research – Page 4 – ANGFA Queensland

UQ Pitch Drop finally recorded

Apr 192014

Original story by Celeste Biever and Lisa Grossman, New Scientist

The pitch has dropped – again. This time, the glimpse of a falling blob of tar, also called pitch, represents the first result for the world’s longest-running experiment.

Sadly however, the glimpse comes too late for a former custodian, who watched over the experiment for more than half a century and died a year ago.

Up-and-running since 1930, the experiment is based at the University of Queensland in Australia and seeks to capture blobs of pitch as they drip down, agonisingly slowly, from their parent bulk.

It was pipped to the post last year when a similar experiment, set up in 1944 at Trinity College Dublin in Ireland, captured the first ever video footage of a blob of pitch dropping.

In that instance, the blob separated from its parent bulk. By contrast, the Australian team filmed the collision between the ninth blob ever to fall and the eighth blob, which was sitting at the bottom of their beaker – but the ninth blob is still attached to the pitch above it.

Still, the Australian result is important because the experiment has a better set-up, says Stefan Hutzler, a member of the Trinity College Dublin team who used those results to calculate the pitch’s viscosity. “Theirs is in a glass container; they measure the temperature, measure the humidity as well,” he says. “Ours, we don’t really call it an experiment. It was really just sitting there on a shelf, going back to the 1940s.”

Near miss

The fact that both experiments dropped within a year of each other is “just pure luck”, says Hutzler. Hot summer weather in Ireland last year may have influenced the timing.

The Queensland experiment already features in the Guinness World Recordsand won an IgNobel prize in 2005. It was set up by physicist Thomas Parnell to illustrate that although pitch appears solid, shattering when hit with a hammer at room temperature, it is actually a very viscous liquid.

The eventual result follows several near misses, according to the University of Queensland. John Mainstone, who oversaw the experiment for more than 50 years until his death last August, missed observing the drops fall three times – by a day in 1977, by just five minutes in 1988 and, perhaps most annoying, in 2000, when the webcam that was recording it was hit by a 20-minute power outage.

“It’s a pity of course that the person in charge died about a year ago, so he never saw the drop,” Hutzler says. “He would have enjoyed that.”

Honey flow

The eighth and ninth drops each took about 13 years to fall, says current custodian Andrew White. By contrast, the seven drops that fell between 1930 and 1988 did so faster – at an average rate of one drop every eight years.

The next step is to see how long it takes the ninth drop to separate from the pitch above it: “It may tip over quickly or it might slow right down and take years to break away,” says White.

You can keep an eye on the ninth drop’s movements via a live web stream. The University of Queensland says it will work out who was watching when the pitch dropped and record their names for posterity.

The drop experiments show that the physics of a drop forming in a viscous material is still not well understood, Hutzler says – although he doesn’t think watching pitch for decades is necessarily the best way to study it. Using honey or some other less viscous fluid would give you better statistics.

“I think these experiments capture the imagination just because they go on for such a long time,” he says. The video of the drop in Dublin quickly went viral on YouTube. “Ironically, you have a very slow event happening, but the news spreads very quickly.”

Fishing for facts about rivers’ unwelcome intruders

Apr 182014

Original story by John Thistleton, Canberra Times

Along the bottom of the beautiful Murrumbidgee gorge south of Canberra science is turning up the heat on huge carp.

Senior fisheries technician Prue McGuffie of the NSW Department of Primary Industries with a carp that didn’t get away. Photo: Jay Cronan

In the first project to track carp in an upland river system in NSW, data will be gathered to learn seasonal migration patterns and the best opportunities to trap large numbers of aggregating carp.

Using fine nets and electro fishing, researchers gathered in carp, cod and freshwater prawns on Tuesday.

Acoustic tags were inserted into some of the big carp, which were released back into the eight-metre-deep hole at Bush Heritage Australia’s ”Scottsdale” reserve.

The tag sends out a ping to a listening station in a white buoy in the river. Every time a tagged fish passes, the station records a ping, enabling researchers to download information every few months.

Other carp were dissected to remove their ear bone to determine their age, a key to analysing population structure and determining good years of spawning.

Senior NSW Fisheries technician Prue McGuffie, who netted the hulking, slimy green and grey carp, also kept a watch out for endangered Macquarie perch, which she is researching.

Ms McGuffie netted two cod fingerlings that she will genetically test to determine if they are Murray cod or trout cod.

