school of Environmental Sciences, said: “We took into account data such as catch and discard figures from fishing trawlers, fish prices and landing costs, to calculate whether banning the practice of discarding will offer enough of an economic incentive to fish sustainably.

“The most important measure to safe-guard over-exploited fish stocks is to reduce the number of individuals being caught. But our research shows that a discard ban in isolation may not result in a dramatic reduction in unmarketable catches of all species.

“If all fish have to be landed, we will get better information on exactly how many fish of each species are being caught and the state of fish stocks. But the fact that fish can no longer be thrown back into the sea will not automatically make their exploitation any more sustainable because we show that there is no significant incentive to avoid catching them.

“We went on to investigate whether a discard ban in conjunction with different management scenarios would work – such as reducing fishing effort and limiting the amount of fish that can be landed.

“We found that a ban combined with catch quotas has the greatest potential to incentivise more selective fishing, but only for regulated species such as cod, haddock and plaice.

“Experience from elsewhere in the world shows that discard bans are only effective if they are enforced by high levels of surveillance or there are economic benefits from landing fish that are currently discarded. But neither of these options is straightforward as policing fisheries is expensive and economic incentives can encourage increased catches of unwanted fish,” she added.

Prof Alastair Grant, who supervised the work, said: “As welcome as the public’s awareness about discarding may be, our research shows that a move towards the sustainable management of European fish stocks will require more than just a discard ban as the landing of all fish does not itself make exploitation more sustainable.

“A fish that is landed and turned into fishmeal makes as little contribution to future generations as one that is thrown back into the sea dead. The biggest challenge is to reduce fishing mortality, and national and international politics have always made that politically difficult to achieve.”

Thomas Catchpole from Cefas said: “Choosing the right measures can be complicated and sufficient time is required to allow fishermen to adjust to a new management approach.

“The recently agreed reforms to the Common Fisheries Policy took years to secure but the policy now includes a phased introduction of a discard ban (completed by 2019) and legally binding commitments to set quotas at levels that achieve maximum sustainable yields of commercial fish stocks. In the interim governments have funded research to quantify and redress the impact of discarding. Catch-quota trials have been funded as have projects to design and use more selective fishing nets.

“A catch quota system provides the potential to remove many of the technical regulations currently in place, which will give fishermen increased flexibility in how they operate their businesses. This will be helped by decentralising the management of European fisheries and using a more regional approach, which was another agreed aspect of the reformed CFP.”

‘Does banning discards in an otter trawler fishery create incentives for more selective fishing?’ by Harriet M, Condie, Alastair Grant, and Thomas L. Catchpole, is published in the journal Fisheries Research on November 11, 2013. The research was funded by the Department for Food and Rural Affairs (Defra).

Warmer waters lure sub-tropical fish to the south

environment, fisheries, waterways/wetlands

Nov 112013

Original story by Sarah Taillier, ABC News

As ocean temperatures rise off Western Australia, sub-tropical fish are swimming south and many are staying there.

Researchers are finding new fish species, such as the the roundface batfish, off the WA coast. Photo: Redmap.org.au

Gary Jackson, the principal research scientist with the Department of Fisheries, has been monitoring changes in fish distribution off the state's coast.

"We're definitely seeing warming of the waters off the west coast and marine creatures, including fish, are taking advantage of this and actually moving basically southwards," he said.

"We've got a whole portfolio of reports coming through in the last two to three years of some pretty unusual fish occurring south of Geraldton, off Perth and as far around as the Capes on the south coast.

"So strange things are happening and we're only really starting to scratch the surface now on what is going on."

The southern migration of fish and marine creatures is driven by two main factors; a gradual increase in ocean temperatures and the effects of the Leeuwin Current which Dr Jackson describes as a type of "fish highway."

He says when that current, which runs southwards along the entire coast of WA, flows strongly, a lot of marine life moves with it.

"Small fish actually get pushed along by that strong current and larger fish basically get on it and it's easier swimming for them and they'll really go where that plume of warm water takes them," he said.

Craig White runs a charter boat business out of Jurien Bay and has been fishing in waters off the Mid West coast of WA for about 25 years.

