How Australia’s Outback got one million feral camels: Camels culled on large scale

A new study by a University of Exeter researcher has shed light on how an estimated one million-strong population of wild camels thriving in Australia’s remote outback have become reviled as pests and culled on a large scale.Sarah Crowley, of the Environment and Sustainability Institute at the University of Exeter’s Penryn Campus, explored the history of the camel in Australia, from their historic role helping to create the country’s infrastructure through to their current status as unwelcome “invader.”The deserts of the Australian outback are a notoriously inhospitable environment where few species can survive. But the dromedary camel (Camelus dromedarius) prospers where others perish, eating 80% of native plant species and obtaining much of their water through ingesting this vegetation.Yet for numerous Australians, particularly ranchers, conservation managers, and increasingly local and national governments, camels are perceived as pests and extreme measures — including shooting them with rifles from helicopters — are being taken to reduce their population.In her article, published in the journal Anthrozos, Crowley proposes that today’s Australian camels exemplify the idea of “animals out of place” and discusses how they have come to inhabit this precarious position.She said: “Reports estimate there are upwards of a million free-ranging camels in Australia and predict that this number could double every eight years. As their population burgeons, camels encroach more frequently upon human settlements and agricultural lands, raising their media profile and increasing local animosity toward them.”The camel was first brought to Australia in the 1800s when the country was in the midst of a flurry of colonial activity. The animals were recognized by pioneers as the most appropriate mode of transport for the challenging environment because they require significantly less water, feed on a wider variety of vegetation, and are capable of carrying heavier loads than horses and donkeys.Camels therefore played a significant role in the establishment of Australia’s modern infrastructure, including the laying of the Darwin-Adelaide Overland Telegraph Line and the construction of the Transnational Railway.Once this infrastructure was in place, however, and motorized transport became increasingly widespread, camels were no longer indispensable. In the early part of the 20th century they rapidly lost their economic value and their displaced handlers either shot their wards or released them into the outback where, quite discreetly, they thrived.It was not until the 1980s that surveys hinted at the true extent of their numbers, and only in 2001 that reports of damage caused by camels were brought to the general populace.Camels are not the most dainty of creatures. Dromedaries are on average six feet tall at the shoulder, rendering cattle fencing no particular obstacle to their movement. By some accounts, camels may not even see small fences and consequently walk straight through them.Groups of camels arriving on agricultural properties and settlements in Australia, normally in times of severe drought, can also cause significant damage in their search for water.In 2009, a large-scale culling operation began. There were objections from animal welfare groups and some landowners who were concerned that the method of culling from helicopters, leaving the bodies to waste, is inhumane. Most objectors, however, were primarily concerned that culling is economically wasteful and felt that the camels should be mustered for slaughter or export.There are also concerns regarding the global environment, as camels may contribute to the desertification of the Australian landscape. They are also ruminants and thus produce methane, adding to Australia’s carbon emissions. …

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Threat of hidden crop pest to poorer nations revealed

