Tuesday, September 27, 2011

Wildlife Bytes 28/9/11

Editorial; An eight-year old girl in Los Angeles has won our WPAA Wildlife Warrior of the Month award. Katie Donaldson asked her friends who were attending her eighth birthday party not to bring presents, but to make a donation to help kangaroos. She sent us the $125 AUD dollars she raised, asking that we use it to help the kangaroos. Thank you very much Katie, and we have sent you a nice birthday present, and the kangaroos thank you too.

Unique Fraser Island Painting for Sale

Wild Beauty of Fraser Island" was specially commissioned by Vegan Warriors and has had visitors to the Australia Zoo Wildlife Hospital in awe, where it has been on display for the past few months. Profts from the sale will go towards Vegan Warriors and the Wildlife Hospital. Vegan Warriors continually campaign against the horrific treatment of dingoes on Fraser Island, land clearing, rodeos, circuses, factory farming and bobby calf starvation. The Hospital takes in and rehabilitates over 8,600 native animals each year, victims of landclearing and disease. Wild Beauty of Fraser Island by Leigh Hutfield is 1.83 metres x 61cm of Acrylic and muslin on canvas. The expanse of golden white sand which strengths the entire length of the east side of Fraser Island – more commonly known as 75 mile Beach; is the scene that is set for my latest painting……Incorporating the dignified yet beautiful Dingo’s that roam this captivating island. The painting is currently for sale on EBay Item No. 280734892834 * For the Animals

Pet Wildlife

Florida has more invasive amphibians and reptiles than anywhere else in the world, and the pet trade is the No. 1 cause, researchers said in a report released Thursday. State officials, meanwhile, confirmed the presence of another type of invasive species -- the giant African land snail -- in South Florida, where it may pose a threat to human health as well as agriculture and even buildings. The 20-year amphibian and reptile study led by University of Florida researcher Kenneth Krysko was published in the journal Zootaxa. It urges the passage of stronger laws to prevent the release of exotic species. "No other area in the world has a problem like we do, and today's laws simply cannot be enforced to stop current trends," Krysko said in a statement. He is herpetology collection manager for the Florida Museum of Natural History on the Gainesville campus. The study says the pet industry was most likely responsible for the introduction of 84 percent of 137 nonnative reptile and amphibian species introduced from 1863 through 2010. That includes 25 percent linked to one importer, Strictly Reptiles of Hollywood. * Keysnet.com
Read more http://www.keysnet.com/2011/09/20/379641/florida-capital-of-invasive-species.html


There are many things you might expect to find if you visited a military base; soldiers, armoured vehicles or even weapons may be high on the list. However, at Defence Establishment Orchard Hills you’d also find more than 1000 kangaroos on site, perhaps a slightly more surprising discovery. “At the last census in November 2010, the kangaroo population at Orchard Hills totalled approximately 1100 animals,” a Defence Department spokeswoman said. “The majority of the kangaroos are in a number of sectioned areas and are considered to be in manageable populations. Development in the vicinity of the Defence Establishment Orchard Hills has not had a noticeable impact on these numbers.” She said a compromise had been reached to enable the work of the base to go ahead without too much interruption. “Defence Establishment Orchard Hills actively manages a sustainable kangaroo population in accordance with the Defence Kangaroo Management Plan, which identifies a number of management options to minimise the impact on operations. “Personnel located at Defence Establishment Orchard Hills are aware of the kangaroo population and advise management of any potential impact or disruption to operations.” *Penrith Press

Purina Pet Foods Boycotted

Wildlife groups are asking pet owners to boycott Purina Pet Foods. Purina (owned by Nestle, we understand) have been running a national advertising campaign stating proudly that they use kangaroo meat in their tinned dog food. Dozens of people have contacted them by phone and email, pleading with them to stop using kangaroo meat. They have all been laughed off. So the wildlife groups have decided to mount a campaign asking pet owners to boycott Purina foods, and not only boycott them, but telling Purina why....by phone or email. Purina contact details are below......

Please contact PetCare Advice Centre on 1800 738 238, or email them at https://www.purina.com.au/Ask-Purina.aspx If you get a poor response, please email them back, dont let them get away with the lies they tell.

