waterways/wetlands – Page 27

New fish discovered by Fluval during Colombia expedition

Aug 022013

Fluval has announced that a new species of Pike cichlid was discovered during a recent company-sponsored expedition to Colombia, which will be shared with the aquatic world in a soon-to-be-released Fluval documentary.

For 13 days near the end of the latest Colombian dry season, Fluval’s Tom Sarac led a team of aquatic explorers across 2,600 km/1,600 miles of the Llanos, a vast tropical grassland plain situated to the east of the Andes.

The group’s mission was three-fold; to understand and witness this rich bio-diverse environment firsthand, implement their learnings into habitat-accurate products for the home aquarium hobby and, lastly, bring awareness to help protect this precious natural environment from threats such as deforestation, mining and oil/gas production.

The discovery of the new fish, with a unique “W” shaped trident marking located near its gills, will be featured in Fluval’s upcoming Colombia Expedition film, which will be released in conjunction with the launch of the all-new Fluval Aquatics website later next month. Aquatic fans are encouraged to register on the Fluval home page now in order to be alerted as soon as the site goes live.

A one-minute long trailer of the Colombia Expedition has been released, which can be viewed below.

Anglers raise their concerns over fish numbers

community, fisheries, waterways/wetlands

Aug 022013

A SURVEY of recreational fishers in the Mackay region has revealed many hold serious concerns for fish numbers if the proposed Dudgeon Point Coal Terminal goes ahead.

Land allocated for Dudgeon Point: The two proposed terminals will provide export capacity up to 180 million tonnes per year, which is 50 million tonnes more than the current capacity at the Hay Point port. Source: Google Maps

Environment group Communities Protecting Our Region surveyed 264 recreational fishers during the months of May and June.

The survey found 83% thought dredging would have an impact on recreational fishing, 87% thought dredging would impact water quality and 81% thought increased coal ships would adversely affect the reef and fish.

While Dudgeon Point's environmental impact statement is yet to be released, dredging of 13-15 million cubic metres of sediment has been proposed for the project.

Mackay Recreational Fishing Alliance president Lance Murray said his main concern was the exclusion zone that would be established if Dudgeon Point went ahead. "It's a compounding situation where it forces more people into a funnel, fishing in closer proximity to one another," he said.

A spokesperson for North Queensland Bulk Ports, the proponent of the Dudgeon Point project, has shot holes through the report, saying the survey was based on people's perceptions, not fact.

The survey predicted once Dudgeon Point was operational, shipping numbers at Hay Point would increase to more than 4250 per annum.

NQBP Regional Relationship Practitioner Simon Eldridge said this was wrong. "The Port of Hay Point has handled up to 1100 ships in a year," he said.

"Under the expected moderate growth scenario for the Dudgeon Point project, shipping into Hay Point is expected to reach 1530 ships by 2020, but actual numbers will depend upon market demand.

"This is far less than the inflated number of 4250."

Gladstone Harbour flooding, rather than dredging caused sick fish: report

fisheries, government, waterways/wetlands

Aug 022013

Original story by AAP at The Australian

A FINAL report on sick fish in Gladstone Harbour says flooding - not dredging - was the main cause of the problem.

The report says flooding, combined with large numbers of fish being washed over the Awoonga dam, stressed the ecosystem in the central Queensland city's harbour and adjacent waterways.

Gladstone Harbour, Queensland, where the death and disease of local fish and marine life has been found to be caused by flooding. Picture: Hunter Vanessa Source: The Australian

"This study cannot rule out the possibility that the activity of dredging and associated turbidity provided additional stress to the ecosystem, but it was not the primary stressor," says the report, released on Friday.

The report was the work of an independent panel of investigators appointed by the government to investigate concerns about sick fish in the waterway.

It said the first reports of abnormalities in fish were received months after a major flood in Gladstone from December 2010 until early 2011.

"The flood event caused a dramatic influx of large barramundi (estimated 30,000), as well as other species from Lake Awoonga into the Boyne River when the Awoonga Dam spilled over," it said.

"The dam had not spilled over since the 1990s, well before the dam wall was raised in 2002.

"Many of these fish were injured (some fatally) from the force of the impact when passing over the spillway."

It said the health of fish in Gladstone Harbour returned to a more normal situation in 2012.

"All industrial activities in Gladstone that were operating in Gladstone in 2011 have continued to operate, including dredging," the report notes.