The abundance of crop pests in developing countries may be greatly underestimated, posing a significant threat to some of the world’s most important food producing nations, according to research led by the University of Exeter.Data on the known distributions of almost 2,000 crop-destroying organisms in 195 countries were analyzed in the first global assessment of the factors determining the distribution of crop pests.Dr Dan Bebber and Professor Sarah Gurr, of Biosciences at the University of Exeter, found that if all countries had levels of scientific and technical capacity similar to the developed world, the number of pests reported would rise greatly and the true extent of the threat would be better understood.Many developing countries are expected to harbor hundreds of unreported crop pests and diseases, based on current levels of agricultural productivity.Around one sixth of the world’s agricultural production is lost to destructive organisms annually, with further losses post-harvest.Crop pests are often introduced by human activities such as trade and travel, with the wealth of a country linked to the number of invasive species recorded there because — whilst growing rich through trade — they have also accidentally imported pests in agricultural produce.But this study also considered the link between the wealth of a country (by per capita GDP) and its ability to detect, identify and report the number of crop pests present.Developing countries are less likely to have the capacity to observe invasive species than affluent, technologically-advanced nations.The researchers used data collated from published literature over many decades by the inter-governmental, not-for-profit organization CABI and made available from its Plantwise knowledge bank.Using GDP and scientific output as indicators of pest detection capacity, the study found that the pest load of the developing world appears to be greatly underestimated, and that this lack of knowledge may be severely hampering crop protection in some of the world’s most important food producing nations.Dr Dan Bebber said: “Crop pests pose a significant and growing threat to food security, but their geographical distributions are poorly understood.””Country wealth is likely to be a strong indicator of observational capacity, not just trade flow, as has been interpreted in previous studies of invasive species. If every country had US-levels of per capita GDP, then on average countries woul d be reporting more than 200 additional pests and diseases. This suggests that enhanced investment in pest observations will reveal the hidden threat of crop pests and pathogens, as well as bring into focus the opportunity to lose less of the crop by appropriate pest control. The first step to solving crop losses is to identify the pests responsible.”The largest numbers of crop pests were reported by the USA, followed by India, China, France and Japan. Island nations reported more pests than coastal and landlocked nations, and the number of pests increased slightly with rainfall.Professor Sarah Gurr added: “This follows hot on the heels of our recent paper showing that pests and pathogens are on the move in the face of climate change. When coupled to this study we can see that many nations are underestimating pest and pathogen loads. Taken collectively, these papers draw attention not only to the threat of crop disease, and thus global food security, but also to our need for more trained pathologists to inform policy.”Story Source:The above story is based on materials provided by University of Exeter. Note: Materials may be edited for content and length.

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The eyes have it: Jackdaw birds use their eyes to communicate with each other

Researchers in Cambridge and Exeter have discovered that jackdaws use their eyes to communicate with each other — the first time this has been shown in non-primates.While what humans do with their eyes has been well studied, we know almost nothing about whether birds communicate with members of the same species with their eyes.The new study, published today in Biology Letters, shows that jackdaw eyes are used as a warning signal to successfully deter competitors from coming near their nest boxes.Gabrielle Davidson of the University of Cambridge, who led the study, said: “Jackdaw eyes are very unusual. Unlike their close relatives, the rooks and crows — which have very dark eyed — jackdaw eyes are almost white and their striking pale irises are very conspicuous against their dark feathers.”While most birds have black or dark brown eyes, bright eyes are not unknown in the avian world, and around 10% of passerines (perching birds) have coloured irises. The question Davidson wanted to answer was do jackdaws use their bright eyes to communicate with fellow jackdaws?Just before the spring breeding season arrived last year, Davidson installed one of four different pictures in 100 jackdaw nest boxes on the outskirts of Cambridge. The pictures were either black (the control), a pair of jackdaw eyes, a pair of jackdaw eyes in a jackdaw’s face, or a jackdaw’s face with a pair of black rook eyes. She then filmed the effect the different pictures had on the birds’ behaviour.”Jackdaws are unique among the crow family in that they nest in cavities in trees. These hollows are natural — the birds cannot excavate their own nest cavities as some woodpeckers do — so they have to compete for a limited resource. And because jackdaws nest in close proximity to each other, they fight a lot to gain the best nesting sites,” she explained. Often what initiates these fights are jackdaws approaching nest boxes that are not their own.After analysing 40 videos of jackdaws peeking into each other’s nest boxes, she found that compared with the other nest boxes, those that contained the picture of a jackdaw with its bright eyes was much more likely to deter the birds from landing on it, and that the birds spent less time near such a nest box.Davidson’s study is the first to show the eyes being used as a means of communication between members of the same species outside primates.”Before now we knew very little about why some birds have brightly coloured eyes. In jackdaws, the pale eyes may function to improve their ability to defend their nest and chicks from competitors. It also raises the question of whether this is unique to jackdaws, or if other cavity nesting birds also use their eyes in a similar way,” she added.Story Source:The above story is based on materials provided by University of Cambridge. …

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Climate change will upset vital ocean chemical cycles, research shows