Meanwhile, what the Wildlife groups are now doing is determining all pet food brands in Australia that contain kangaroo meat because many do not specify the meat source This may first require a campaign for accurate labelling of meat type in all tinned pet food.. Then we can raise community awareness about issues surrounding the kangaroo industry in association with the pet foods that use its products. More details about the Purina campaign can be found here http://www.kangaroo-protection-coalition.com/boycott-purina.html

Seals to be Killed

Two of Canada's leading marine biologists and a conservation group say a five-year proposal to slaughter 140,000 grey seals in the southern Gulf of St. Lawrence is being driven by politics, not science. "I don't support it," said Hal Whitehead, a professor at Dalhousie University in Halifax who specializes in the study of whales. "From what I've seen of the rationale, it doesn't make much sense to me." Earlier this month, a federal advisory panel urged Fisheries Minister Keith Ashfield to approve the cull, which would result in the killing of 70 per cent of the grey seals that feed in an area that stretches from Quebec's Gaspe Peninsula to the east side of Cape Breton. The Fisheries Resource Conservation Council, made up of scientists and fishing industry representatives appointed by the minister, said the proposed cull is an experiment that will test indirect scientific evidence suggesting grey seals are impeding the recovery of cod stocks. Wayne Stobo, a retired researcher with the federal Fisheries Department, said his extensive fieldwork with grey seals has led him to the conclusion that the proposed cull is worth a try. While he doesn't disagree with the professors' arguments, he insisted that experiments don't need control groups to be valid. "The nature of an experiment is that you try something and see what the result is," he said, adding that scientists didn't need a control group to conclude that the collapse of the cod stocks in the early 1990s was largely due to overfishing. * CTV News
Read more ... http://www.ctv.ca/CTVNews/SciTech/20110925/seal-cull-proposed-criticism-110925/

Exotic Carp

The east coast floods last summer flushed much needed water through the Murray Darling River system. But with higher water levels the carp are breeding like rabbits, according to locals. The New South Wales Department of Primary Industries and Fisheries says in the latest breeding season carp numbers have increased more than 4,000 per cent in the lower Darling River below Menindee. *WPAA


Two new studies have revealed how some frogs can survive the chytrid fungal disease that is currently devastating amphibian populations worldwide. Known as chytridiomycosis, the disease is caused by the fungus Batrachochytrium dendrobatidis (Bd), and is more prevalent in some frog populations than others. To understand why, Dr Kelly Zamudio and PhD candidate Anna Savage, Cornell University in New York examined lowland leopard frogs. They looked for a genetic difference within a key part of the immune system, known as the major histocompatibility complex (MHC). Their results appear this week in the Proceedings of the National Academy of Sciences. MHC proteins act as signposts, alerting the immune system to the presence of a pathogen, which then triggers an immune response to clear the infection. Similar to a lock and key, MHC proteins can only recognise certain pathogens. *ABC Read more ... http://www.abc.net.au/science/articles/2011/09/27/3326532.htm

Dugong Hunting

More traditional owners' groups in north Queensland have agreed to stop hunting dugongs and turtles to let the two species recover from the effects of disastrous floods. Queensland Environment Minister Vicki Darling today said the Girrigun Aboriginal Corporation, which covers two clan groups in the Townsville region, had agreed to suspend hunting of both species indefinitely. The clans are entitled to hunt both species under the Native Title Act but agreed to stop after widespread flooding across Queensland last summer damaged seagrass beds - the major food source for both animals - along the coastline. The agreement comes two weeks after traditional owners' groups from Bundaberg to Gladstone agreed to self-imposed bans on hunting both species. "I think this move speaks volumes about the capacity of local traditional owners' groups to make their own informed decisions about cultural practices that have existed for thousands of years," Ms Darling said in a statement today. "I congratulate the clans of Girrigun for this decision because it acknowledges that, while there are severe limitations in addressing the food supply crisis hitting turtles and dugongs, we can address the impacts humans are having on the population and hunting is one of them." *AAP

Ed comment; But what about the other hunters who dont or wont abide by clan rule? What about some hard Legislation to stop the hunting altogether?


Wildlife rangers have begun relocating 50 rampaging elephants back to the renowned Maasai Mara game reserve to stem rising human deaths and property destruction in outlying villages. On Thursday, the first four of the elephants, due to be relocated over the next 10 days, were shot with tranquilliser darts from a helicopter near Narok, about 150 kilometres south of the capital, Nairobi, a notorious zone for human-wildlife conflict.
Once the giant animals lost consciousness, conservationists carefully winched them up by crane onto trucks for the journey to the Maasai Mara, from where they had been cut off by widening settlement, increasing farming and deforestation. "The greatest challenge to Kenyan wildlife conservation today is Kenya's population growth," said the Kenya Wildlife Service director, Julius Kipng'etich. Workers splashed the elephants with water to cool them before giving another injection to wake them up, ready for their 150-kilometre truck journey to the Maasai Mara. If the operation is a success for the first 50 animals, wildlife service plans to move 200 of them. * AFP


