waterways/wetlands – Page 29

Australia pledges more cash to battle reef starfish

government, pest species, waterways/wetlands

Jul 192013

Original story, AFP

SYDNEY, New South Wales — Australia pledged another Aus$5 million (US$4.6 million) to the fight against a predatory starfish devastating the iconic Great Barrier Reef Thursday, revealing 100,000 of the creatures had been wiped out so far.

Divers cull crown-of-thorns starfish on the Great Barrier Reef. Townsville Bulletin

Environment Minister Mark Butler said the new funding, on top of Aus$2.53 million already pledged, would support a programme of culling the coral-eating crown-of-thorns starfish, which is naturally-occurring but has proliferated due to pollution and run-off.

A major study of the reef's health published last year revealed coral cover had halved over the past 27 years and attributed 42 percent of the damage to the starfish.

Canberra formally downgraded the reef's health from moderate to poor last week, with cyclones and floods depleting water quality and reducing coral cover by 15 percent since 2009.

The government is under pressure to improve conditions on the reef, with UNESCO warning its World Heritage status will be declared at risk next year without action on rampant resources and coastal development in the region.

Butler said a special programme to reduce starfish numbers launched last year had seen 100,000 crown-of-thorns eradicated and the extra funding pledged Thursday would support a dedicated culling boat and divers.

"Importantly, it means crown-of-thorns starfish on high-value reefs are prevented from entering the next spawning season, and coral cover at high-value tourism sites, such as Lizard Island, has been maintained," Butler said of the progress made so far.

He said action on the starfish, which consumes coral faster than it can be regenerated, was urgent given the broader threat of global warming to the reef.

"Due to climate change, the incidence of extreme weather events have had an incredibly detrimental effect on the reef," Butler said.

"Also, since 1979 we've seen devastating coral bleaching occur across the reef nine times due to climate change and our warming sea waters, when there was no previous recorded occurrence."

Butler said tourism and related reef activities injected Aus$6.2 billion into the economy every year, employing 120,000 people and it was one of the nation's "most valuable assets".

"We must ensure we protect the reef and the jobs it supports, which is why acting to halt climate change and further damage to the reef, by cutting carbon pollution, is imperative," he said.

Stop marine pollution to protect kelp forests

environment, waterways/wetlands

Jul 182013

Media release, The University of Adelaide

University of Adelaide marine biologists have found that reducing nutrient pollution in coastal marine environments should help protect kelp forests from the damaging effects of rising CO₂.

Some of the remaining giant kelp (Macrocystis pyrifera) forest, which once covered much of the east coast of Tasmania. Mick Baron, ABC

The researchers have found a combined effect on kelp forests from nutrient pollution and higher CO₂, which could have a devastating impact on Australia's marine ecosystems.

"When we manipulated CO₂ and nutrient levels in an experimental marine ecosystem we found the effect of both of them together was greater than the sum of their individual impacts," says Dr Bayden Russell, of the University's Environment Institute and Senior Lecturer in the School of Earth and Environmental Sciences.

The project, by PhD student Laura Falkenberg, found that removing the nutrients from the water removed the combined effect, improving the environment for kelp growth.

Kelp forests are one of the most productive marine ecosystems in colder waters and form the basis of food webs for many fish and other marine life. "They are the coral reefs of colder waters," Dr Russell says.

"Increased nutrients from agriculture, wastewater discharge and stormwater on urban coasts are already causing damage to kelp populations in our coastal waters but our research shows that, as CO₂ rises the impacts will be much worse and we could lose these really important marine habitats," says Dr Russell.

The researchers grew kelp in experimental tanks floating in the North Haven Boat Harbour with different combinations of added nutrients and CO₂. They measured the growth of turf algae which is a precursor to kelp forest loss. As the turf algae grows it displaces the kelp.

"When we removed the nutrients but kept the CO₂ high we found that after six months we'd reduced the turf algae by 75% - we'd removed that synergistic effect," says Dr Russell.

"As we face a future of climate change and higher CO₂ levels, there is considerable evidence that our marine ecosystems are going to be severely impacted. We won't be able to manage those global factors at the local level, but what we can manage is local nutrient pollution into our seas from urban areas," he says.

