Livestock grazing effects on sage-grouse

sage_grouse.jpg
(USGS; 21 March 2017)

Effects of livestock grazing on greater sage-grouse populations can be positive or negative depending on the amount of grazing and when grazing occurs, according to research published today in Ecological Applications. The research was conducted by scientists from the United States Geological Survey, Colorado State University and Utah State University.

Higher levels of grazing occurring early in the growing season – that is, before peak plant productivity – was associated with declining sage-grouse population trends, whereas similar levels of grazing that occurred later in the growing season corresponded with sage-grouse population increases. The study authors noted that this finding might reflect the sensitivity of some grass species to being grazed upon during their spring growing period, as well as the potential for additional plant growth if grazing later in the season removes dead vegetation.

“Increasing our understanding of how the amount of grazing and season of livestock use affect vegetation could help inform short-term modifications to livestock management to benefit sage-grouse populations and help sustain western ranching operations,” said Cameron Aldridge, a CSU professor, USGS collaborator and study coauthor.

Studies demonstrating a link between grazing and sage-grouse population trends have been lacking for this landscape species, which use vegetation consumed by livestock for food and shelter. In this new study, scientists analyzed grazing records from Bureau of Land Management allotments from 2002 to 2012 in sagebrush-dominated rangelands across Wyoming to determine the amount of grazing and when livestock graze in the plant-growth season. They then used annual counts of male sage-grouse from 743 breeding sites, known as leks, during the same period to evaluate whether livestock grazing management actions corresponded with sage-grouse population trends.

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Non-breeding ravens live in highly dynamic social groups

(Physorg; 23 march 2017)
Ravens have impressive cognitive skills when interacting with conspecifics – comparable to many primates, whose social intelligence has been related to their life in groups. An international collaboration of researchers led by Thomas Bugnyar, Professor at the Department of Cognitive Biology, University of Vienna, could uncover for the first time the group dynamics of non-breeding ravens. The results help to understand the evolution of intelligence in this species and were published in the scientific journal Scientific Reports

Several recent studies have revealed that ravens are among the most intelligent species of birds and even species in general. But which factors caused the evolution of intelligence? According to a common hypothesis life in social groups can drive brain evolution especially when individuals benefit from remembering the identity of conspecifics and the interactions with them. With such knowledge, animals can avoid conflicts with higher ranking group members or develop alliances to gain better access to resources.

Researchers around Thomas Bugnyar in Austria and colleagues in France outfitted around 30 ravens with little “backpacks,” which measured with GPS the position of the animal every hour. The devices were charged with solar power and the data were transmitted using the GSM network for mobile phones. During the last four years of data collection movements up to 160 kilometers per day were observed. In addition in Austria and Italy a total number of 332 ravens have been marked individually with colored rings and wing-tags and their presence patterns in two study sites were monitored over years.

Conclusion of the biologists…….

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Research work on peregrine falcons inspires future aircraft technologies

Research work on peregrine falcons inspires future aircraft technologies
(Physorg; 23 ;March 2017)

Scientists at BAE Systems and City, University of London have revealed how research work on how falcons fly is inspiring new technologies for aircraft that could contribute to their safety in the air, aerodynamics and fuel efficiency. The technologies could be applied within the next 20 years.

The scientists have developed several concepts following research into how the peregrine falcon – the world’s fastest bird – is able to stay in control and airborne at speeds of up to 200mph, even in high winds. The technologies being developed include ‘sensory feathers’ – 3-D-printed polymer ‘hair’ filaments which would act like sensors on the body of an aircraft, providing an early warning system if it began to stall. Similarly, more densely packed passive polymer filaments may also be capable of changing the airflow very close to the surface of the aircraft which could reduce ‘drag’ on the aircraft wing-skin. Aerodynamic drag ultimately slows aircraft in flight.

A further technology has been inspired by the falcon’s ability to stabilise itself after swooping or landing by ruffling its feathers. Small flexible or hinged flaps on an aircraft could allow the wing to manoeuvre quickly and land more safely at lower speeds. The added safety margin gained using this approach could allow future aircraft of a more compact design or to carry more fuel. In addition, the research so far has shown that the flaps could potentially lower aircraft noise pollution.

Professor Christoph Bruecker from City’s Aeronautical Engineering department, said: “The peregrine falcon is the world’s fastest bird, able to dive for prey at incredibly steep angles and high velocities. The research work has been truly fascinating and I am sure it will deliver some real innovation and benefits for the aerospace sector.”

Professor Clyde Warsop, a specialist in Aerodynamic Flow Control from our military aircraft business based at Filton in Bristol and Warton in Lancashire added: “Working with Professor Christoph Bruecker and his team at City, we’ve investigated how we could apply the unique abilities of the peregrine falcon to aircraft. Bio-inspiration is not a new concept; many technologies that we use every day are increasingly inspired by animals and nature.”

A light of hope for seabirds

albatross.jpg(Francisco González Táboas & Leo Tamini; 21 march 2017)

A new light of hope opened last week for large seabirds when Argentina established the use of measures to prevent its death in fisheries.

The days are not easy in the South Atlantic. Life is hard on the ship. The bad weather, the waves of several meters of height and the constant movement make the tasks of the sailors more difficult. The days, weeks and months away from the families accumulate and make the mainland a very coveted good. However, most of these men – and women – on board love the sea. They love their fish, which give them work and livelihood to live. And they love birds too. The immense and impressive albatrosses and petrels are, along with dolphins and whales, faithful companions of the days on the high seas.