Meanwhile, on the banks with varying vested interests, scientists, a fly fisherman and a potato farmer’s son watched intensely as a four-kilometre stretch of the river was netted.

Fisherman Steve Samuels is providing local knowledge for the project, and can recount the 1970s when the Murrumbidgee teemed with spawning silver perch. ”You’d only see one or two carp,” he said. ”Trout were all the way up the river.”

Laurence Koenig, whose family grows organic garlic and potatoes on ”Ingelara” next door to Scottsdale, was there to collect dead carp, humanely dispatched in a tub of ice.

Mr Koenig hopes researchers will continue to catch carp from the big hole. It could give him a tonne of fertiliser at each trapping session.

University of Canberra ecologist Mark Lintermans netted the hole overnight for juvenile Macquarie perch, but came up empty-handed.

”They are a long-lived species, so that is not a problem; it just means they have missed a year,” Dr Lintermans said.

Bush Heritage regional manager Peter Saunders said data would determine the best carp removal and control options to safeguard native fish. “We hope this work will fill a gap in Australia’s understanding of carp biology and behaviour in upland river systems, and guide new trials for targeted carp removal to better protect our native fish and river habitats,” he said.

Dr Lintermans said that if carp moved broadly along the river, trapping may not be effective. If they stayed in one spot, they could be controlled.

Observations so far show carp will jump barriers like waterfalls, whereas native fish will not. Carp will congregate in warmer pockets of the river and, at other times, for bait feeding or spawning. Dr Lintermans said Murray cod were rare in that section of the river.

NSW researchers begin trial to search for carp ‘Achilles heel’

Australian native freshwater species, community, fisheries, government, pest species, research, waterways/wetlands

Apr 152014

Original story by Jake Sturmer, ABC News

Researchers in New South Wales have begun a trial to search for the “Achilles heel” of carp.

Carp Etch. Image: DAFF Qld

The introduced species is considered to be one of the world’s most invasive and scientists say they are Australia’s worst aquatic pest.

The project will tag and track carp in the upper Murrumbidgee River, which have played a part in the significant decline of native fish.

Scientists estimate 90 per cent of all native fish have been lost in the river since European settlement.

University of Canberra Associate Professor Mark Lintermans says the fish have had a significant impact on the waterways.

“[They compete] for food, they carry parasites that then spread on to native fish,” he said.

“There’s even a suggestion that they might be hoovering up eggs of native fish as they feed along the bottom.”

The research is being done with the New South Wales Department of Primary Industries and Bush Heritage Australia in its Scottsdale Reserve.

“This project is initially about gathering information – there’s a gap of knowledge of the carp in the upper reaches of the Murrumbidgee,” reserve manager Peter Saunders said.

“So we’re looking to understand what they’re doing, where they’re aggregating, what their populations are and how they’re breeding and where they’re breeding.

“Then [we plan to] expand that project into actually starting to remove them to benefit the native fish which we know are in here in small numbers.”

Local angler and member of the Capital Region Fishing Alliance, Steve Samuels, says a lot has changed since he began fishing in the river in the 1970s.

“There was Murray Cod, Golden Perch, Silver Perch – it was a wonderful place to fish,” he said.

“But today as you see it, the water’s a lot dirtier and carp now dominate as the most prolific fish in the system.”

Contact Investigations@abc.net.au

Making dams safer for fish around the world

fisheries, research, waterways/wetlands

Apr 152014

Media release by Tom Rickey, Pacific Northwest National Laboratory

Fish-friendly hydropower is the goal of international team

Zhiqun (Daniel) Deng (l) and Rich Brown in the Three Gorges Dam in China.

Think of the pressure change you feel when an elevator zips you up multiple floors in a tall building. Imagine how you’d feel if that elevator carried you all the way up to the top of Mt. Everest — in the blink of an eye.

That’s similar to what many fish experience when they travel through the turbulent waters near a dam. For some, the change in pressure is simply too big, too fast, and they die or are seriously injured.

In an article in the March issue of the journal Fisheries, ecologists from the Department of Energy’s Pacific Northwest National Laboratory and colleagues from around the world explore ways to protect fish from the phenomenon, known as barotrauma.

Among the findings: Modifying turbines to minimize dramatic shifts in pressure offers an important way to keep fish safe when passing through dams. The research is part of a promising body of work that aims to reduce such injuries by improving turbine designs in dams around the world.