"The only factor different in 2011 compared to previous years was the significant rainfall, the subsequent flooding and the introduction of a significant biomass of fish from Lake Awoonga."

The report said flooding had also occurred in 2012 and this year.

But other than continuing reports of barramundi showing damage as a result of being washed over the spillway, there have been no reports of any recurrence of sick fish.

"The most likely cause of the abnormalities observed during this investigation is the sudden introduction of barramundi and other fish from Lake Awoonga during December 2010 to early 2011," the report says.

A diseased barramundi caught in Gladstone Harbour. Source: Supplied

"Although barramundi are naturally able to move between fresh and salt water environments, it appears that these fish were overcrowded and unable to feed normally after they were suddenly re-located from Lake Awoonga into the Boyne River.

"The stress preceded parasitic infestation during the colder winter water temperatures in 2011."

That infestation subsided as the water temperature increased and fish density reduced, as shown by improving fish health in late 2011 and 2012, the report said.

Significantly higher arsenic, cadmium, iron and zinc concentrations were found in barramundi livers in the Gladstone area, the report said.

That indicated the fish had greater exposure to metals and metalloids.

But no elevated levels of these metals were found in the tissues of diseased barramundi compared to healthy ones.

The report concluded metals and metalloids were unlikely associated to the fish health in the harbour.

Metal concentrations in crabs were found to be similar to crabs along the east coast.

"Overall, there is no strong evidence of a link between fish health at the time of sampling and tissue residue concentrations," it said.

Sediment trapped behind dams makes them ‘hot spots’ for greenhouse gas emissions

environment, waterways/wetlands

Aug 022013

Media release from ACS

"Sediment Trapping by Dams Creates Methane Emission Hot Spots"
Environmental Science & Technology

With the “green” reputation of large hydroelectric dams already in question, scientists are reporting that millions of smaller dams on rivers around the world make an important contribution to the greenhouse gases linked to global climate change. Their study, showing that more methane than previously believed bubbles out of the water behind small dams, appears in ACS’ journal Environmental Science & Technology.

Photo: iStockphoto/Thinkstock

Andreas Maeck and colleagues point out that the large reservoirs of water behind the world’s 50,000 large dams are a known source of methane. Like carbon dioxide, methane is one of the greenhouse gases, which trap heat near Earth’s surface and contribute to global warming. Methane, however, has a warming effect 25 times more powerful than carbon dioxide. The methane comes from organic matter in the sediments that accumulate behind dams. That knowledge led to questions about hydroelectric power’s image as a green and nonpolluting energy source. Maeck’s team decided to take a look at methane releases from the water impoundments behind smaller dams that store water less than 50 feet deep.

They describe analysis of methane release from water impounded behind six small dams on a European river. “Our results suggest that sedimentation-driven methane emissions from dammed river hot spot sites can potentially increase global freshwater emissions by up to 7 percent,” said the report. It noted that such emissions are likely to increase due to a boom in dam construction fostered by the quest for new energy sources and water shortages.

The authors acknowledge funding from the German Research Foundation.

Polar ecosystems vulnerable to sunlight

environment, waterways/wetlands

Aug 022013

Media release from UNSW

Slight changes in the timing of the annual loss of sea-ice in polar regions could have dire consequences for polar ecosystems, by allowing a lot more sunlight to reach the sea floor.

Fan worms (turquoise) and sponges (orange) under the sea ice in Antarctica near Casey Station. Photo: Graeme Clark

The research by scientists at UNSW and the Australian Antarctic Division predicts that biodiversity on some areas of the polar seabed could be reduced by as much as one third within decades, as the poles warm.

The study, Light-driven tipping points in polar ecosystems, will be published in the journal Global Change Biology.

Dr Graeme Clark, of the UNSW School of Biological, Earth and Environmental Sciences, says the team’s research shows that polar ecosystems may be even more sensitive to climate change than previously thought.

“Even a slight shift in the date of the annual sea-ice departure could cause a tipping point, leading to widespread ecosystem shifts. On the Antarctic coast this may cause unique, invertebrate-dominated communities that are adapted to the dark conditions to be replaced by algal beds, which thrive on light, significantly reducing biodiversity,” Dr Clark says.

The invertebrates lost could include sponges, moss animals, sea squirts and worms. These animals perform important functions such as filtering of water and recycling of nutrients and provide a food source for fish and other creatures.