Report says some albatross, petrel and shearwater species nearing extinction as fleets failing to implement simple measures. Up to 320,000 seabirds a year are being killed worldwide each year by being caught up in fishing lines, according to a study being presented to the World Conference on Marine Biodiversity on Tuesday. Some species and populations of albatross, petrels and shearwaters are being pushed to the edge of extinction because many fishing fleets are not taking simple measures to prevent birds chasing bait, experts will warn. Some fleets have drastically cut the carnage though methods such as bird-scaring lines and weighting of hooks. But others are failing to monitor the problem or implement steps that could reduce the problem to "negligible proportions", according to authors of a study that is attempting to set a global baseline against which progress could be measured. * Guardian Read more ... http://www.guardian.co.uk/environment/2011/sep/26/fishing-boats-killing-seabirds

Kangaroos and Bushfires

Bushfires in Central Australia are being blamed for causing native animals to come down with pneumonia. As two bushfires burn out of control north of Alice Springs, sending smoke across the town, wildlife carers have said native animals are being affected. "This is something we haven't seen before," said Cynthia Lynch from Alice Springs Wildcare Inc. She said there has been more bushfires this year than in the past and the smoke was far more noticeable and had been harming native animals. Ms Lynch said she had seen about half a dozen young red kangaroos affected by pneumonia, a disease she had never before witnessed in them. "They are very wheezy and you can hear their chests without a stethoscope," Ms Lynch said. She said all the joeys that were affected over the past six weeks had been hand-raised and were in captivity. It was difficult to know whether those in the wild were unaffected by the condition because they could better escape the smoke, or if wild kangaroos had pneumonia that was undiagnosed, she said. Her comments came as Bushfires NT director Steve Sutton warned two fires were burning out of control north of Alice Springs. Mr Sutton said one fire was burning about 70km north of Alice Springs at Yambah and another was 30km from the town, at Bond Springs. "Currently a lot of smoke is blowing into Alice Springs," Mr Sutton said. *Weekly Times


The annual Humpback whale migration begins in May as the mammals make their way up the West Australian coast from the food-rich Southern Ocean to breeding grounds in warm northern waters. But, experts say an increasing number are not surviving the journey. Of the 14 Humpback whales to die along WA's coast already this season, most have been young. Recently, a dead calf washed up at Gnarloo on the southern end of the Ningaloo Marine Park. The Department of Environment and Conservation's senior wildlife officer Doug Cochrane says the calf at Gnarloo, and others like it, are showing signs of malnutrition. "They are skinny and sickly, they don't have a lot of blubber and it looked like most of them hadn't had a chance to feed from their mothers," he said. Mr Cochrane says there has been a marked increase in sick and dying Humpback whales in recent years. "There's definitely a lot more than say, 10 years ago." Mr Cochrane says conversely, the reason for the increase in deaths could also simply be because of a growing population. "The population is the healthiest recovering Humpback population globally," he said. "So, the same as with all other populations of whatever they be, mammals, birds, or even humans, when you have an increase in population, you also have an increase in losses or deaths." *ABC Read more ... http://www.abc.net.au/news/2011-09-26/humpback-whale-stranding-feature/2943026

Tasmania is set to become a whale-watching mecca over the next few weeks as the world's biggest marine mammals move down the coast and stop here on their way to Antarctica to feed. This week whales have been spotted at Taroona, Binalong Bay and Wineglass Bay and a southern right whale mother and calf have been spotted by eco-tourism operators near Tasman Arch. Tasman Island Adventure Cruises Skipper Craig Parsey said his team recorded 150 whale sightings last year and it looked like 2011 could be an even better whale watching season. "Already we have been told that good numbers of humpback whales are heading down the coast," Mr Parsey said. "With the abundance of krill around the Tasman Peninsula, we are expecting some exciting interactions." He said thousands of dusky dolphins also had been seen playing in local waters. The dusky dolphin was known for its remarkable acrobatics but had commonly been caught in gill nets in the past. *Mercury
Read more ... http://www.themercury.com.au/article/2011/09/28/264801_tasmania-news.html