PNNL researchers are working with officials and scientists from Laos, Brazil, and Australia — areas where hydropower is booming — to apply lessons learned from experience in the Pacific Northwest, where salmon is king and water provides about two-thirds of the region’s power. There, billions of dollars have been spent since 1950 to save salmon endangered largely by the environmental impact of hydropower.

Colorized photo of the swim bladder of a smallmouth bass.

“Hydropower is a tremendous resource, often available in areas far from other sources of power, and critical to the future of many people around the globe,” said Richard Brown, a senior research scientist at PNNL and the lead author of the Fisheries paper.

“We want to help minimize the risk to fish while making it possible to bring power to schools, hospitals, and areas that desperately need it,” added Brown.

Harnessing the power of water flowing downhill to spin turbines is the most convenient energy source in many parts of the world, and it’s a clean, renewable source of energy to boot.

In Brazil, several dozen dams are planned along the Amazon, Madeira and Xingu rivers — an area that teems with more than 5,000 species of fish, and where some of the largest hydropower projects in the world are being built. In southeastern Australia, hydropower devices are planned in the area drained by the Murray-Darling river system. And in Southeast Asia, hundreds of dams and smaller hydro structures are planned in the Lower Mekong River Basin.

The authors say the findings from a collaboration that spans four continents improve our understanding of hydropower and will benefit fish around the globe. New results about species in the Mekong or Amazon regions, for instance, can inform fish-friendly practices in those regions of the United States where barotrauma has not been extensively studied.

To ‘Everest’ and back in an instant

Dams vary considerably in the challenges they pose to migrating fish, and the challenges are magnified when a fish must pass through more than one dam or hydro structure. At some, mortality is quite high, while at others, such as along the Columbia River, most fish are able to pass over or through a single dam safely, thanks to extensive measures to keep fish safe. Some fish spill harmlessly over the top, while others pass through pipes or other structures designed to route fish around the dam or steer them clear of the energy-producing turbines.

Researcher John Stephenson observes young salmon in a chamber used to simulate the conditions that fish sometimes experience as they travel through a dam.

Still, at most dams, the tremendous turbulence of the water can hurt or disorient fish, and the blades of a turbine can strike them. The new study focuses on a third problem, barotrauma — damage that happens at some dams when a fish experiences a large change in pressure.

Depending on its specific path, a fish traveling through a dam can experience an enormous drop in pressure, similar to the change from sea level to the top of Mt. Everest, in an instant. Just as fast, as the waters swirl, the fish suddenly finds itself back at its normal pressure.

Those sudden changes can have a catastrophic effect on fish, most of which are equipped with an organ known as a swim bladder — like a balloon — to maintain buoyancy at a desired depth. When the fish goes deeper and pressures are greater, the swim bladder shrinks; when the fish rises and pressure is reduced, the organ increases in size.

For some fish, the pressure shift means the swim bladder instantly expands four-fold or eight-fold, like an air bag that inflates suddenly. This rapid expansion can result in internal injuries or even death.

Factors at play include the specific path of a fish, the amount of water going through a turbine, the design of the turbine, the depth of water where the fish usually lives, and the physiology of the fish itself.

“To customize a power plant that is the safest for the fish, you must understand the species of fish in that particular river, their physiology, and the depth at which they normally reside, as well as the tremendous forces that the fish can be subjected to,” said Brown.

PNNL scientists have found that trying to keep minimum pressure higher in all areas near the turbine is key for preventing barotrauma. That reduces the amount of pressure change a fish is exposed to and is a crucial component for any turbine that is truly “fish friendly.” Preventing those extremely low pressures also protects a turbine from damage, reducing shutdowns and costly repairs.

Chinook salmon

Lower Mekong River Basin

Brown and PNNL colleague Zhiqun (Daniel) Deng have made several trips to work with scientists in Southeast Asia, where dozens of dams are planned along the Mekong River and its tributaries. The Mekong starts out high in Tibet and travels more than 2,700 miles, touching China, Myanmar, Laos, Thailand, Cambodia, and Vietnam. The team estimates more than 1,200 species of fish make their home in the Mekong, including the giant Mekong catfish and the giant freshwater stingray, as well as the endangered Irrawaddy dolphin.