The offshore world champion angler says since a marine heatwave moved through the area in late 2010 and into early 2011, he has noticed new fish species moving in.

He says now there are signs those fish are prospering.

"They've actually become prolific, they're absolutely everywhere, there's been a massive influx of them."

Craig White

"After that (marine heatwave) happened we could get red throat snapper in a few very isolated areas and quite a random catch whereas up in Leeman you could get quite a lot of them and in Jurien Bay very few," he said.

"Now we can get them from the back of the reef all the way out.

"They've actually become prolific, they're absolutely everywhere, there's been a massive influx of them."

Heatwave results in coral bleaching and fish kills

During the marine heatwave in 2010/2011, ocean temperatures between Kalbarri and Jurien Bay rose by up to five degrees, resulting in coral bleaching, and fish and invertebrate kills in an area considered to be a global biodiversity hotspot.

Marine ecosystems within the area are still recovering from the damaging effects of what is referred to as an "unprecedented extreme warming event."

Ming Feng is a physical oceanographer and principal research scientist with CSIRO who leads the Integrated Marine Observing System, IMOS, which monitors the long term changes in the Leeuwin Current and the impact of climate change in WA.

Dr Feng says over the last 60 years, ocean temperatures off the west coast of Australia have warmed by up to one degree.

He says ocean temperatures off the state's coast are expected to continue to rise which means the frequency and severity of ocean heatwaves are likely to intensify.

"So with the warming temperature tend, any future marine heatwave event will be superimposed on that slow rising trend," he said.

"So if you have the same threshold for marine biota the marine heatwave you experience in the future will have a much higher anomalies than probably 20 or 30 years ago."

Temperature anomalies at the peak of the Ningaloo Nino. A map showing temperature anomalies at the peak of the marine heatwave. Image: CSIRO

Dr Feng says ocean temperatures off WA are generally determined by the strength of the Leeuwin Current which is influenced by the tropical Pacific climate.

He says climate forecast models for the next few months predict a neutral condition for the tropical Pacific climate.

"So if the tropical Pacific climate is neutral in the coming summer, then it's very unlikely we will experience another extreme marine heatwave off the WA coast," he said.

Dr Feng says although extreme marine heatwaves are unlikely over the next few months, other less severe temperature events may occur.

"Marine heatwaves can be triggered by other variabilities of the local winds in the Indian Ocean off this coast but these type of marine heatwaves or temperature anomalies tend to be more moderate," he said.

He says another extreme heatwave would have a damaging effect on marine environments, especially for ecosystems in areas off WA which are expected to take years to recover from the last extreme heat event in 2010/11.

Sub-tropical fish taking up residence in southern waters

Dr Jackson says certain fish are taking advantage of the warming ocean temperatures.

"Warm water or sub-tropical species have a certain temperature range," he said.

"And, if those temperature ranges are found a bit further south of where they typically are, then those animals will quite happily move there, live there and stay there, if those conditions are right and obviously if they can find food," he said.

It appears the conditions are right in many areas as Dr Jackson says fish are changing locations and remaining there.

"They seem to have stayed, survived through the winter - which is normally the telling thing if they can survive through the cooler temperatures - and some of those fish appear to be basically breeding in the region now," he said.

Meanwhile, Mr White says the warming oceans temperatures have brought benefits.

"I personally think it's a good thing, we're getting a lot more species of fish, a lot more variety, and it doesn't appear to be bothering the local stocks," he said.

"That's coming from a typical fisherman's point of view.

"There's a saying going around that 'global warming means rising sea levels…more fishing spots'."

If you've seen any unusual fish or marine life in your area, scientists are asking you to take a photo and upload it to Redmap (<http://www.redmap.org.au/> - a national, citizen science project tracking the changing distribution of marine species.

Barra off limits

fisheries, government

Nov 102013

Media release from DAFF

Fishers are being reminded that barramundi will be off limits in the Gulf of Carpentaria from noon 7 October 2013 until noon 1 February 2014.

Queensland Boating and Fisheries Patrol district officer Owen Witt said the closure was in place to protect barramundi stock during their vulnerable spawning season.

