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Eurasian Griffon Vulture - Gyps fulvus
#1
Eurasian Griffon Vulture - Gyps fulvus

[Image: photo.jpg]

Scientific classification 
Kingdom: Animalia 
Phylum: Chordata 
Class: Aves 
Order: Falconiformes (or Accipitriformes, q.v.) 
Family: Accipitridae 
Genus: Gyps 
Species: Gyps fulvus

The Griffin Vulture or John Griffin Vulture (Gyps fulvus) is a large Old World vulture in the bird of prey family Accipitridae.

[Image: Gyps_fulvus_dis.png]
Dark green: areas of year-round habitation

Physical Description
The Griffin Vulture is 93–110 cm (37–43 in) long with a 230–269 cm (91–106 in) wingspan, and it weighs between 6 and 13 kg (13.2 and 29 lb). Hatched naked, it is a typical Old World vulture in appearance, with a very white bald head, very broad wings and short tail feathers. It has a white neck ruff and yellow bill. The buff body and wing coverts contrast with the dark flight feathers.

[Image: photo.jpg]

Diet
Like other vultures it is a scavenger, feeding mostly from carcasses of dead animals which it finds by soaring over open areas, often moving in flocks. It grunts and hisses at roosts or when feeding on carrion.
Although the Griffon Vulture does not normally attack larger living prey, there are reports of Spanish Griffon Vultures killing weak, young or unhealthy living animals as they do not find enough carrion to eat.

[Image: photo.jpg]
Breeding
It breeds on crags in mountains in southern Europe, north Africa, and Asia, laying one egg. Griffon Vultures may form loose colonies. The population is mostly resident.

Status in Europe
  • In Italy, the species survived only in Sardinia, but was re-introduced in a few other areas of the peninsula. As a result, several specimens been spotted again in August 2006 on the Gran Sasso massif (central Italy). 

  • In Croatia, a colony of Griffon Vultures can be found near the town of Beli on the island of Cres. There they breed at lower elevations, with some nests just 10 m above sea level. Therefore, contact with people is common. 

  • In Cyprus, there is a colony at Episkopi, in the south of the island. 

  • Colonies of Griffon Vultures can be found in northern Israel, especially in the Golan Heights where a large colony breeds at Gamla, and in the Carmel Mountains and the Negev desert, where reintroduction projects are being carried out at breeding centers in the Carmel and Negev. 

  • In Greece, there are nearly 1000 birds. On Crete they can be found in most mountainous areas, sometimes in groups of up to 20. 

  • Griffon Vultures have been re-introduced successfully into the Massif Central in France; about 500 are now found there. 
    In Belgium and the Netherlands, around 100 birds were present in the summer of 2007. These were vagrants from the Pyrenees population.

  • In Germany, the species died out in the mid 18th century. Some 200 vagrant birds, probably from the Pyrenees, were sighted in 2006, and several dozen of the vagrants sighted in Belgium the following year crossed into Germany in search for food. There are plans to reintroduce the species in the Alps. In September 2008, pieces of a griffon vulture bone, about 35,000 years old, were excavated from Hohle Fels cave in southern Germany, which are believed to form a flute. 

  • In Serbia, there are around 60–65 pairs of Griffon Vultures in western parts of the country, around Zlatar mountain,also 35 birds in canyon of river Trešnjica and they are under legal protection from hunting. 

  • In Switzerland, there is a population of several dozen birds. 

  • In Austria, there is a remnant population around Salzburg Zoo, and vagrants from the Balkans are often seen. 

  • In Spain, there are tens of thousands of birds, from a low of a few thousand around 1980. 

  • The Pyrenees population has apparently been affected by an EC ruling that due to danger of BSE transmission, no carcasses must be left on the fields for the time being. This has critically lowered food availability, and consequently, carrying capacity.