The scientists estimate that the region’s fish account for almost half of the protein in the diet of the people of Laos and nearly 80 percent for the people of Cambodia. Four out of five households in the region rely heavily on fish for food, jobs, or both.

“Many people in Southeast Asia rely on fish both for food and their livelihood; it’s a huge issue, crucial in the lives of many people. Hydropower is also a critical resource in the region,” said Deng, a PNNL chief scientist and an author of the paper.

“Can we reduce the impact of dams on fish, to create a sustainable hydropower system and ensure the food supply and livelihoods of people in these regions? Can others learn from our experiences in the Pacific Northwest? This is why we do research in the laboratory — to make an impact in the real world, on people’s lives,” added Deng.

The same team of scientists just published a paper in the Journal of Renewable and Sustainable Energy, focusing broadly on creating sustainable hydro in the Lower Mekong River Basin. The paper discusses the potential for hydropower sources in the region (30 gigawatts), migratory patterns of its fish, the importance of fish-friendly technology, and further studies needed to understand hydro’s impact on fish of the Mekong.

Authors of the Fisheries paper include scientists from PNNL, the National University of Laos, and the Living Aquatic Resources Research Center in Laos, the Federal University of São João Del-Rei in Brazil, the University of British Columbia; and from Australia, the Port Stephens Fisheries Institute in New South Wales, the Narrandera Fisheries Centre in New South Wales, and Fishway Consulting Services. PNNL’s work in the area has been funded by the U.S. Army Corps of Engineers, DOE’s Office of Energy Efficiency and Renewable Energy, and AusAid, the Australian Agency for International Development.

Reference: Richard S. Brown, Alison H. Colotelo, Brett D. Pflugrath, Craig A. Boys, Lee J. Baumgartner, Z. Daniel Deng, Luiz G.M. Silva, Colin J. Brauner, Martin Mallen-Cooper, Oudom Phonekhampeng, Garry Thorncraft, Douangkham Singhanouvong, Understanding barotrauma in fish passing hydro structures: a global strategy for sustainable development of water resources,Fisheries, March 2014, DOI:10.1080/03632415.2014.883570.

The canaries of the estuaries

environment, fisheries, research, waterways/wetlands

Apr 152014

Original story by Michael Cavanagh, ABC Rural

They could be described as the canaries of the estuaries.

Oysters used to detect contaminants. Researchers using Sydney Rock oysters show the health of NSW waterways varies dramatically.

Sydney rock oysters – which are not part of commercial operations but selected by researchers – are being used to chart the state of waterways from the Hunter Valley through to the New South Wales/Victorian border.

Results varied from high levels of metals in waters around Wollongong through to a pristine environment around the Clyde River near Bateman’s Bay, on the south coast.

Professor Emma Johnston, from the University of New South Wales, says oysters were ‘significantly stressed’ with damaged cells in the estuaries where there were high levels of metals including copper, lead and zinc.

“These oysters are exposed to all the conditions in the water, just as the canaries were exposed to those in air.

“So if something goes wrong we know that there is a problem in the system, so our oysters are filter feeders.

“So they can filter loads of water every day and if there is a containment in the water, they’ll be exposed to that and they will respond.”

Toxic estuaries in NSW making rock oysters infertile

fisheries, research, waterways/wetlands

Apr 132014

Original story by Nicky Phillips, Sydney Morning Herald

High concentrations of metals in Port Jackson, Port Kembla and Botany Bay are having a major impact on marine life, researchers have found.

Shell shock: Professor Emma Johnston and Dr Katelyn Edge. Photo: Brendan Esposito

Toxic levels of copper, zinc and lead from stormwater or due to past industrial dumping are making Sydney rock oysters infertile, University of NSW scientists say.

”We know there are contaminants in the sediments in some estuaries in NSW but we didn’t know what impact they were having on the marine life living in the water until now,” research supervisor Emma Johnston said.

Contaminated oysters found near Five Dock. Photo: Brendan Esposito

The study of 10 NSW estuaries, the first of its kind to measure the effect of toxins on marine animals rather than just measure the level of contaminants in the water or sediment, suggests the pollutants might also be harming other species.

”There are hot spots of contamination throughout estuaries in NSW and we need to find ways to ameliorate that problem because it is causing ongoing ecological damage,” Professor Johnston said.

Although oysters were a hardy species and could survive in heavily polluted areas, they accumulated contaminants such as metals in their tissues, which made them an ideal ”bio-monitor” to assess the overall health of a waterway, she said.