"Barramundi typically aggregate in one area to spawn, making them more vulnerable to predators and fishing pressure,” he said.

“Closed seasons allow stocks to replenish to ensure there are healthy fish stores for current and future generations of Queensland anglers,” he said.

A barramundi closure will also apply in East Coast waters from midday 1 November 2013 to midday 1 February 2014.

For more information on closed seasons for fishing in Queensland, visit www.fisheries.qld.gov.auor call 13 25 23.

Follow Fisheries Queensland on Facebook and Twitter (@FisheriesQld).

Media contact: Jodana Anglesey, 3087 8601

Prawn trawlers accused of large fish kills

fisheries, threatened species, waterways/wetlands

Nov 092013

Original story by Carl Curtain, ABC Rural

Recreational fishermen in the Northern Territory are venting concern over recent fish kills, which they say are being caused by prawn trawlers.

Recreational fishermen in the Northern Territory are venting concern over recent fish kills. Fish apparently found floating in the Gulf of Carpentaria.

The Nhulunbuy Fishing Club, on the north east Arnhem Land coast, has received photos of small trevally and mackerel which were apparently found on floating in the ocean.

The NT Game Fishing Association executive officer, Peter Cox, told ABC Local Radio the dead fish are the by-catch from trawlers operating nearby.

"Our concern is how close they're working to some of our reefs and seagrass patches, especially with dugong and turtles.

"It's the by-catch. We have photos of just acres of dead fish floating on the water after the trawlers have been through," he said.

There are 52 prawn trawlers operating in the Northern Prawn Fishery, with the season running from August 1 through until November 30.

Austral Fisheries general manager, Andrew Prendergast, says he's surprised to hear about large fish kills.

"I'm not so much [surprised] about what they're claiming they saw, but the fact that they believe we're trawling on top of reefs, which we simply can't do.

"We've got closures all around the fishery to protect our seagrass beds because that's where our tiger prawns breed," he said.

"It would be commercial suicide for us to go near seagrass beds."

He says prawn trawlers use mechanical devices to prevent the netting of large fish and turtles, which also reduce the by-catch.

"There is a 100 per cent compliance with the towing of these devices in the nets, you simply cannot go to work without them.

"We tend to get a very good relationship between by-catch and the prawn during the night part of our trawl," he said.

"All fishermen do their best to avoid [a fish kill], but if they've trawled through until eight o'clock in the morning, they may have encountered a small patch of fish which, as they've discarded it from the catch, has floated on the surface."

High Court casts a line on right to fish

community, fisheries, government

Nov 072013

Originalstory by Mark Schliebs, The Australian

THE right of Aborigines to take any fish caught for traditional purposes from waterways and oceans has been confirmed after the High Court yesterday handed a father and son victory in a four-year legal battle, ruling that native title meant state fishery laws did not apply to them.

Narrunga man Owen Karpany at West Beach in Adelaide yesterday after the High Court upheld his right to fish on the Yorke Peninsula. Photo: Kelly Barnes, The Australian

The Aboriginal men had been embroiled in a legal fight with South Australia's Labor government since 2009, when they caught 24 undersized abalone at Cape Elizabeth on the Yorke Peninsula. In a unanimous decision yesterday, the High Court ruled that South Australian fishing laws enacted in 1971 did not extinguish native title rights as the government had argued and found the Narrunga men had done nothing wrong by keeping their catch.

At least two other states and the federal government have unsuccessfully argued that laws restricting the killing of fauna have extinguished native title.

The High Court ruled in August that federal and Queensland laws did not extinguish the native title right of Torres Strait Island communities to fish commercially without a licence.

In what was seen as a national precedent, Aboriginal man Murrandoo Yanner won a High Court battle with the Queensland government in 1999 after using a traditional form of harpoon to catch two juvenile crocodiles in the Gulf of Carpentaria five years earlier, despite state laws against the hunting of the young reptiles.

In yesterday's ruling, South Australia's Attorney-General John Rau was ordered to pay legal costs to the two men, estimated to be more than $400,000.