[Image: photo.jpg] 
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#2
Study shows how vultures evesdrop to gather vital flight information

Social network helps birds pick best way of using thermal updrafts

Date:  November 7, 2018
Source:  Swansea University

[Image: 181107130309_1_900x600.jpg]
Footage of a vulture in flight caputred during the research.
Credit: Hannah Williams

A new study has revealed how vultures use their very own social networks to work out the best way to take advantage of thermal updrafts to help them fly vast distances.
The research, carried out by a team from Swansea University led by PhD student Hannah Williams, examined how the vultures seemed to make risky but efficient choices in flight when they observed the flight of other vultures in the network.
Their paper Social eavesdropping allows for a more risky gliding strategy by thermal soaring birds has just been published in the Journal of the Royal Society Interface and Hannah hopes it will help provide a better understanding about the strategies birds use to navigate the aerial landscape.
She said: "Thermal updrafts are chaotic in their occurrence, so it makes sense for these heavy birds to 'eavesdrop' on the movements of other birds to find thermals, just as human pilots do when gliding.
"We worked with Dr Olivier Duriez, of the University of Montpellier, to track the movements of five vultures at a bird of prey centre in France, using special tag technology contained in backpacks worn by the birds.
"We hypothesised that birds would fly towards areas where other birds had been circling and that they would do so at fast speeds. It is a risky flight strategy to glide at fast speeds, but it appears they may take this risk when using information from the network."
Working with her co-authors from the Swansea Laboratory for Animal Movement and SHOALgroup, both based in the University's Biosciences Department, Hannah explained that the research data was collected in just three days but it had taken more than six months to design the necessary tracking experiment and the tag technology.
She said: "This is part of a multi-year collaboration and the design of the tags, which notably collect high-frequency airspeed data, has been a long and challenging process.
"From here we hope to delve further into how birds may acquire information from other birds in the sky, to make better movement choices. "
Co-author Dr Andrew King, of the Department of Biosciences, said: "We are used to hearing about how flocking species like pigeons and starlings use social information. This data, gathered simultaneously from a number of soaring vultures, provides a great example how relying on others for information can be beneficial at a very different spatio-temporal scale."
Hannah, from Lancashire, completed her doctorate last year after studying with the Swansea Laboratory for Animal Movement and SHOAL. She said: "This publication was the project that brought all the aspects of my PhD together -- animal attached logging devices, flight dynamics and social behaviour.
"Thanks to a great set-up in France using captive birds that could fly freely each day and a team of hardware engineers and movement specialists at Swansea University, we were able to collect the high-frequency flight data needed to investigate this eavesdropping behaviour."
She now plans to continue her research into animal movement at the University, working with Dr Emily Shepard, from the College of Science, studying flight patterns of condors.


Story Source:  Swansea University. "Study shows how vultures evesdrop to gather vital flight information: Social network helps birds pick best way of using thermal updrafts." ScienceDaily. www.sciencedaily.com/releases/2018/11/181107130309.htm (accessed November 8, 2018).



Journal Reference:
  1. Hannah J. Williams, Andrew J. King, Olivier Duriez, Luca Börger, Emily L. C. Shepard. Social eavesdropping allows for a more risky gliding strategy by thermal-soaring birds. Journal of The Royal Society Interface, 2018; 15 (148): 20180578 DOI: 10.1098/rsif.2018.0578
Abstract
Vultures are thought to form networks in the sky, with individuals monitoring the movements of others to gain up-to-date information on resource availability. While it is recognized that social information facilitates the search for carrion, how this facilitates the search for updrafts, another critical resource, remains unknown. In theory, birds could use information on updraft availability to modulate their flight speed, increasing their airspeed when informed on updraft location. In addition, the stylized circling behaviour associated with thermal soaring is likely to provide social cues on updraft availability for any bird operating in the surrounding area. We equipped five Gypsvultures with GPS and airspeed loggers to quantify the movements of birds flying in the same airspace. Birds that were socially informed on updraft availability immediately adopted higher airspeeds on entering the inter-thermal glide; a strategy that would be risky if birds were relying on personal information alone. This was embedded within a broader pattern of a reduction in airspeed (approx. 3 m s−1) through the glide, likely reflecting the need for low speed to sense and turn into the next thermal. Overall, this demonstrates (i) the complexity of factors affecting speed selection over fine temporal scales and (ii) that Gyps vultures respond to social information on the occurrence of energy in the aerial environment, which may reduce uncertainty in their movement decisions.

http://rsif.royalsocietypublishing.org/c...8/20180578
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