As part of the study, marine ecotoxicologist Katelyn Edge deployed bags of oysters at 58 sites in 10 estuaries along the coast.

After three months Dr Edge, who conducted the research as part of her PhD, measured the level of contaminants in the sediment on the estuary floor, in the water column and in the tissue of the oysters.

”Where the concentration of contaminant was high in both the sediment and oysters’ tissue we found really high stress levels in the oysters,” said Dr Edge, who published her findings in the journal Chemosphere.

The most heavily contaminated estuaries were Port Jackson, Port Kembla, Botany Bay and the Hunter River in Newcastle, she said.

The Clyde, Port Hacking, Broken Bay, Karuah River and the Wagonga Inlet were the cleanest waterways.

Professor Johnston said the findings were a counter to arguments against remediating contaminated sites because their results showed metals in the sediments were causing problems for animals living above the estuary floor.

”’Just leave it there, it’ll be fine’ is an argument we have heard.”

In waterways such as Sydney Harbour, ferries and boats were constantly stirring sediments and dragging contaminants into the water column, she said.

”There are some locations in Sydney Harbour that are some of the most contaminated in the world and rarely is anything done about it,” Professor Johnston said.

In laboratory studies Dr Edge found high levels of metals inside the oysters’ tissues would rupture structures inside their cells, affecting the ability to reproduce.

Sydney rock oysters, a native species found along the coast from Queensland to Tasmania and South Australia, should be used as a biomarker during future developments or dredging to assess the impact on marine ecosystems.

Novaq, world’s first fish-free prawn food from CSIRO

fisheries, government, research

Apr 122014

Original story by Pip Courtney, ABC News

A team of CSIRO scientists has cracked the holy grail of aquaculture by developing the world’s first fish-free prawn food.

Prawns for sale, prawns have been found to grow up to 40 per cent faster on Novaq. Photo: Matt Brann

The royalties from worldwide licensing deals for the Novaq product will earn the CSIRO tens of millions of dollars.

“The research cost about $10 million. We are very confident that this will generate a return on investment back to Australian taxpayers of many, many times the initial investment,” CSIRO’s Dr Nigel Preston said.

There is intense global interest in Novaq because it solves one of the farmed prawn industry’s biggest problems – its reliance on wild fisheries as a core ingredient in prawn food.

But aquaculture has reached “peak fish”, where demand for wild harvested fish meal now outstrips supply.

Without a solution, soaring world demand cannot be met.

“It is absolutely a critical issue for the global aquaculture industry. There’s no more room to get more wild harvest fish, so we’ve got to find alternatives,” Dr Preston said.

This is really a game-changer. There’s nothing like this that I’ve seen in my career and I may see nothing like this again.
CSIRO scientist Dr Nigel Preston

“A justifiable criticism about aquaculture is the continuation of catching wild fish, grinding them up and feeding to farm fish.”

News of Novaq’s development has caused huge excitement around the world, as many thought a fish-free food was impossible.

“It’s the first really viable solution to not having to use wild harvest fish meal,” Dr Preston said.

Australia’s only producer of prawn food, Ridley, has the licence to make Novaq, and aims to have it on the market by the end of next year.

Industry set to grow with Novaq

Ridley’s Bob Harvey says the industry will be able to flourish when it is no longer reliant on fish caught in the wild.

Ridley is aiming to sell the product to the world’s biggest producer of prawns, Asia.

“There is a world shortage of prawns, there’s an insatiable demand in South-East Asia for them,” he said.

“Once you start getting into South-East Asia, you’re talking millions of tonnes.”

Mr Harvey says the opportunity is worth millions of dollars to the company.

“It’s a long journey now to start to commercialise this, but the prize is significant,” he said.

The Novaq formula is a closely guarded secret, but it is known that the product is based on microscopic marine organisms.

“They are so abundant one would have thought that the world would have paid more attention to them, but their misfortune is to be so small,” Dr Preston said.

Novaq in use at an aquaculture facility. The industry is expected to grow without its reliance on fish caught in the wild. Photo: Landline

“The eureka moment [was] that we should be able to use their abundance, and the fact they are a significant component of the natural diet of prawns at every stage of their life history.”

Marine microbes are at the bottom of the ocean food chain and a decade ago scientists knew little about them.

The CSIRO team’s first breakthrough was working out how to feed and then farm them.