Owen Karpany and his son Daniel, 26, were charged by authorities with taking the abalone in their native title area at Cape Elizabeth, southwest of Moonta on the Yorke Peninsula, northwest of Adelaide. "I didn't expect it to go as far as it went, but it went to the highest court in all of Australia with an outcome in my favour," said Mr Karpany, 61.

He said other native title holders were "over the moon".

"I did have my doubters, but I just stuck to my guns," he said.

"I knew that I was right from the beginning."

The Magistrates Court had originally ruled the men could not be punished over the abalone as they had been exercising their native title rights, but the government appealed the case to the full bench of the Supreme Court.

The Supreme Court last year ruled that native title fishing rights across the state were extinguished with the introduction of the 1971 Fisheries Act, which was replaced by the Fisheries Management Act in 2007. Yesterday, the High Court overruled that finding.

"The (legislation) did not prohibit or restrict the applicants, as native title holders, from gathering or fishing for abalone in the waters concerned where they did so for the purpose of satisfying their personal, domestic or non-commercial communal needs and in exercise or enjoyment of their native title rights and interests," the High Court ruled.

"The conceded native title right of the applicants was therefore a right to take fish from the relevant waters. That right comprehended the taking of abalone, including undersize abalone."

Perth barrister Greg McIntyre SC, a member of the Law Council of Australia's native title working group, said the ruling built on the August decision that fisheries laws could not override native title.

He said although the rulings would not have a direct impact on other states' fisheries laws, a principle on native title rights had been set by the court.

Andrew Beckworth, a lawyer from South Australian Native Title Services, who assisted the men, said the four-year battle had cost the government, which was always unlikely to win, hundreds of thousands of dollars. "More than anything, we were just bewildered that our state government persisted with this argument," he said. "We're not sure what they were trying to achieve."

Mr Rau has sought advice from the crown solicitor on the impact of the ruling, but said he did not fear widespread taking of under-sized fish.

Nations discuss fresh bid to create world’s largest marine park

fisheries, government, waterways/wetlands

Oct 252013

Original story by Tyson Shine, ABC News

The future of what would be the world's largest marine reserve could be decided at a meeting in Hobart this week.

A large iceberg in Antarctic waters, photographed from the Aurora Australis in January 2011. The CCAMLR meeting will again consider a push to protect 1.6 million square kilometres around East Antarctica. Photo: Emma Carlos

A fresh bid to have areas of the ocean off East Antarctica and a revised protection plan for the Ross Sea are being discussed by the Conservation of Antarctic Marine Living Resources (CCAMLR).

Hundreds of scientists began discussions on Monday and delegates will begin their meeting tomorrow.

Two main proposals will be considered.

High on the agenda is a proposal to create a series of marine protected areas off East Antarctica, covering 1.6 million square kilometres.

It would effectively ban fishing in the last pristine marine environment on earth.

Australia, France and the European Union are pushing for the change and most of CCAMLR's 25 members support it, but Russia's position is unclear.

Another proposed protected zone for the Ross Sea, jointly suggested by the US and New Zealand, has been reduced by 40 per cent, after Russia and the Ukraine blocked the plan at CCAMLR's last meeting in Germany in July.

Russia holds lucrative fishing licences in the area and raised legal objections.

If the new bid succeeds it would result in the protection of 1.25 million square kilometres.

What is CCAMLR?

A group of 25 bodies (24 nations and the EU)

Established by international convention in 1982 to conserve Antarctic marine life.

Set up in response to increasing commercial interest in Antarctic krill resources.

Secretariat based in Hobart, Australia.

It is understood Norway will now support the creation of the protected areas after holding initial reservations about the zones' impact on its fishing industry.

Conservationists lobbying for the park are being led by the Antarctic Ocean Alliance.

Spokesman Steven Campbell says it is important to protect the areas "while its key ocean ecosystems are still intact."

The countries that make up CCAMLR need to show real leadership to deliver on their commitments to establish a network of [Marine Protected Areas] on Antarctica," he said.

The alliance will attend the meetings to try to convince member nations to back the proposal.

The results of the meeting are not expected to be known until the meeting winds up in two weeks.