Sep. 8, 2013 — New research from the University of East Anglia shows that rising ocean temperatures will upset natural cycles of carbon dioxide, nitrogen and phosphorus.Plankton plays an important role in the ocean’s carbon cycle by removing half of all CO2 from the atmosphere during photosynthesis and storing it deep under the sea — isolated from the atmosphere for centuries.Findings published today in the journal Nature Climate Change reveal that water temperature has a direct impact on maintaining the delicate plankton ecosystem of our oceans.The new research means that ocean warming will impact plankton, and in turn drive a vicious cycle of climate change.Researchers from UEA’s School of Environmental Sciences and the School of Computing Sciences investigated phytoplankton — microscopic plant-like organisms that rely on photosynthesis to reproduce and grow.Lead researcher Dr Thomas Mock, said: “Phytoplankton, including micro-algae, are responsible for half of the carbon dioxide that is naturally removed from the atmosphere. As well as being vital to climate control, it also creates enough oxygen for every other breath we take, and forms the base of the food chain for fisheries so it is incredibly important for food security.”Previous studies have shown that phytoplankton communities respond to global warming by changes in diversity and productivity. But with our study we show that warmer temperatures directly impact the chemical cycles in plankton, which has not been shown before.”Collaborators from the University of Exeter, who are co-authors of this study, developed computer generated models to create a global ecosystem model that took into account world ocean temperatures, 1.5 million plankton DNA sequences taken from samples, and biochemical data.”We found that temperature plays a critical role in driving the cycling of chemicals in marine micro-algae. It affects these reactions as much as nutrients and light, which was not known before,” said Dr Mock.”Under warmer temperatures, marine micro-algae do not seem to produce as many ribosomes as under lower temperatures. Ribosomes join up the building blocks of proteins in cells. They are rich in phosphorus and if they are being reduced, this will produce higher ratios of nitrogen compared to phosphorus, increasing the demand for nitrogen in the oceans.”This will eventually lead to a greater prevalence of blue-green algae called cyanobacteria which fix atmospheric nitrogen,” he added.

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US depression treatment demonstrated effective for UK

Aug. 19, 2013 — A US model of treating depression through a network of specialists could effectively be imported into the UK, new research has revealed.Collaborative care involves depressed people having access to a team of specialists, with advice and support often given over the phone. A trial led by Professor David Richards at the University of Exeter Medical School found that collaborative care led to improvement of depression symptoms immediately after treatment. Furthermore, 15 per cent more patients were still improved after 12 months, compared with those who saw their GP.Depression is a long-term and relapsing condition, and is set to be the second largest cause of global disability by 2020. At the moment, treatment for 85-95 per cent of UK cases is through GPs, but the organisation of care in this setting is not optimal for managing depression because of barriers between general and specialist health professionals, patients not taking their medication and limited specialist support for patients. In contrast, collaborative care involves a structured management plan, regular follow-ups with patients and better communication between health professionals. To achieve this, a care manager is appointed to act under the supervision of a specialist, and to liaise between GPs and mental health specialists.The findings of the CADET study are published in the BMJ online today, August 19. The study was funded by the UK Medical Research Council, managed by the National Institute for Health Research (NIHR), on behalf of the MRC-NIHR Partnership. Professor Richards also receives funding from the NIHR Collaboration for Leadership in Applied Health Research and Care in the South West Peninsula (PenCLAHRC).Professor Richards said: “This is one of the largest studies of collaborative care internationally, and demonstrates that it is as effective in the UK as it is in the US, and could reliably be imported. Importantly, patients also told us that they preferred the approach to their usual care. …

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Shifting patterns of temperature volatility in the climate system