"This work has shown that by reducing the nutrients we should be able to substantially reduce the impact of rising CO₂. The bottom line is that we need to reduce the nutrient pollution now."

The research is continuing with larger tanks, known as mesocosms, set up at West Beach and in natural marine areas where CO₂ seeps into the water from seabed volcanic activity in New Zealand.

Research shows Great Artesian Basin more extensive than thought

waterways/wetlands

Jul 182013

Original story at ABC News

Research has shown the outback Great Artesian Basin to be far more extensive than previously thought.

A small spring at Edgbaston. The springs have high ecological significance as they are permanent water in an arid landscape. Photo: Adam Kerezsy, Before it's Gone

Great Artesian Basin more extensive than thought. Photo: Peter Castle

The Arid Lands Natural Resources Management Board has been mapping the area in preparation for a formal revision of a 30-year-old water allocation plan for the vast outback zone.

Regional manager for sustainable water use, David Leek, said there were records of about 800 springs in the area, but new research had found about 5,000.

Mr Leek said the new information challenged early thinking that water moved underground from the east.

"What we now understand is that the system is much more complex, there's a number of different layers and that those layers are intersected by faults and fractures in the Earth's surface, so there is actually more of a connection between the layers than we understood in the past," he said.

Mr Leek said at current extraction rates the volume of water in the Artesian Basin was not at risk.

"What we need to make sure that we do is we actually maintain the pressure in the system, because it's the pressure in the system that actually drives springs and actually drives the the water to the surface and sustains the springs," he said.

The basin is under a vast area of South Australia, parts of New South Wales and Queensland and the south-east corner of the Northern Territory.

Kakadu river secrets begin to surface

environment, waterways/wetlands

Jul 172013

Original story by Carmen Brown, ABC Rural

Kakadu National Park is home to some of Australia's most iconic wetland landscapes, but will the environment always look the way it does now?

Researcher David Williams is working on water monitoring projects in Kakadu National Park. Photo: Carmen Brown

Scientists are trying to find out how the region's tropical river systems work, and what might happen to them as the climate changes.

Australian Institute of Marine Science researcher David Williams says measuring tidal activity and developing flow models is the first step.

The South Alligator floodplains in Kakadu National Park, Northern Territory. Photo: Carmen Brown

"Down at the mouth of the South Alligator we have recorded a six metre tide, and up at the bridge here we have a five and a half metre tide," he said.

"Those high tides produce a lot of energy, and strong tidal currents, and that moves sediment with it which has an impact on the biodiversity and life in the estuary.

"That's what we are trying to work out - what the physics are, and how they relate to the biology and health of the estuary."

Mr Williams says even small sea level changes could alter the region's freshwater habitats, and the life which they support.

"That's probably the threat that's foremost in people's minds, what will sea level rise do and what will the implications be for the future?" he said.

"In such a flat landscape it's something that we really need to consider.

"If sea level rises by only less than half a metre, a significant amount of the coastal floodplains will be inundated with salt water."

Mr Williams says saltwater incursion events could occur more often if storm and cyclone activity increases in a changing climate.

"What we've found in our research is that sea levels in this part of the world vary significantly between the dry season and the wet season," he said.

"It's because of the monsoon winds pushing the water up against the coast, that can make up to a 0.3 metre sea level rise just by wind strength.

David Williams on the banks of the South Alligator River, Kakadu National Park. Photo: Carmen Brown

"If we have increased cyclone activity or monsoonal strength, what effect does that have on the coast in terms of erosion and pushing water levels higher?"

In an area which attracts so many visitors, Mr Williams says any significant change to the environment could also impact local industries.

"What we need to understand is how does it affect tourism, because a lot of people obviously come here to look at wetlands, to look at the wildlife, a lot of people come here for fishing," he said.

"So is that going to affect the fish stocks in the river, it might not, but if the wetland areas which are nurseries for barramundi are impacted, then we could probably see a decline.

"But in the end, the area was marine in the past so if this is a cyclic change then there isn't really much we can do about it."

After working in northern Australian waters for more than 30 years, Mr Williams says he is still amazed by what he sees and learns about nature every day.

"The fact that we have these huge tides, and this water that just races in from the coast at incredible speeds and then just turns around and goes back out again," he said.