“They are harvested when they are 40 days old. We then de-water the product. We drain it down and filter it and then we harvest the product as sludge or … a mud,” said CSIRO’s Dr Brett Glencross.

“That product is dried before it gets milled and then included in a prawn feed.”

Novaq speeds up prawn’s growth

Novaq has delivered a second breakthrough, with scientists discovering prawns grow up to 40 per cent faster on the fish-free food.

“If you think of that in terrestrial terms, it’s very rare to see,” Dr Preston said.

“If you’ve got a chicken growing 40 per cent faster you’d think something was wrong. It was a surprise.

“This is really a game-changer, there’s nothing like this that I’ve seen in my career, and I may see nothing like this again.”

With farmers able to get more tonnes of prawns per hectare of pond space with the same input costs, the new feed will have a huge impact on profits and productivity.

It’s going to make the animals grow better and bigger … it sounds like the magic cure.
Prawn farmer Matt West

“Farmers can either get their prawns to market 30 per cent faster or they could have a prawn that’s 30 per cent bigger,” Dr Preston said.

Novaq offered more surprises by proving more nutritious than traditional fish-based feeds. Prawns fed the new diet were healthier and more robust.

“There’s opportunities to start lifting carrying capacities in ponds and start to push more animals out, but the thing that excites us more is that growth potential,” said the manager of Australian Prawn Farms Matt West.

Australian Prawn Farms at Ilbilbie, south of Mackay, has 33 hectares of ponds, and hopes to triple production by digging more on adjacent caneland.

Its plans have been hampered by a lack of access to power and tough environmental rules, but Mr West hopes Novaq can deliver an increase in yields without the need to push ahead with the extra ponds.

“It’s going to make the animals grow better and bigger and stronger and more healthier … it sounds like the magic cure,” he said.

Novaq’s arrival is perfectly timed, as supermarkets and customers increasingly demand seafood that is certified as sustainable.

“We as an industry do want to be clean and green, we want to go down more of the sustainability path and this is just one of the little ventures that we can do … it has a sustainability tick,” Mr West said.

Fish next on the CSIRO’s agenda

Dr Preston hopes some of the millions of dollars the CSIRO earns from Novaq royalties will be spent finding the same solution for farmed fish. It is a much bigger market, but it is also more challenging.

“Because prawn feeds have about 25 per cent wild harvest fish meal in their formulation, with fish it’s 40 to 50 per cent, but we do have the germ of an idea as we had for Novaq 10 years ago,” he said.

CSIRO-developed Novaq is the world’s first fish-free prawn food. Photo: Landline

“We assume it’ll probably take 10 years but will be pleasantly surprised if it only takes five.”

Dr Preston says it is crucial the work is done, as the aquaculture industry cannot grow unless it finds an alternative to current feed containing wild caught fish.

“One in two fish that everybody eats around the world is farmed so if we’re going to continue to eat more fish, if we’re going to meet those demands for the world’s ever growing population, then it’s going to be farmed seafood,” he said.

“And if it’s going to be farmed seafood it absolutely needs to be sustainable.

“We need to double fish production in the next 50 years … so we need to come up with some innovation and I think providing Novaq for fish is probably the next step.’ Dr Glencross said.

Landline’s story on the Novaq breakthrough is on Landline on ABC1 on Sunday at noon.

Brainy courage of the rainbowfish

Australian native freshwater species, research

Apr 122014

Media release from Springer

Rainbowfish raised in the wild braver than those bred in captivity, study shows

The boldest black-lined rainbowfish are those that are born in the wild. Also more fearless are those that analyze information both sides of their brains. This is the conclusion of Australian researchers Culum Brown and Anne-Laurence Bibost from Macquarie University, in a study published in Springer’s journal Behavioral Ecology and Sociobiology.

Melanotaenia nigrans, Scotts Ck, Adelaide River. Photo: Gunther Schmida

The preference to analyze and react to information with either the left or right hemisphere of the brain is called cerebral lateralization, and is widespread among vertebrates. Lateralization is seen in the preference of humans or parrots to use one hand or claw over the other or to always turn to the same side when moving around objects.

The researchers first tested wild rainbowfish against captive rainbowfish. They then used a modified version of the mirror test to find out if a fish showed a lateral preference to view itself with either its left or right eye. Levels of boldness were tested by timing how long it took a fish to emerge from a safe hiding place.

