If you click on any images in the blog, it will be opened in a separate window, will be larger and it will be easier to see detail.

Blog posts after 1 Feb 2018 about Steppe eagles tracked from Oman can be found at the Steppe eagle blog

Sunday, October 13, 2019

171326 a change in home range.

by B.-U. Meyburg & M. McGrady

Most of the Egyptian vultures we captured and fitted with satellite transmitters in January 2018 were apparently settled territory holders.  From the very beginning tracking has showed them to move between their territories and the dumpsites and landfills that they regularly visit for food.  However, a few were not settled, and presumably were "floaters", birds that had no fixed territories (and no mates).  171326 appeared to be such a bird.

Below are maps of the last 20,000 locations and last 5,000 locations of  Egyptian vulture 171326.  As can be seen, this bird was spending almost all of its time north of the eastern Hajar Mountains, but then shifted SW, and has more recently settled into an area south of Sayq and has made forays out toward and beyond Birkat al Mous and even visiting Jebel Shams.

The last 20,000 locations of  an adult Egyptian vulture (171326), up to 13 October 2019. Click on map to open in a new window for easier viewing.
The last 5,000 locations of  an adult Egyptian vulture (171326), up to 13 October 2019. Click on map to open in a new window for easier viewing.

Thursday, September 5, 2019

Vulture Awareness

by M. McGrady and B. -U. Meyburg

International Vulture Awareness Day is on Saturday 7 September.  As a warm up to that, below is a animation of the movements of some of the Egyptian vultures we are tracking in Oman.  In case you have not been following the blog, we tagged 13 Egyptian vultures in 2018, thinking that the large increase of vultures at dump sites in Oman was the result of migrants arriving from farther north.  To our surprise all the tagged vultures except one stayed in Oman (one hopped over to southern Iran), and most of them seemed to be territory holding birds.  This led us to believe that the resident population of Egyptian vultures in Oman was in fact much larger than suspected  (click here).  In spring 2019 a field team confirmed this by finding over 60 vulture breeding territories in a restricted area south of Muscat, indicating that Oman truely is a stronghold for globally Endangered Egyptian vultures.

Below is a short animation of a few weeks of movements by some of our tagged birds.  What it shows is that birds are dwelling on their territories most of the time, making almost daily trips to the landfill (pink triangle near the middle), and every once in a while they wander more widely.  The animation was assembled by John Burnside at the University of East Anglia (Thanks, John).  John is working on McQueen's (houbara) bustard.  You can learn more about his work here https://www.sustainablehoubaramanagement.org/ and on Twitter  @SustainHoubara  https://twitter.com/SustainHoubara?s=17












Thursday, August 29, 2019

Ranging by 171325 during August 2019

by M. McGrady and B.-U. Meyburg

It's been about 1.5 months since we last posted anything about the vultures we are tracking.  During that time most of the vultures have been spending time on their territories, making regular visits to the Al Multaquaa dump, and only occassionally wandering more widely.  Although we do not have information on productivity from the vultures, judging from the tracking data, it seems that some birds actually raised some offspring.  It certainly would be nice in future years to confirm this, and start to understand how productive the breeding population of Egyptian vultures in Oman really is. 

The map below is typical of what the territorial birds have been doing.  The map is of the last 500 locations for vulture number 171325.  It has a territory inland from Yiti and As Sifah.  It makes regular trips to the landfill at Al Multaquaa, but also made a long trip to the rubbish dump outside of Ibra.  This behaviour is actually in line with what we found for non-breeding immature  (McGrady et al. 2017) birds in that this vulture makes regular visits to a source of abundant food, but also seems to keep tabs on more distant food sources.  This type of behaviour provides a hedge against the loss of the nearby source.  Of course the Egyptian vulture has no way of knowing that the Al Multaquaa landfill is likely to be a reliable source of abundant food for a long time.

McGrady M.J., Karelus, D.L., Rayaleh, H.A., Sarrouf Willson, M., Meyburg, B.-U., Oli, M.K., Bildstein, K. 2019.  Home range and movement of Egyptian Vultures in relation to rubbish dumps in Oman and the Horn of Africa.  Bird Study 65: 544556.