"It just never ceases to fascinate me the energy in these systems and what it supports, and just how it all works."

Antarctic marine park plan frozen out

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

Jul 172013

Original story by at The Age

An attempt by Australia to set up some of the world's largest marine reserves in Antarctica has been blocked at a meeting in Germany.

Fishing nations Russia and Ukraine questioned the legality of the move, according to Terje Lobach, chairman of the Commission for the Conservation of Antarctic Marine Living Resources.

More protection sought: A king penguin during sunset at its Auster rookery near the Australian research station of Mawson. Photo: AFP

Mr Lobach said that many nations in the organisation also had doubts about the size of one of the reserves, a 2.6 million-square-kilometre proposal for the Ross Sea.

The rocky passage of marine reserve plans led their main non-government advocate, the Antarctic Oceans Alliance, to say their future was in doubt before Tuesday's final session of the meeting in Bremerhaven.

Australia, France and the European Union put forward a network of seven reserves in waters covering 1.63 million square kilometres of eastern Antarctic waters, and the US joined New Zealand in proposing the Ross Sea reserve.

Advocates say they would give extra protection to some of the world's largest wild ocean areas, where species such as penguins, seabirds, seals and whales live largely unharmed.

Inside the commission, opposition to the reserves emerged eight months ago at its annual meeting in Hobart, and it was reinforced at an Antarctic Treaty meeting in May where a resolution of general support was scotched. Now at a rare special meeting of the commission, long-time Antarctic fishing nations are still holding out.

''The issue was raised, I can say, by Russia and the question was also raised by Ukraine, whether [the commission] really has the competence of establishing [marine protected areas],'' Mr Lobach said at a news conference.

He said many lawyers in the closed meeting spoke against Russia and Ukraine, and definitely said the commission had the power and mandate to establish protected areas in the high seas.

''The challenge is, of course, that we are working under consensus rule,'' Mr Lobach said. ''So we have to have everybody on board to have an agreement.''

An informed source told Fairfax Media that Russia did not believe other commission countries were ''behaving properly''.

But Steve Campbell, director of the Antarctic Ocean Alliance, said Russia and Ukraine's challenges to legality were groundless.

Commission executive secretary Andrew Wright said delegates were considering whether to open up some areas that were now closed to ''research fishing'' to demonstrate that the marine reserves system was not an attempt to exclude fishing.

''The commission … is still open to suggestions in terms of research fishing that might be conducted in areas that have been closed to fishing for several years,'' Mr Wright said.

Decision due on massive Antarctic marine sanctuaries

fisheries, government, waterways/wetlands, wildlife

Jul 162013

Proposed marine protected areas on the east Antarctic coastal region

Original story by Matt McGrath, BBC News

Negotiators meeting in Germany are set to decide on the establishment of the world's biggest marine reserves in Antarctica.

Scientists are hoping the plans for protected areas in the Ross Sea and in Eastern Antarctica will be supported.

But a previous attempt failed to get the necessary backing of all 25 members involved.

And there are worries that countries including Russia could again scupper the proposal.

The Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) is made up of countries with an interest in the Southern Ocean, and includes Australia, the US, the UK, China and Russia among its members. Any decisions taken require consensus among all parties.

This meeting in Bremerhaven has been called to deal specifically with proposals for the establishment of reserves that would ban fishing and protect species including seals and penguins. If successful the plans would more than double the area of the world's oceans that are protected.

The proposed protected zone in the Ross Sea is home to a large proportion of the world's Adelie penguins

Protecting penguins

The idea of creating marine protected areas has been around for several years - but when it came to a decision late last October, several countries including Russia, the Ukraine and China had reservations and the meeting ran out of time.

The US and New Zealand are again backing a proposal to create a marine protected zone in the Ross Sea with a total area of 2.3m sq km, making it the biggest in the world.

According to Andrea Kavanagh, director of the Pew Charitable Trusts' Southern Ocean campaign, this would have a major benefits for a range of species.

"While it is called the Ross Sea, a portion of it is frozen solid 365 a year and provides a critical habitat for hundreds of species of birds, mammals, fish and invertebrates including 38% of the world's Adelie penguins and 26% of the world's Emperor penguins," she said.

Another proposal from Australia, France and the European Union would create protected areas in East Antarctica covering around 1.63m sq km.