July 24, 2013 — In recent decades there has been increased variability in yearly temperature records for large parts of Europe and North America, according to a study published online today (24th July 2013) in Nature.The study was carried out by scientists from the Centre for Ecology & Hydrology, the University of East Anglia and the University of Exeter.Lead author Dr Chris Huntingford from the Centre for Ecology & Hydrology said, “Fluctuations in annual average temperatures have shown very substantial geographical alteration in recent decades. However, to our surprise, when considered across the globe, total variability has been relatively stable.”Co-author Professor Phil Jones, from the University of East Anglia said, “We used globally-complete surface temperature data that has been constructed by merging observations and weather forecasts, and verified our findings against station temperature records”The study concluded that regions of high variability have moved markedly over the last five decades, including to areas of high population in Europe and North America. Dr Huntingford added, “The movement of raised temperature variability to regions of high population may have contributed to the general perception that climate is becoming more volatile.”The study also examined future projections by 17 climate model simulations. Almost all predict that overall temperature fluctuations will actually decrease towards the end of this century, as greenhouse gas concentrations increase.Co-author Professor Peter Cox, from the University of Exeter said, “We provide evidence that decreasing global temperature variability will be a consequence of major sea-ice loss in a warmer world.”Dr Huntingford added, “Our findings contradict the sometimes stated view that a warming world will automatically be one of more overall climatic variation.”Technical note — The analysis looked at year-to-year variability in temperature at different geographical locations. This variability is occurring around general global warming trends. These trends were subtracted from the actual temperature measurements, and the remaining “anomalies” analyzed for changes over time and space.

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Tailoring diabetes treatment to older patients yields dramatic results

July 8, 2013 — More than a quarter of over 70s with type 2 diabetes could benefit simply from improving communication and education in the clinic, new research has revealed. A study led by the University of Exeter Medical School and published in The Lancet found that 27 percent achieved better glycaemic control through individualised care alone.At the moment, patients over the age of 70 are treated using a blanket method of aggressively reducing blood glucose levels, but that does little to take their complex needs into account.Dr David Strain, from the University of Exeter Medical School, who led the study, said: “People over the age of 70 are more likely to have multiple complications, such as heart disease, as well as type 2 diabetes. Yet perversely, these patients have so far been excluded from clinical trials, precisely because of these complications. It means they are generally treated with a ‘one-size-fits-all’ approach. We found that simply by individualising goals and setting realistic targets, then spending time talking to patients rather than aggressively chasing targets resulted in nearly a quarter of patients achieving better glycaemic control, without the need for medication.”Type 2 diabetes is one of the most common chronic disorders in older adults. The number of people over the age of 65 has grown worldwide, and could now be as high as one in five. Older patients are more susceptible to complications caused by hyperglycaemia, when blood sugar levels are not properly balanced. These complications can increase the risk of falls and dizziness.The situation has led to calls for treatment to be individualised, but so far evidence to support the case has been lacking. The research was funded by Novartis Pharma AG, the company that produces the antihypertensive agent vildagliptin. In the study, 139 patients from across Europe were given 50mg of the drug twice a day, while the same number of comparable patients were given a placebo, plus individualised care. …

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Boat noise stops fish finding home

June 28, 2013 — Boat noise disrupts orientation behaviour in larval coral reef fish, according to new research from the Universities of Bristol, Exeter and Liège. Reef fish are normally attracted by reef sound but the study, conducted in French Polynesia, found that fish are more likely to swim away from recordings of reefs when boat noise is added.Sophie Holles, a PhD researcher at the University of Bristol and one of the study’s authors, said: “Natural underwater sound is used by many animals to find suitable habitat, and traffic noise is one of the most widespread pollutants. If settlement is disrupted by boat traffic, the resilience of habitats like reefs could be affected.”Sound travels better underwater than in air and reefs are naturally noisy places: fish and invertebrates produce feeding and territorial sounds while wind, waves and currents create other background noise. Boats can be found around all coastal environments where people live and the noise they make spreads far and wide.Co-author, Dr Steve Simpson, a marine biologist at the University of Exeter, said: “Boat noise may scare fish, affecting their ecology. Since one in five people in the world rely on fish as their major source of protein, regulating traffic noise in important fisheries areas could help marine communities and the people that depend on them.”The study used controlled field experiments with settlement stage coral reef fish larvae. Larvae in a long plastic tube could decide to swim towards or away from a speaker playing back different sounds. In ambient noise equal numbers of fish were found in each section of the tube and in reef noise most fish swam towards the sound. But when boat noise was played along with reef noise more fish swam away from the sound than in reef noise alone.Co-author, Dr Andy Radford from the University of Bristol, said: “This is the first indication that noise pollution can affect orientation behaviour during the critical settlement stage. Growing evidence for the impact of noise on fish suggests that consideration should be given to the regulation of human activities in protected areas.”The research is published in Marine Ecology Progress Series.