Non-lateralized fish that did not analyze information in a specific brain hemisphere were significantly bolder than both left- and right-lateralized fish. This suggests that fear is heightened when primarily processed by a single hemisphere, making lateralized fish less bold. Previous studies have shown that complex tasks are more difficult to perform when information processing is shared between two brain hemispheres. It therefore boils down to a question of speed. A non-lateralized fish in a potentially life-threatening situation must first draw information from both hemispheres, and compare and integrate it before it can make a decision. Strongly lateralized fish, on the other hand, can act more quickly because they only draw on information from a single hemisphere.

If non-lateralized fish process fear-related stimuli comparatively slowly or inefficiently, it may be that the moderating effect of fear is somewhat lessened in comparison to strongly lateralized fish. The researchers think this may result in a reduced level of fear generally, or perhaps the decision to explore is already made before the moderating effect of fear comes into play. Either scenario would adequately explain their observation that non-lateralized fish are bolder than lateralized fish.

The researchers were not surprised that wild fish were significantly bolder than captive-reared fish, as previous work they had done showed that populations that are hunted by predators were braver than those from low-predation areas.

“The similarities between personality and laterality are certainly intriguing and hint at a single underlying function or mechanism,” says Brown. “We suggest that these aspects of personality traits are actually caused by variation in laterality.”

Reference: Brown, C. & Bibost, A-L. (2014). Laterality is linked to personality in the black-lined rainbowfish, Melanotaenia nigrans, Behavioral Ecology and Sociobiology, DOI 10.1007/s00265-014-1712-0

Some of Australia’s remote beaches are the most polluted

community, environment, research, waterways/wetlands, wildlife

Apr 112014

Original story by Jake Sturmer, ABC News

A new study of Australia’s dirtiest and cleanest beaches has revealed some surprising results.

A red-footed Booby on a polluted beach in Australia. Photo: Dr Denise Hardesty, CSIRO

CSIRO researchers have spent two years surveying Australia’s entire coastline, counting rubbish on sections of sand and sea every 100 kilometres.

Australia’s dirtiest and cleanest beaches

NSW

Dirtiest: Shelly Beach, Manly
Cleanest: Red Rock Beach, NSW North Coast

Northern Territory

Dirtiest: Cape Arnhem
Cleanest: Cape Hay

Queensland

Dirtiest: Barney Point Beach, Gladstone
Cleanest: Mackay

South Australia

Dirtiest: Border Village (SA)
Cleanest: Nora Creina

Tasmania

Dirtiest: East Kangaroo Island (West Gulch)
Cleanest: Cape Grim

Victoria

Dirtiest: Pearse’s Road Beach
Cleanest: Gibbs Track Beach, Lakes Entrance

Western Australia

Dirtiest: Ellensbrook Beach
Cleanest: 80 Mile Beach

Source: CSIRO

The survey of more than 175 beaches found the dirtiest beach in Australia was Border Village on the coast between Western Australia and South Australia.

This was typical of the study that found remote and hard to reach beaches were among Australia’s most grotty.

Lead researcher Dr Denise Hardesty says the rubbish did not float in from polluted oceans abroad.

By using ocean current data and examining the items, researchers could tell much of the mess fell from the hands of ordinary Australians.

“In general most of what we find is from us,” Dr Hardesty said.

“No matter how remote you are, how close you are to an urban city, we leave our litter everywhere.”

Illegal dumping, irresponsible mariners and careless beachgoers are all to blame, she says.

Researchers are suggesting increased regulation and enforcement, particularly of illegal dumping.

“We aren’t doing as well as we could, as we need to be doing, in terms of waste management,” Dr Hardesty said.

More than 150 million pieces of rubbish

The CSIRO study estimates more than 150 million pieces of rubbish litter Australia’s sand and shores.

The most common item was plastic following rapid growth in global plastic production.

“More than three-quarters of what we find in terms of rubbish is plastic,” Dr Hardesty said.

This had a disastrous effect on some 600 marine species who then consumed what researchers have termed “plastic food”.

Dr Hardesty said she had found cigarette lighters, toothbrushes, pill bottles and bottle caps in the stomachs of birds.

“We open turtles that have died and see that they’re jammed full of plastics,” she said.

“I’ve found over 200 pieces of plastic in a single bird.”