The ocean is not broken, but consumer behaviour is

environment, fisheries, threatened species, waterways/wetlands, wildlife

Oct 232013

Original story by Carlos Duarte, University of Western Australia at The Conversation

In an emotional article making waves on social media at the moment, yachtsman Ivan Macfadyen reports seeing no marine life at sea, only floating rubbish, while sailing across the Pacific. He concludes that “the ocean is broken”.

A tide of tsunami debris is heading across the ocean - that doesn’t mean the ocean is broken. Photo: US Navy

I understand Ivan’s feelings, as I too have sailed tens of thousands of miles onboard research vessels and on my sailboat, enjoying the slow and silent pace of life propelled by wind and waves.

The two issues Macfadyen raises - overfishing and plastic pollution - are real problems. More than three-quarters of the oceans' fish stocks have been depleted, sometimes beyond recovery. The global tuna industry, particularly, is better portrayed as the War On Tuna than a fishery. And the world’s oceans are filled with large amounts of plastic debris, which are eaten or caught up in marine life or seabirds, or which break down into microscopic particles that are ingested and affect wildlife in ways we don’t yet know.

So yes, there are plenty of problems in the ocean. But it is not yet broken. I am increasingly upset about reports that say it is; we scientists are to some extent to blame, as we love being the bearer of bad news, composing an overly apocalyptic narrative.

Depicting the ocean as broken and suffering from a litany of plagues including climate change, hypoxia, eutrophication, ocean acidification, marine pests, spreading jellyfish blooms, and loss of valuable habitat, suggests a problem beyond repair. This eventually deters society from engaging. These plagues are certainly real, but their severity is sometimes exaggerated through a feedback loop involving, among others, the spinning of research headlines to compete for media attention.

The ocean has many problems - plastic debris among them - but is a long way from “broken”. Photo: USFWS

Let’s focus on Macfadyen’s evidence for a broken ocean: two snapshots of the Pacific, ten years apart, suggesting a depletion of marine life and huge plastic pollution.

The ocean is a dynamic ecosystem, which fluctuates broadly over time, from its physical and chemical properties to the abundance and distribution of fauna and flora. Such fluctuations can deceive the casual observer - to detect real change requires high quality data gleaned from systematic long term observations.

For instance, my co-workers and I analysed global changes in jellyfish populations, and found there is no basis to the claim that they are growing “plague”. Instead, we found that jellyfish populations fluctuated over 20 year cycles, giving the misleading perception that the most recent rising phase of this cycle (roughly between late 1990s and late 2000s) was an unprecedented event.

Likewise, we also know that many changes portrayed as symptoms of a broken ocean, such as coral bleaching, outbreaks of invaders such as the crown of thorns starfish or toxic algae, may also largely represent symptoms of global oscillations that we do not yet fully understand and in which humans' actions play little or no role. Separating the human impacts entwined in such natural fluctuations is a daunting task, so we should not be too quick to jump to conclusions and blame humans for all the changes we see around us. Our analysis showed that such fluctuations happened in the past, but very few scientists were watching and they lacked the channels, such as the internet, to share their results.

Soon after the earthquake and tsunami of March 2011 that triggered the Fukushima accident, NOAA published models that predicted how the huge amount of debris washed into the ocean by the power of the retreating waves would take three years to travel across the ocean and wash up sometime in 2014 on the beaches of California, Oregon and Washington in the US. Had Macfadyen checked NOAA’s web page, he’d have expected the garbage patch he encountered.

The tsunami was not caused by humans, so we should rein in our feelings of guilt about it. It does, however, provide a brutal exposure to the reality that we feverishly consume and dispose of too many, mostly plastic objects, many manufactured with harmful chemicals, that we use just for just a short while and then throw away.

What kind of fishing line did Macfadyen use in his first voyage, and what happened to it when he’d finished? What chemicals are in the anti-fouling paint for his boat’s hull? Likewise, how and where was the fish we consumed with our last meal captured? Did it come from a sustainable fishery or a sustainable aquaculture farm? Did we bother to ask if it was a certified product? Do we demand that this information be displayed to guide our choices as consumers?