“This is a prime example of the large-scale ecological impacts that humans can impose through global warming – even in places as remote as Antarctica,” says UNSW team member, Associate Professor Emma Johnston.

“Our modelling shows that recent changes in ice and snow cover at the poles have already transformed the amount of light reaching large areas of the Arctic and Antarctic annually.”

For the study, the team deployed light meters on the sea floor at seven sites near Casey Station in Antarctica, at depths of up to 10 metres. They used cameras to photograph the coast at midday every day for two and a half years, to determine sea-ice cover.

They determined the growth rates of Antarctic algae in the lab in different light conditions, and conducted experiments in Antarctic waters to test the sensitivity of algae to available light. They also surveyed species living on sub-tidal boulders, to see how communities varied with ice cover.

Tipping points are events where small changes in environmental conditions cause rapid and extensive ecological change.

The amount of sunlight reaching the poles is highly dependent on the seasons because the Earth’s tilt causes the sun to be above the horizon for considerably longer during summer than winter, and the lower solar angle during winter increases reflectance from the water surface.

“Early melt that brings the date of sea-ice loss closer to midsummer will cause an exponential increase in the amount of sunlight reaching some areas per year,” says Dr Clark.

Media contacts:

Dr Graeme Clark: 9385 1711, g.clark@unsw.edu.au

Associate Professor Emma Johnston: 9385 1825, e.johnston@unsw.edu.au

UNSW Science media: Deborah Smith: 9385 7307, 0478 492 060, deborah.smith@unsw.edu.au

Townsville Sea Simulator centre opens

aquarium, environment, government, pest species, waterways/wetlands

Aug 012013

Original story by David Chan, ABC News: Townsville Sea Simulator centre opens, targets coral-killing crown of thorns starfish

National Sea Simulator in Townsville

Scientists say the National Sea Simulator, which is being opened in north Queensland today, represents a quantum leap for marine research.

The $35 million federally-funded research aquarium, also known as SeaSim, is based at the Australian Institute of Marine Science (AIMS) in Townsville and scientists will use it to recreate ocean conditions for their experiments.

It will give researchers precise control over variables including temperature, salinity and water quality.

The institute's chief executive, John Gunn, says SeaSim represents a quantum leap for marine research in Australia.

"This facility allows us to look at the multiple different factors, what we call the cumulative impacts, of human use in the zone of reefs and inshore areas," he said.

"So this is going to be a nerve centre of an advance that I think will be unparalleled globally."

Mr Gunn says research facility will help scientists study the long-term effects of climate change, ocean acidification and dredging.

"It allows groups of scientists from AIMS, from universities such as James Cook [University] and all around the world to come together some of the big questions," he said.

Researchers to target killer starfish

Crown of Thorns Starfish (Acanthaster plancii) in the Townsville Sea Simulator display aquarium

Crown of Thorns Starfish (Acanthaster planci) in the Townsville Sea Simulator display aquarium

Combating the crown of thorns (COT) starfish, one of the biggest killers of coral of the Great Barrier Reef, and considered a major threat to the world-heritage listed site, will be one of the centre's main priorities.

AIMS research director, Jamie Oliver, says scientists are hoping to learn more about the starfish.

"We're very keen to replicate some of the original experiments which strongly suggest that for instance, nutrients are a major factor in causing COT outbreaks but we need to be able to replicate that work under much controlled and detailed circumstances," he said.

He hopes the research will also lead to more effective ways of controlling the predator.

"We can do that through for instance seeing whether there are special chemicals called pheromones which may attract crown of thorns starfish together," he said.

"If we can attract them together we may be able to use it as a way of putting out baited traps and collect much larger number of COTs."

Innovation, Industry, Science and Research Minister Kim Carr says he hopes SeaSim will help authorities and businesses better understand the impacts from things such as ocean warming and acidification.

"Our standards of living depend on having viable industries, including fishing, exports of our gas and mineral resources, as well as sectors like tourism but it is equally important we look after our marine resources carefully and responsibly," Senator Carr said.

"Public science and research agencies such as AIMS are the most invaluable assets we have in terms of getting this balance right based on the best available evidence."