And there are a few times when they have to kill or sacrifice some of these birds, which are caught in the dragging cables of the nets. In fact they are many. It is estimated that every year between 9,000 and 18,000 black-browed albatrosses Thalassarche melanophrys die on only thirty Argentine freezer vessels fishing for hake.

With the help of the Albatross Task Force Argentina of Aves Argentinas (BirdLife in the country), boat workers have learned to recognize and identify each species: the black-browed mollymawk Thalassarche melanophris, the Daption capense petrel, the Southern giant petrel Macronectes giganteus, the white capped albatross Thalassarche cauta, the Southern royal albatros of the south Diomedea epomophora and, of course, the king of the seas, the wandering albatross Diomedea exulans, among others, are part of the varied avifauna of those icy Seas.

Each death of one of them hurts. However they have also learned that things can be done to prevent these birds from dying while fishing.…..

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Watch Thousands of Sandhill Cranes Lift Off From the Platte River at Sunrise

(Meaghan Lee Callaghan 21 March 2017)
To hear America’s “greatest migration,” you have to beat the sunrise. It starts with a single kar-r-r-roo in the dark, before swelling into a crescendo of 80,000 Sandhill Cranes that fills the Platte River by dawn. It’s an impressive spectacle, says Bill Taddicken, the director of Audubon Nebraska’s Rowe Sanctuary. “This is real. I wish more people would get out and experience it.”

In a new video by Vuz TV, Taddicken narrates this poetic scene of the Sandhills, which use the sanctuary and surrounding river valley as a rest stop during their annual migration. The footage shows large, sweeping views of flocks lifting off from the riverbank after feeding on insects and aquatic plants. But while Sandhill Crane populations are largely stable across North America, they’re vulnerable to habitat loss in vital migration spots such as the Platte River. And they’re climate threatened, according to Audubon’s climate report.

Audubon Nebraska is working to preserve the Platte ecosystem and the heritage of the cranes. It’s restoring the river to its historic state by clearing sandbars and soil buildup, and keeping invasive species like phragmites at bay. Moreover, Rowe Sanctuary is preserving the region’s prairie habitat—where Sandhills and other birds love to forage—by mimicking natural processes through prescribed burns and grazing techniques. All this work has clearly had a positive impact, as the Cranes return in the tens of thousands every year.

Endangered ibises benefit from joining egret flocks

(ScienceDaily, AOS; 22 March 2017)

Birds benefit from flocking together — even when they’re not of a feather. According to a new study in The Auk: Ornithological Advances, China’s endangered Crested Ibises benefit from joining forces with other, more visually-oriented bird species while searching for food.

Joining mixed-species flocks can reduce birds’ risk of predation while boosting their foraging opportunities, but it can also expose them to competition and disease, and little research has been done on what this means for birds such as ibises that rely on their sense of touch to find food. Yuanxing Ye and Changqing Ding of the Beijing Forestry University and their colleagues studied the behavior of Crested Ibises foraging with and without Little Egrets in central China’s Shaanxi Province, recording the birds’ behavior with a digital video camera to determine whether they picked up on social cues from the other species. They found that ibises in mixed-species flocks became alert to threats sooner, suggesting they felt less at risk when mingling with the more visually-oriented egrets.

Crested Ibises were once believed to be extinct in the wild, until seven birds were discovered in a remote area of China in 1981. Ye and his colleagues believe this new information about their foraging behavior could benefit ibis conservation. “Developing habitat conditions that favor mixed-species flocks may reduce the perception of risk by ibises due to the early warning effects of egrets, particularly in habitats with high levels of predation or disturbance,” according to Ye.

“Mixed-species flocks are a common occurrence in birds, but little is known about the costs and benefits of joining such groups when species differ in their foraging tactics,” adds the University of Montreal’s Guy Beauchamp, an expert on group living in birds. “In this case, ibises benefitted from joining another more visually-oriented species in that they detected threats more quickly. This study shows how detailed behavioral observations can help us understand why species forage in groups and also join other species.”

Research teaches machines to decipher the dawn chorus

(Author: Physorg; Photo: Wikipedia; 20 March 2017)

Innovative research looking at the timing and sequence of bird calls could provide new insight into the social interaction that goes on between birds. It will also help teach machines to differentiate between man-made and natural sounds and to understand the world around them.

The work is being led by Dr Dan Stowell, a research fellow in machine listening at Queen Mary University of London (QMUL). It is supported through an Early Career Fellowship from the Engineering and Physical Sciences Research Council (EPSRC). An audio slide-show Deciphering the dawn chorus on this research is available on YouTube with examples of the bird recordings.

In August 2015, Dr Stowell’s technology was released to the public in a smartphone app called Warblr. Users record the sound of a bird on their mobile device and the app analyses the sound, matches it with patterns of bird calls in its dataset and provides a list of possible species that the recording matches.

Dr Stowell is now building on this work to take the computer analysis of the sounds that birds make to a new level, to discover more about what messages are being communicated and who is dominating the conversations that are going on.

“Traditionally you would take explicit measures of things like how long is this sound, what frequency is that sound?” says Dr Stowell. “To go beyond this we use modern machine-learning methods where you don’t necessarily know how a computer has made a decision about a particular sound, but by training it, which means showing it lots of previous examples, we can encourage a computer algorithm to generalise from those.”

At the University’s laboratory aviary, female zebra finches provide Dr Stowell with plenty of audio examples for his work.

“We have put the timing of the calls together with acoustic analysis of the content of the call, for instance whether it is a short or long call. We examine factors such as does the probability of one bird calling increase or decrease after another bird calls or is there a more subtle interaction going on? Working out how strongly each bird influences another helps us to build a picture of the communication network that is going on in that group of birds.”

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