A record number of whales migrating down the coast has thrilled Hervey Bay whale watch pioneer Brian Perry - but it has him concerned as well. With an increased number of whales passing through, the risk of hitting one of the ocean giants is increasing as well and he is urging caution to all heading out into the waters of Hervey Bay, especially when there is fog or in the night. "Unfortunately accidents can happen," he said. More than 16,000 whales are making their way up the coast of Australia and there have been several collisions between whales and boats so far this year. Mr Perry said there were several hundred whales passing through Hervey Bay at the moment, some of the best numbers seen in years. When Brian and his wife Jill first started their business in 1987, the first of its kind in Australia, they saw about 100 whales in one whole season. Now he said it wasn't unusual to see about 100 whales in a day. Mr Perry said it was heartening to see whale numbers improving. "It's one of the best seasons we've had in 25 years," he said. With people coming from around Australia and the world to visit Hervey Bay this whale watching season, Mr Perry said it was fantastic to see the reactions of people who hadn't had the chance to see whales up close and personal before. A rare sighting of a southern right whale and its calf also excited visitors. It stayed in the area for two or three weeks, which Mr Perry said was "very unusual". *Fraser Coast Chronicle

Red Spot Disease in Fishes

An endemic disease found in fish samples taken to discover what was killing fish in The Narrows and Gladstone Harbour has not been found in Rockhampton waters. Red spot, a disease found in fish all over Australian coastal waters and in Asia, was evident in test samples taken during the current ban on fishing in Gladstone. A spokeswoman for Biosecurity Queensland said the disease was typically caused by a fungus, Aphanomyces invadans, and occurred in fish when they were under stress. The red spot disease, Epzootic ulcerative syndrome, develops as red spots that develop into ulcers, which can cause death in fish. It has been found in estuarine fish including bream, mullet, whiting, eels and catfish. The disease has also been found in freshwater fish farms as well as inland freshwater rivers. While research has found links between highly acidic waters and the red spot disease, no such connection has been made in investigations to the latest outbreak to date. Government investigations have also not found any particular environmental "stressor" in the Gladstone Harbour area that may have caused the recent outbreak. Authorities were still investigating an unknown parasite found in fish samples last week that may have also been contributing to fish deaths in the area.
The government spokeswoman said: "These initial test results identified two conditions, red-spot disease and a parasite. More research is needed into the parasite, which affects the eye of the fish. "Additional testing is being conducted on newly received samples of other fish species, prawns and mud crabs but results are not expected for several weeks. "As further testing and research is still under way, it is too early to determine what is causing the conditions affecting some locally-caught fish." *Bulletin

The State Government has refused to stop Gladstone's massive dredging program while scientists work out what has caused disease in its fish. Yesterday, Greens environment spokeswoman Larissa Waters called for a dredging ban, saying it was wrong that a major environmental crisis was occurring while 46 million cubic metres of dredging works for the liquefied natural gas industry continued unabated. Fisheries Minister Craig Wallace said he would not stop the work because Health Department and independent tests showed no link between dredging and the diseased fish. Mr Wallace - who was in Gladstone for crisis talks with fishermen and the city's port authority - said a taskforce looking into the issue would be headed by Australian Institute of Marine Science chief Ian Poiner. The Government last week banned fishing for about 500sq km - centred on Gladstone's harbour - while scientists try to resolve issues that have shut down part of the region's $40 million commercial fishing industry. Tests have found fish are infected with red spot disease and a parasite that causes milky eye in barramundi. Red spot also broke out in Moreton Bay after the January floods.

Gladstone also has recorded more than 100 turtle and dugong deaths this year, raising concerns of links between the dredging in the Great Barrier Reef World Heritage Area and stressed animals. Senator Waters said that, in August, she had asked Federal Environment Minister Tony Burke to suspend dredging but nothing had happened. "What will it take for the Government to place the long-term health of our precious marine ecosystems and coastal communities ahead of short-term private LNG profits?" she asked. "Dredging is blanketing seagrass beds with sediment and exacerbating poor water quality, making fish susceptible to disease. It's also possible dredging is stirring up organic toxins and heavy metals . . . Everyone is responding to this crisis except for the industry which may be contributing to it . . . and the Government which is allowing them to operate with impunity." Mr Burke said 52 conditions had been imposed on dredging in Gladstone harbour and the department had been monitoring these criteria. *Courier Mail