Fraser Island Conferences only come around every two years

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

Aug 012013

Original story by John Sinclair, Fraser Coast Chronicle

Eli Creek, Fraser Island. Photo: Photnart, WikiMedia Commons

IF YOU'RE interested in Fraser Island then consider attending the coming Fraser Island conference on August 8 at the Mt Coot-tha Botanic Gardens auditorium in Brisbane.

Conference organiser, John Sinclair from the Fraser Island Defenders Organisation said it will more than justify people's interest and participation as it brought together a rare mix of scientists and stakeholders to discuss the issues of Fraser Island.

He said the conference also aimed to advance the island's case for its wider use as a natural laboratory and to better see the island's values with a global perspective.

"The hot topic of Fraser Island dingoes will be addressed by University of Queensland's Dr Greg Baxter who will report on the results of a satellite-tracking program that followed 18 Fraser Island dingoes over eight months to see what could be learnt on dingo behavior," Mr Sinclair said.

Climate Change, Biodiversity and Fraser Island is the subject of an address by Professor Roger Kitching, a co-ordinating lead author engaged in production of the next report of the Intergovernmental Panel on Climate Change.

Writer, broadcaster and Australia's longest serving science minister Barry Jones will deliver the keynote address drawing on his experience with UNESCO and as vice-president of the World Heritage Committee.

Mr Sinclair said the contributions of Prof Kitching and Dr Jones should add more justification for Fraser Island to be treated as a natural laboratory for climate change and this was the theme of this year's conference that is supported by the Fraser Island Natural Integrity Alliance and the Fraser Island Scientific Advisory Committee.

A global spotlight will be shone on the Fraser Island patterned fens in November when 10 leading peat scientists from the International Mire Conservation Group will visit Fraser Island fens following up the research of Patrick Moss, who will be reporting on his discoveries to the conference.

Another researcher, Jock McKenzie from James Cook University will report on his studies of the mangroves of Great Sandy Strait he has undertaken as part of his doctoral studies

"It won't only be scientists talking because Fraser Island is acclaimed as much for its outstanding aesthetic qualities as it is for its natural beauty and aesthetic qualities that are going to be discussed by leading Australian artist, Liz Cumming," Mr Sinclair said.

Additionally there will be poster presentations covering topics from visitor responses to dingo management, ground orchids, monitoring sediment movement, managing weeds and the coordination of research effort.

The conference will be held at the Mt. Coot-tha Botanic Gardens Auditorium from 9am to 5pm on Thursday, August 8.

Registrations are now open at fraserislandconference2013.eventbrite.com.au.

Further details can be found at www.fido.org.au.

Fish farm fallout review delivers a favourable finding

fisheries, government, waterways/wetlands

Aug 012013

Fish farm pens at Huon Aquaculture in southern Tasmania. The report gives the salmon industry a clean bill of health, despite some nutrient release. Photo: Conor Duffy, ABC News

Original story at ABC News

Scientists say the latest report on salmon farming in southern Tasmania shows the industry is healthy and sustainable.

Researchers at the Institute for Marine and Antarctic Studies have been monitoring the release of nutrients by fish farms in the D'Entrecasteaux Channel and Huon estuary between 2009 and 2012.

The study also reviewed the effectiveness of the Government's monitoring program.

Professor Colin Buxton says the report gives the salmon industry a clean bill of health, despite some nutrient release.

"It's very clearly demonstrated that there are no adverse consequences for the environment," he said.

"So the nutrient load that's coming into the system through salmon farming is at an acceptable level and certainly below the cap that the government set for them."

Rivers need snags for fish

environment, fisheries, waterways/wetlands, wildlife

Aug 012013

Original story by Chris McLennan, Weekly Times Now

MOST Victorian rivers require more snags to improve health and increase fish numbers, according to a new survey.

The Department of Environment and Primary Industries counted the snags in 27,700km of rivers, using aerial photography and on-ground mapping.

Woody habitat in Victorian rivers was an average of 41 per cent below natural levels. Photo: EPA Victoria

"Our modelling shows the amount of woody habitat in our rivers was an average of 41 per cent below natural levels and we know that is having a significant impact on freshwater fish species," DEPI fish ecologist Zeb Tonkin said.

However, in the 1970s and '80s governments funded the clearing of creeks and rivers of fallen trees and branches because they blocked water flows, particularly during floods.

Governments funded stream improvement trusts administered by local councils.

The DEPI survey found areas needing most re-snagging work included the southwestern floodplains, Glenelg and North Central floodplain river regions.