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Personality is the result of nurture, not nature, suggests study on birds

June 5, 2013 — Personality is not inherited from birth parents says new research on zebra finches.External factors are likely to play a bigger part in developing the personality of an individual than the genes it inherits from its parents, suggests the study.Researchers at the University of Exeter and the University of Hamburg investigated how personality is transferred between generations. They found that foster parents have a greater influence on the personalities of fostered offspring than the genes inherited from birth parents.Dr Nick Royle from Biosciences at the University of Exeter said: “This is one of the first experiments to show that behaviour can be non-genetically transmitted from parents to offspring. Our study shows that in zebra finches, personality traits can be transmitted from one generation to another through behaviour not just genetics.”The research, published in the journal Biology Letters, measured personality by placing the zebra finches in a new environment and counting the number of features they visited. Some were shy, staying mainly in one place while others explored widely demonstrating a more outgoing personality. Male and female birds were then paired up and allowed to breed. Each clutch of eggs was fostered by another pair just prior to hatching. Offspring personality was measured once they were adults. Offspring size was also measured and was found to be primarily genetically inherited and not significantly influenced by foster parent size.Although this study considers personality inheritance in zebra finches, it raises questions about the inheritance of personality in other species, including humans. Do adopted children inherit the personality characteristics of their birth parents or their adoptive parents? Is the environment more important than genetic inheritance in the development of personality?The results of this study indicate that non-genetic transmission of behaviour can play an important role in shaping animal personality. …

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Coral reefs suffering, but collapse not inevitable

May 9, 2013 — Coral reefs are in decline, but their collapse can still be avoided with local and global action. That’s according to findings reported in the Cell Press journal Current Biology on May 9 based on an analysis that combines the latest science on reef dynamics with the latest climate models.

“People benefit by reefs’ having a complex structure — a little like a Manhattan skyline, but underwater,” said Peter Mumby of The University of Queensland and University of Exeter. “Structurally complex reefs provide nooks and crannies for thousands of species and provide the habitat needed to sustain productive reef fisheries. They’re also great fun to visit as a snorkeler or diver. If we carry on the way we have been, the ability of reefs to provide benefits to people will seriously decline.”

To predict the reefs’ future, the researchers spent two years constructing a computer model of how reefs work, building on hundreds of studies conducted over the last 40 years. They then combined their reef model with climate models to make predictions about the balance between forces that will allow reefs to continue growing their complex calcium carbonate structures and those such as hurricanes and erosion that will shrink them.

Ideally, Mumby said, the goal is a carbonate budget that remains in the black for the next century at least. Such a future is possible, the researchers’ model shows, but only with effective local protection and assertive action on greenhouse gases.

“Business as usual isn’t going to cut it,” he said. “The good news is that it does seem possible to maintain reefs — we just have to be serious about doing something. It also means that local reef management — efforts to curb pollution and overfishing — are absolutely justified. Some have claimed that the climate change problem is so great that local management is futile. We show that this viewpoint is wrongheaded.”

Mumby and his colleagues also stress the importance of reef function in addition to reef diversity. Those functions of reefs include the provision of habitat for fish, the provision of a natural breakwater to reduce the size of waves reaching the shore, and so on. In very practical terms, hundreds of millions of people depend directly on reefs for their food, livelihoods, and even building materials.

“If it becomes increasingly difficult for people in the tropics to make their living on coral reefs, then this may well increase poverty,” said the study’s first author, Emma Kennedy. It’s in everyone’s best interest to keep that from happening.

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