Barrier Reef Contaminated

A commonly used farm chemical has been found in a Great Barrier Reef catchment at levels an alarming 50 times higher than those considered safe. Diuron is found in more than 100 products and is primarily used in sugar cane, cotton and weed spraying and in anti-fouling paints. A newly released State Environment Department study found the highest readings in Barratta Creek, a popular fishing location about 50km south of Townsville in north Queensland. Penalties for oil spills are increasing, see page 10 of today's print edition of The Courier-Mail. Farm chemicals metolachlor and atrazine were also found at 11 sites, all of which flow into Great Barrier Reef waters. It's the third environmental contamination incident in days, with a major study last week finding poisonous industrial pollutants such as DDT, dioxins and PCBs in birds' eggs in Brisbane and fishing being banned at Gladstone due to diseased fish. WWF-Australia seized on the diuron research, saying it was evidence the Australian Pesticides and Veterinary Medicines Authority was too slow to act.
Spokesman Nick Heath said while the APVMA had been investigating diuron for nine years, eight of the sites investigated were being contaminated at toxic levels.

"This paper (Environment Department) is the smoking gun," he said. "Here we have clear evidence that at least three chemicals which are approved for sale, one of which is known to cause cancer, are present in the Great Barrier Reef environment and in our internationally recognised wetlands, at unacceptably toxic levels." The study found that diuron, which is poisonous to some marine plants and animals, accounted for 97 per cent of the toxicity in Barratta Creek, between Mackay and Townsville. APVMA spokeswoman Felicity McDonald said it had been proposed in July to suspend most diuron uses, but manufacturers and growers had to be given an opportunity to respond and the Environment Department paper would be taken into account. Ms McDonald said atrazine was detected marginally above recommended levels at only one site and the APVMA was confident it could be used safely. "At present, we hold no concerns about the continued use of metolachlor, provided it is used in accordance with conditions outlined on product labels," she said. "Claims that diuron, atrazine and metolachlor are carcinogenic are incorrect and alarmist." Mr Heath said he accepted the APVMA would probably ban diuron, but he was disappointed about further delays. *Courier Mail

Senate Inquiry Backs Away From Koala Protection

Speed limits should be lowered, wild dog controls tightened and research funding boosted to stop the decline of koala numbers, a Senate committee has recommended. But it has stopped short of suggesting the marsupial be added to the threatened species list, saying it is not qualified to pass judgment. Following a 10-month investigation, the Senate's environment committee today delivered 19 recommendations to halt what it says is a nationwide decline in koala numbers. They include getting the government to boost funding for research and koala monitoring, implementing an independent review and acting on the potential threats of wild dogs and koala-unfriendly roads. The committee said there was no question koala numbers were falling but the issue was much more complex than that fact alone. For instance, in some areas in Queensland the koala population is in sharp decline, but in other parts of Australia their numbers have to be managed because of over-population.

Koalas faced a range of threats, from dogs, cars and diseases to issues affecting their habitats, such as climate change. The Senate's investigation is not the first time the koala has come under scrutiny, with the government's chief advisory body on threatened species having considered it no fewer than three times since 1996. From the information it received, the committee said there was a clear need for early conservation work. Environment Minister Tony Burke is considering whether to list the koala as a nationally threatened species and said he welcomed the new information. He noted the government had already spent at least $6.3 million on koala conservation efforts during the past 15 years. "Koalas are an iconic Australian animal. They hold a special place in the hearts of Australians," he said. *AAP

Kangaroo Fence

A higher kangaroo-proof fence will be built around the Hanging Rock racetrack to keep the animals from interrupting future race meetings. This year's traditional Australia Day meeting was cancelled due to kangaroos jumping over fencing and entering the track. Stewards halted racing twice during the event but cancelled the remainder of the card after they declared it too dangerous to continue. A working group then started work on finding a solution whereby kangaroos could still utilise the Hanging Rock Reserve but would be kept off the track. The group approved a final kangaroo management plan, which includes building permanent fences about 1.9 metres high around the track. They replace the existing fences, which are more than 20 years old, and are about 1.5 metres in height, with some parts already 1.8 metres. The fences will also feature a gate to allow wildlife to return to the racecourse after meetings.

Kyneton and Hanging Rock Racing Club general manager Mark Graham described the outcome as a win for racing and the area's kangaroo population. He said racing and wildlife would continue to share the racecourse. "We have successfully shared the racecourse with the local kangaroo population for the past 125 years, apart from a couple of safety issues arising in the past couple of years. 'We were very keen to achieve an outcome which allowed this to continue while ensuring racing can be conducted safely. "The club appreciates the efforts of the working group to find a balanced outcome and for the funding assistance provided by the state government via the Department of Sustainability and Environment, Macedon Ranges Council, Racing Victoria and Country Racing Victoria." The Australia Day event at Hanging Rock is the only race meet held at the picturesque location each year. Northern Victoria MP Donna Petrovich, a member of the working group, said they had found a "timely, practical, cost-effective solution" to the problem. "Hanging Rock races are an important part of the Macedon Ranges from a social, economic and historical perspective. "It was a very positive experience... dedicated to finding a workable outcome for all parties which will enhance and preserve the history of racing at Hanging Rock and also protect the natural environment of this beautiful place and its native wildlife." *Macedon Ranges Weekly