In comparison, the Alpine, North East Uplands and East Gippsland Upland regions were in relatively good condition, Mr Tonkin said.

The Government will use the survey to prioritise areas for restoration. Snags will be put back and riparian zones revegetated.

"We know that numbers of threatened native species such as Murray cod do increase in response to habitat restoration and the same applies to many other native species," Mr Tonkin said. "In the past snags were removed from our rivers because it was incorrectly thought that they reduced flows and contributed to flooding."

Research has since shown snag removal has minimal impact on flood mitigation, impairs river stability and affects the health of our streams, such as reducing fish populations.

"Over the past 20 years we have been gradually returning snags to our waterways particularly through the efforts of Catchment Management Authorities," Mr Tonkin said."

Environment Victoria chief executive Kelly O'Shannassy said many of the state's rivers and streams had been treated as drains and now they were being properly considered as functioning eco-systems.

Trout with tolerance to heavily polluted water

fisheries, waterways/wetlands

Aug 012013

Press release from the University of Exeter at EurekAlert!

New research from the University of Exeter and King's College London has shown how a population of brown trout can survive in the contaminated waters of the River Hayle in Cornwall where metal concentrations are so high they would be lethal to fish from unpolluted sites. The team believe this is due to changes in the expression of their genes. The research was funded by NERC and the Salmon and Trout Association.

Brown Trout (Salmo trutta). Photo: Tim Martin at BBC

The researchers compared the trout living in the River Hayle with a population living in a relatively clean site in the River Teign. The results showed that the accumulation of metals in the kidney and liver – where metals are stored and detoxified - were 19 and 34 times higher in the Hayle trout, respectively. In the gill, concentrations averaging 63 times higher were present in the Hayle fish, but there were no differences in metal content in the gut. This accumulation of metals in the Hayle fish highlights their extraordinary tolerance of the extreme metal concentrations in their environment.

In order to investigate how the Hayle brown trout are able to tolerate such high levels of metal exposure, and also look for potential signs of toxicity, advanced high throughput sequencing was conducted at the Exeter Sequencing Facility to sequence the genes and then measure changes in their expression between the two river sites. The gene encoding a protein, metallothionein, responsible for binding, storing and detoxifying a number of metals, was found to be highly expressed in the River Hayle trout, indicating its importance in their ability to tolerate metals in their environment. Evidence of the presence of other metal-binding and transporting proteins, particularly those responsible for handling iron, was also found.

Usually metals cause toxicity in fish by causing oxidative damage and disrupting the balance of ions in the body. The team found evidence that to counter this toxicity, Hayle fish showed changes in genes responsible for maintaining the balance of these ions in the body and a modest increase in anti-oxidants.

This work was led by T. Uren Webster, Dr R. van Aerle and Dr E Santos from the University of Exeter and Dr N Bury from King's College London, and has been published in the journalEnvironmental Science & Technology.

Tamsyn Uren Webster said: "The work demonstrates that this population of brown trout has developed strategies for dealing with the metal pollution in the water and accumulation in their tissues avoiding the lethal damage that such concentrations of metals would normally cause."

A detailed understanding of how the Hayle trout population has developed this tolerance could have potential implications for re-stocking rivers and increasing food security in polluted regions of the world.

Dr Eduarda Santos said: "The story of the brown trout in the river Hayle is a fascinating one, demonstrating its resilience and its ability to defeat the odds and tolerate the challenges imposed upon them as a result of human activities. Many aspects of this story remain untold: we do not know how or when this tolerance has arisen, and, most importantly, we do not know what the future holds for them if they are challenged with further stressors in their environment. But we know that such populations need careful management; if the Hayle brown trout, with their unique physiology, were to be lost, it is possible that this river may never be home to brown trout again. Therefore, understanding the relationship of fish with their environment is a crucial requirement to effectively manage and protect our aquatic ecosystems."

Dr Nic Bury said: "Cornwall has a rich history of mining activity. Despite the cessation of the majority of this activity in the 19th and 20th centuries a number of rivers and estuaries, still possess elevated metals. Brown trout are extremely sensitive to metals when tested in the laboratory. However, biology is remarkable and adaptable, and it is astonishing that trout are able to survive and flourish in the river Hayle. It may be that this population is unique and an important component of the genetic diversity of brown trout."

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