Should we eat tuna, an apex predator at the top of the food chain, or should we settle for sardines, oysters and seaweed? Was that chicken we ate yesterday for dinner fed fishmeal? Do we drive a four-wheel drive car whose CO₂ emissions will further acidify the oceans, or do we cycle, drive a hybrid or electric vehicle or catch a bus powered by biofuels? Do rich, developed nations with among the world’s largest greenhouse gas footprints refuse to implement carbon taxes or emissions reduction strategies because we “cannot afford” them?

These questions are not easy ones to ask ourselves, but we confront our contradictions. We enjoy eating seafood, an essential component of a healthy diet. We know that fish stocks are over exploited, so developing aquaculture is the only avenue to sustainably meet the growing demands for seafood. But then we get upset if we can see an aquaculture farm off our coasts.

Responsible consumers will not break the ocean; those who choose to ignore the consequences of their day-to-day decisions as consumers will. The place where the struggle to save the oceans from breaking is fought everyday - not once every ten years - is at our local shops.

Carlos Duarte receives research funding from The EU Framework Program, the Spanish National Research Plan and the CSIRO, and he is affiliated with the Spanish National Council for Scientific Research (CSIC) and The University of Western Australia.

This article was originally published at The Conversation.
Read the original article.

Tiny sea creatures heading for extinction could take fisheries with them

environment, fisheries, threatened species, waterways/wetlands

Oct 212013

News release from Deakin University

Calanoid copepods are a plankton species that are a vital food source for fish larvae and therefore important for all commercial fisheries. Photo: Paul Jones, Deakin University.

A species of one of the world’s tiniest creatures, ocean plankton, is heading for extinction as it struggles to adapt to changes in sea temperature. And it may take local fisheries with it.

Research led by Deakin University (Warrnambool, Australia) and Swansea University (UK) has found that a species of cold water plankton in the North Atlantic, that is a vital food source for fish such as cod and hake, is in decline as the oceans warm. This will put pressure on the fisheries that rely on abundant supplies of these fish.

“There is overwhelming evidence that the oceans are warming and it will be the response of animals and plants to this warming that will shape how the oceans look in future years and the nature of global fisheries,” explained Deakin’s professor of marine science, Graeme Hays.

“We know that warm water species are expanding their ranges as warming occurs, and vice versa. What is not known is whether species are able to adapt to new temperatures. Will, for example, cold water species gradually adapt so they can withstand warming seas and not continually contract their ranges. From the results of our study, it is looking like the answer is no.”

Answering the question of adaptation is not easy as it requires long-term observations spanning multiple generations. For this study, the research team examined a 50-year time series from the North Atlantic on the distribution and abundance of two very common but contrasting species of ocean plankton, Calanus helgolandicus that lives in warmer water and Calanus finmarchicus that lives in cold water. These crustaceans are vital food for fish and underpin many commercial fisheries in the North Atlantic region.

The researchers were surprised to find that the cold waterC. finmarchicus has continued to contract its range over 50 years of warming.

“In other words, even over 50 generations (each plankton lives for one year or less) there is no evidence of adaptation to the warmer water,” Professor Hays said.

“The consequences of this study are profound. It suggests that cold water plankton will continue to become scarcer as their ranges contract to the poles, and ultimately disappear. So certainly for these animals, thermal adaptation appears unlikely to limit the impact of climate change.

“C. finmarchicus is a key food source for fish such as cod and hake. So continued declines in abundance will have a negative impact on the long-term viability of cold water fisheries in the North Sea and other areas in the southern part of their range. At the same time the continued increase in abundance of the warm water plankton, C. helgolandicus, will likely play a role in the emergence of new fisheries for warm water species.”

Professor Hays said that the impact of ocean warming was not confined to the North Atlantic region.

“Ocean warming is occurring globally and so these findings are likely to apply to other areas around the world including southern hemisphere locations such as Australia, South Africa and South America that support important fisheries dependant on plankton,” Professor Hays said.

“Plankton recorders deployed in the southern hemisphere, for example as part of the Australian Continuous Plankton Recorder Project (a joint project of CSIRO Marine and Atmospheric Research and the Australian Antarctic Division), will continue to document these changes.”

The results of the study will be published in the journal Global Change Biology.

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