Australia's minister for environment, Mark Butler MP, said the East Antarctic proposal would be a significant undertaking but would be about more than just protecting species.

"The MPA also includes scientific reference areas where we can measure long term changes and natural variability - essential pieces of information to ensure the conservation of key features and the sustainability of fishing in the region," he said.

Fishing is a big sticking point with species like krill and patagonian toothfish proving highly lucrative for boats from a range of countries, including South Korea, Norway and Japan.

There has been rapid growth in fishing for Antarctic krill driven by demand for Omega-3 oil supplements

In for the krill

The tiny shrimp like Antarctic krill are a key element of the ecosystem, as they are part of the diet of whales, penguins, seals and sea birds.

However demand for krill has risen sharply in recent years thanks to growing interest in Omega-3 dietary supplements.

In the months since the last meeting in Tasmania, diplomats have been working hard to stress the scientific case for ending fishing in these regions of Antarctica.

"There were a number of issues raised by countries including China, Russia and the Ukraine, they related to issues such as access to fishing and there were questions about the science," Bob Zuur, from campaigners WWF.

"The proponents have heard those concerns and have prepared detailed responses - we expect that those issues have now been addressed."

Environmentalists are worried that there may be attempts at a compromise, with a proposal from Norway for what's termed a "sunset clause".

Supported by Russia and Japan it would mean the protected areas in the East Antarctic would be reviewed in 2064 and the Ross Sea in 2043. Campaigners say that this is an unusual idea, given that protected areas on land or in the seas are usually designated in perpetuity.

If the meeting doesn't come to a decision or it is likely that unanimity can't be achieved, it is possible that the meeting will refer the issue forward to CCAMLR's annual gathering towards the end of this year.

High CO2 Spurs Wetlands to Absorb More Carbon

environment, waterways/wetlands

Jul 162013

Under elevated carbon dioxide levels, wetland plants can absorb up to 32 percent more carbon than they do at current levels, according to a 19-year study published in Global Change Biology from the Smithsonian Environmental Research Center in Edgewater, Md. With atmospheric CO2 passing the 400 parts-per-million milestone this year, the findings offer hope that wetlands could help soften the blow of climate change.

The Smithsonian Environmental Research Center's Bert Drake holds up a cluster of Spartina patens, a marsh grass that absorbed more CO2 than his team expected. Drake's team looks into the future by filling marsh chambers with extra CO2, tracking how plants will grow over the next century.

Plant physiologist Bert Drake created the Smithsonian’s Global Change Ecological Research Wetland in 1987 at Edgewater. Back then, most scientists thought plants would gradually stop responding to rising CO2. Whether or not terrestrial ecosystems could assimilate additional carbon—and act as powerful carbon sinks—was not known. This study tracked not only how much CO2 wetlands absorb, but also the impact of rising temperature and sea level, changing rainfall and plant type.

To simulate a high-CO2 world, Drake’s team surrounded marsh plots with open-top Mylar chambers. For this study they left half of the chambers exposed to today’s atmosphere. In the other half they added CO2 and raised the level to 700 ppm, roughly doubling the CO2 concentration as it was in 1987. Other plots of land were left without chambers. They compared the levels of CO2 going in and CO2 going out to determine the carbon exchange between the wetland and the atmosphere.

Two types of plants populate most of the world, and the experiment tested both. C3 plants—which include more than 95 percent of the plant species on earth, including trees—form molecules of three carbon atoms during photosynthesis, and they tend to photosynthesize more as atmospheric CO2 rises. C4 plants form molecules of four carbon atoms. But for C4 plants, photosynthesis is saturated with CO2 at present levels. For that reason the team expected photosynthesis to increase in the C3 plants but not the C4 plants as they raised CO2. In this study, half the plots were dominated by the C3 sedge Scirpus olneyi and half by the C4 grass Spartina patens.

The C3 plants saw the largest increases. Over the 19-year study, they absorbed on average 32 percent more carbon under higher CO2 than under normal CO2. Most of the increase took place during the day, as the plants absorbed extra CO2 through photosynthesis. But the team was surprised to find that elevated CO2 also decreased the amount of carbon the plants lost at night through respiration. That reduction was due in part to a decrease in the amount of nitrogen in both types of plants when they grew in the high-atmospheric CO2. Also contrary to their expectations, the C4 plants saw a 13 percent increase under elevated CO2, also predominantly during the day but partially at night.