Spiders known for a flesh-eating venom may hold the key to a cure for chronic pain, new research shows. Scientists believe some spiders and their highly toxic venom have emerged as the latest, albeit unlikely, ally in the fight against human illness, inflammation and even erectile dysfunction. They are also investigating spider venom for its potential as a potent bio-insecticide to protect valuable food crops. Scientists at the University of Queensland have been working to harvest venom from some of Australia's deadliest creatures - including spiders, snakes, scorpions and box jellyfish - for bio-medical research. Dr Mehdi Mobli, of UQ's Institute for Molecular Bioscience, will today present his latest findings at ComBio 2011 in Cairns, the nation's peak annual conference for biochemists and molecular biologists. "From the unlikely source of spider venoms, we are working on finding new ways of protecting our food source and crops as well as new therapeutics against pain," Dr Mobli told The Courier-Mail. His research involves the American hobo spider, a distant cousin of the Australian funnelweb, often blamed for a bite that turns necrotic and eats away human cells, tissue and flesh. "Spiders have evolved a biochemically complex venom that is designed to rapidly subdue prey," Dr Mobli said. His research found the potent insecticidal neurotoxin, linked to an ancestral gene, had evolved over 200 million years. "Because it targets the nervous system, it may have benefits for treating nervous system disorders like chronic pain," he said.

He said an Access Economic Report (2007) estimated the economic impact of persistent pain in Australia at about $34 billion a year. "We think primarily it may be useful as a commercial insecticide, where we put this gene into plants so they can protect themselves against pests," Dr Mobli said. "The American hobo spider is the first toxin in spiders that we have been able to track down the ancestral gene. "In this case, it turned out to be a hormone involved in - amongst other things - moulting. "The spiders seem to have recruited this hormone, and then massively changed it to make it exceptionally insecticidal (so it no longer functions as a hormone)." Huge advances in technology in recent years have allowed unprecedented access to molecular diversity of animal venoms - developing a pipeline in venom-based drug discovery. "We have been able to insert a gene encoding this toxin into bacteria, so that we can produce large quantities of the toxin in the bacteria. "We are able to produce large amounts of this toxin for insecticidal testing." *CM


Scientists believe they have identified the tipping point of overfishing that could save the world's coral reefs. They identified the stages or "thresholds" a coral reef eco-system goes through before collapse. And they found how many fish it takes to make a healthy or dying reef. "Hard coral cover is the last line of defence before a reef collapses," said Townsville-based Nick Graham, of the ARC Centre of Excellence for Coral Reef Studies. "But it starts dying when the nuts and bolts go. You see patches of weeds replacing coral, you see more sea urchins devouring the coral, you see a general decline in the species richness on the reef, and you see less coral cover." Dr Graham was part of an international team that surveyed 300 reefs in the Indian Ocean off the east coast of Africa. They found that in well-protected areas there were typically 1000kg-1500kg of fish a hectare of coral reef.

As this is reduced below 1000kg, early warning signs such as increased seaweed growth and urchin activity began to show, Dr Graham said. "It shows us multiple tipping points," he said. "There is more than one line between life and death for a reef." When fish stocks dropped below 300kg/ha, the reef was in real trouble, Dr Graham said. The loss of hard corals, which had been thought of as a warning sign, was actually the last stage in the collapse of a reef, the study found. The researchers found between 300kg-600kg of fish a hectare was the "maximum sustainable yield". As debate rages over the impact of climate change on the Great Barrier Reef, Dr Graham said measuring the amount of fish was a tangible variable. "It is easier to comprehend than some variable like the amount of phosphorous in the water," he said. "Fishermen and scientists have long wondered how many fish can be taken off a reef before it collapses. This sets a target. "The consequences of overfishing can be severe to the ecosystem, and may take decades to recover, but hundreds of millions of people depend on reefs for food and livelihoods, so banning fishing altogether isn't a reality in many nations." The report, "Critical thresholds and tangible targets for ecosystem-based management of coral reef fisheries", has been published in Proceedings of the National Academy of Sciences of the USA (PNAS). *Courier Mail