Communities cleaning up Australia

Retired plastic surgeon John Hanrahan and other former professionals have formed a group to clean up the waters off Western Australia’s sunny Abrolhos Islands.

They visit once a year to clean up the mess left by tourists and fishermen over the decades.

“To me they are unique islands in this part of the world, they’re coral islands, they’re well south of the usual position and it seems to be sacrilege to let them deteriorate,” Mr Hanrahan said.

“I think we all have a responsibility to look after these islands and part of looking after them, in my view, is cleaning up the refuse.

“What I’d like to see is other people take up the cause as it were and say ‘yes all right, we can do a little bit’.”

Migratory shore birds on 80 Mile Beach in Western Australia. Photo: Matt Brann, ABC

A new tiny species of crayfish from eastern Australia

Australian native freshwater species, community, research, threatened species, waterways/wetlands

Apr 102014

News release from Pensoft Publishers

Hidden in one of Australia’s most developed and fastest growing areas lives one of the world’s smallest freshwater crayfish species.

The eastern swamp crayfish Gramastacus lacus sp. n. a new species of freshwater crayfish from coastal New South Wales, Australia.

Robert B. McCormack the Team Leader for the Australian Crayfish Project described the new species belonging to the genus Gramastacus, after 8 years of research in the swamps and creeks of coastal New South Wales, Australia. The study was published in the open access journal ZooKeys.

Being a small crayfish species it has remained undescribed and undiscovered in one of the fastest developing regions of Australia. Only one other species of Gramastacus crayfish is known and it occurs some 900 km away in the Grampians region of Victoria.

This new species is found in lowland ephemeral habitats surrounding coastal lakes and lagoons from Wamberal Lagoon, north along the coastal strip to Wallis Lake. Being dependent on regular natural flooding and drying cycles, only lowland, swampy areas are suitable for this tiny crayfish.

Each crayfish digs a small rounded cross-section burrow up to one metre deep into the water table to survive the drying cycle. Some areas are riddled with these small burrows as they are a very prolific species and can occur in very high numbers in small habitat areas.

The newly described crayfish are found in one of Australia’s most developed regions. Unfortunately, this means that much of their habitat has been lost in the past as these ephemeral areas are the first to be drained or reclaimed to make way for agriculture, industry, housing developments, golf courses, infrastructure, etc. Now, being found and officially described, this crayfish must be considered in any further developments and hopefully future habitat loss will be reduced.

The scattered populations of Gramastacus seem highly fragmented and many are increasingly threatened by a range of risks other than human development. Invasive crayfish, pest fish species like plague minnows and swordtails, rising sea levels and falling water tables all are increasing dangers. Luckily, the large number of National Parks and Reserves along the coastal strip provides safe refuges for some populations.

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About the Australian Crayfish Project

Started in 2005 The Australian Crayfish Project (ACP) is a privately funded project run entirely by volunteers with a thirst for knowledge on freshwater crayfish. We all freely give our time and resources to support the project. Australia has one of the most diverse ranges of freshwater crayfish species on the planet yet there is much confusion with the description and distribution of species and many species remain undiscovered & undescribed. The project is discovering dozens of new species or new populations that were never known to exist. Our aim is to find and identify all species of freshwater crayfish and their habitat, the bottom line is that if no one knows these species are there and they don’t even have a name then how can they be protected and conserved into the future? The results of this project will ensure that all management agencies take the crayfish and their habitat into consideration for future environmental, conservation, development and catchment management plans, etc.

Australia’s unique crayfish are important keystone species which have a disproportionately large effect on the whole catchment relative to their abundance. They play a critical role in maintaining the structure of the whole ecological community, their prosperity and abundance directly affecting the health and abundance of numerous other species (macroinvertebrates, fish, eels, turtles, lizards, snakes, water rats, platypus and birds, to name just a few) in the ecosystem. Please help us help the crayfish and all the other species that rely on them for their survival. http://www.aabio.com.au/the-australian-crayfish-project/

Additional Information

Article under conservation and research Australian Aquatic Biological.

For a full list of all Australian Freshwater Crayfish: http://www.aabio.com.au/crayfish-list/

Original source

McCormack RB (2014) The eastern swamp crayfish Gramastacus lacus sp. n. (Decapoda, Parastacidae) a new species of freshwater crayfish from coastal New South Wales, Australia. ZooKeys 398: 53–67. doi: 10.3897/zookeys.398.7544

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