“We expected that more carbon would be assimilated during the day due to stimulation of photosynthesis,” Drake said. “We did not expect that loss of carbon at night would also be affected by the elevated CO2.”

However, climate also affected how much carbon the plants absorbed. For example, droughts crippled the C3 plants’ ability to take up carbon. During three dry years (1995, 1999 and 2002), they absorbed a mere 4 percent more CO2 on average under elevated versus normal conditions. Those three years also saw the lowest CO2 absorption overall. Other environmental factors related to climate change, such as sea-level rise and increasing temperature, also affected carbon assimilation.

Ecologists are still working out where all the extra absorbed carbon is going. According to their data, it does not all go into creating plant biomass. However, the plants do not show any sign of slowing their carbon absorption. “The results of this study suggest that wetland ecosystems will assimilate more carbon as atmospheric CO2 levels continue to rise beyond the level of 400 ppm reached in May 2013,” said Drake.

The accepted manuscript is available online. To view a copy of the full paper or speak to Drake, contact Kristen Minogue at minoguek@si.edu or 443-482-2325.

Are Aquariums Ruining Coral Reef Biodiversity?

fisheries, waterways/wetlands

Jul 122013

Rod Fujita, oceans director of research and development for the Environmental Defense Fund, contributed this article to LiveScience's Expert Voices: Op-Ed & Insights.

When people think of fisheries, they generally think of seafood. But there is another, surprisingly large fishery that has not made it into the headlines. Millions of people benefit from it, both financially and aesthetically, yet no international agencies are monitoring it — even though it may strongly impact coral reefs, the centers of ocean biodiversity.

That little-recognized resource is the ornamental fishery, which harvests fish and invertebrates for display in aquariums and as curiosities.

A reef aquarium at the London Aquarium. Photo: Daniel78, Wikimedia Commons

Impact on coral reefs

In a new paper on ornamental fisheries in the journal Fish and Fisheries, my colleagues and I note that the impacts of fisheries are not well understood, but they may be very large. The ornamental trade is focused on coral reefs, which are home to much of the world's marine biodiversity, and involves at least 45 source countries. Every year, this fishery removes an estimated 20 million to 24 million fish, many millions of corals and shells, and 9 million to 10 million additional invertebrates. [Colorful Creations: Photos of Incredible Coral Reefs]

Coral reefs are extremely productive and teem with colorful life . But they also use a lot of energy, and there is much competition and predation in reefs, thus resulting in relatively low, net biomass production. In contrast to cold, nutrient-rich waters that can support very high fishery yields, the warm, nutrient-poor waters typical of coral reefs are probably unable to sustain large harvests.

What to do?

Researchers know that the fisheries that decline and collapse tend to be those that are not managed or assessed. Therefore, the first step toward a solution is to assess the status of ornamental stocks and the coral reefs that support them.

In our paper, my colleagues and I lay out a step-by-step approach for assessing and managing fisheries for which data are limited, and illustrate the methods using data from Indonesian fisheries.

The first step in that approach is to assess the status of an entire coral reef — not just the fish stocks — and develop conservation targets aimed at maintaining or restoring healthy reefs.

The next step is to estimate the vulnerability of the stocks and their degree of depletion. That information is combined in a decision matrix: For each category of vulnerability and depletion, a different set of management measures is appropriate. For example, for a highly vulnerable species that is also highly depleted, a ban on fishing may be appropriate, whereas for more resilient species that are less depleted, harvest might be increased to allow other, depleted stocks to recover.

Nano reef aquarium maintained at a home. Photo: John Tan, Wikimedia Commons

Fishery managers can also use the decision matrix to prioritize stocks for more detailed assessments that can guide catch limits for high-priority stocks.

My colleagues and I hope this new analytical framework and management system will catch on before the ornamental fishery starts to generate headlines about a new fishery crisis.

This article was originally published on LiveScience.com .

Glass sponges take advantage of clear ‘skies’

environment, waterways/wetlands

Jul 122013

Original story by Stephen Pincock, ABC Science

In the freezing waters around Antarctica, pale sponges made of glass have spread rapidly across the seafloor as surface ice disappeared, German and Swedish researchers report.

Glass sponges are a group of long-lived, cup-shaped animals with skeletons made of silica, a major component of glass.

Typical glass sponge community in the Eastern Weddell sea, which is not covered by ice shelves. Image: Current Biology, Fillinger et al.

They once dominated the sea floor, but today the only place they are found in large numbers is in the Antarctic, explains Professor Claudio Richter, a marine biologist from the Germany's Alfred Wegener Institute for Polar and Marine Research.

"The sponges are large and vase-shaped and much of their bodies is made up of glass," says Richter, who co-authored a report on the sponges in the latest issue of the journal Current Biology.

"Not solid glass, but rather glass of a structure reminiscent of glass padding or mineral wool."

In the Antarctic, the sponges live in water that is below freezing (0°C), where for most of the year there is too little light to sustain the production of phytoplankton which forms the basis of the Antarctic food web.

Richter and his colleagues have been studying these creatures in the ocean that was once covered by the Larsen Ice Shelf, a thick floating ice platform that extended along part of the east coast of the Antarctic Peninsula.

"The permanent cover of the Larsen ice shelf severely limited life on the seafloor to an impoverished fauna reminiscent of the deep sea," says Richter.

However in recent decades, regional warming along the Antarctic Peninsula has caused the Larsen shelf to disintegrate, allowing seasonal blooms of the plankton to feed the wider food-chain.

Considering how cold the water is in this region, and the relative scarcity of food, the researchers had expected marine life to respond slowly to these environmental changes, Richter explains.

But after studying glass sponges in this area in 2007 and again in 2011 using a remotely operated underwater vehicle, researchers unexpectedly found that their abundance had increased dramatically.

"To our surprise, the sponge doubled their biomass and tripled their densities in only four years. This suggests that glass sponges are very efficient in using the scarce resources and can reproduce very fast."

Although there are many questions still to answer about these enigmatic organisms, the results are providing clues about how living ecosystems respond to environmental changes, Richter says. His team plans to keep going back to this polar site, to see what might happen next.

"We know now that not only the abiotic environment can change dramatically, [but] also the biota are changing, and they are changing fast."

"Whether or not they can keep pace with the abiotic changes is difficult to predict," he adds. "This is why it is important to follow these changes over time. This is an international effort, to which Australia is also contributing."

Research reveals estuary threats

pest species, waterways/wetlands

Jul 112013

Media release from Murdoch University

Two new studies have shed light on the health of Busselton’s waterways.

Researchers from Murdoch University spent time in the iconic Vasse-Wonnerup estuary, surveying introduced fish species and measuring nutrient levels in the sediment.

A goldfish, caught in the Vasse-Wonnanup estuary.

The introduced fish study and removal program, funded through the Caring For Our Country program, found that introduced fish species were thriving.

"In the estuary, we found 29 species of native fish, along with two introduced freshwater species," said Dr James Tweedley, of Murdoch University.

"Sadly, we found the highly invasive Eastern Gambusia in the estuary and in all four tributary rivers too."

The study also found that goldfish, which are not native to the area, seasonally invade the estuary following winter rains.

"These goldfish are highly mobile and seem to be able to tolerate saltier water," Dr Tweedley said.

"The big concern is that this ability could see goldfish using the estuary as a 'bridge' to colonise other rivers."

To track the goldfish, researchers used the same acoustic technology used to track Great White Sharks off the WA coast. The information gathered will assist future efforts to eradicate the species from the Vasse River and estuary.

The second study, funded by the South West Catchments Council, found that the levels of nutrients in the estuary are a cause for concern.

"The sediment we analysed from the bottom of the estuary was high in nutrients. But sediment collected from the water itself had up to 16 times more nitrogen and phosphorus," Dr Tweedley said.

"If these high levels of nutrients continue, it could result in a collapse of the sea grass meadows in areas of the estuary, with flow on effects to the rest of the ecosystem."

The results of these studies, and its implications, will be discussed at a free public lecture in Busselton on July 17. For more information about this event, please contact Jen Mitchell from GeoCatch on 9781 0111 or jen.mitchell@water.wa.gov.au.

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