GOOD NEWS FROM PORTUGAL:  A national action plan for necrophagus birds has been published https://www.4vultures.org/2019/08/22/portuguese-action-plan-for-the-conservation-of-necrophagous-birds-finally-published-in-di%C3%A1rio-da-rep%C3%BAblica/?fbclid=IwAR1TiPg3U2AR5Y-v434Cmz3X8ifbavXqICCEcHiZzDWmLyjsoYmnD5JyW38

Last 500 locations from an adult Egyptian vulture (171325) up to 28 August 2019.

Sunday, July 7, 2019

Sunday morning movements

by B.-U Meyburg and M. McGrady

Below is a map which shows the last 1000 locations of Egyptian vulture 16095.  We are collecting data at a high rate (maximum 1 location/sec depending on solar power constraints).  The map shows that this bird spent earlier parts of the morning at the Al Multaqa landfill. It then started soaring over the landfill and gained altitude, then flew in a straight line about 2 km to the south, circled once more to gain a bit more altitude, then perched.

Analyses of such data can allow us to understand the flight behaviour of vultures in relation to weather information, topography and location of food resources.  Such understanding can help conserve vultures by enabling us, for example, to better understand the risk of collision at wind farm sites, and adjust turbine placement accordingly.

Movements of an adult Egyptian vulture during the morning of 7 July 2019

Tuesday, May 28, 2019

Scavenging birds are important waste managers in Arabia

 Click on the link to see a recent opinion paper by M. McGrady, T. Al Amri, and A. Spalton

https://www.natureasia.com/en/nmiddleeast/article/10.1038/nmiddleeast.2019.80​

Human waste managers at Al Multaqa Engineered Landfill outside Muscat with their vulture colleague.


Sunday, April 7, 2019

Its the breeding season for Egyptian vultures in Oman

by M. McGrady and B. -U. Meyburg

In January 2018, when we caught the vultures we are currently tracking, we assumed that most of them were from migratory populations and that they would leave Oman during the breeding season.  However, to our surprise NONE of the birds we tagged were migratory, and that suggested instead that the breeding population in Oman is much larger than had been estimated (100 pairs, Jennings 2010), especially given the large increase we had recorded on Masirah (Angelov et al 2013)

In February-March of this year, a multi-national team (Ivaylo Angelov-Bulgaria; Clémentine Bougain-France; Michael Schulze-Germany) spent three weeks in Oman trying to determine whether the vultures we were following were indeed breeding, and to find other breeding pairs.  To do this they used tracking data to identify the territories of tagged birds, which they visited to confirm occupancy.  Then, using that as a framework, searched for signs (faeces at perch and nest sites, and attendant birds) of territorial pairs in the vicinity.  This was not always easy work because much of the area is in difficult terrain with few roads, and the nests are sometimes not in places where they can be easily observed.

Searching for signs of territorial Egyptian vultures. Photo by the EV Team.
Nonetheless, the team were able to confirm apparent breeding by most of the tracked birds, with some birds apparently starting to incubate eggs by the first week in March.  They were also able to find over 80 apparent breeding territories of Egyptian vulture within about 40 km of the main Muscat municipal landfill at Al Multaquaa, and they estimated there might be around 200 pairs in total in that area.

An Egyptian vulture inspecting a possible nest site, March 2019. Photo by the EV team
So, although it has been almost two months since our last positing, it is not the case that nothing has been happening... For their part Egyptian vultures in Oman have started breeding.  Once they lay eggs, they will need to incubate them for about 42 days, then the nestlings will remain in the nest for about 70-90 days (so an egg laid on 10 March would produce a fledgling in July).  We will continue to track vultures fitted with tags (below is an example of the movements of a vulture during March, showing that it has a territory located near Quriyat, but that it makes regular visits to the rubbish dump at Ibra).  We are also analysing more closely the results of the Feb-Mar breeding survey, and aim to publish that in the coming months.

Movements of a territorial Egyptian vulture during March 2019.
The team saw many more interesting things during their surveys; in the coming days we will try to post more information, so come back to the blog or follow us via email.

Tuesday, February 12, 2019

News from Ethiopia


This from Stoyan Nikolov from Bulgarian Society for Protection of Birds:

In January 2019, a joint expedition of BSPB, RSPB, BirdLife Africa, EWNHS, SCF, NCF and APLORI, under the support of the local experts and authorities, went to Ethiopia with three main objectives:

(1) monitor the numbers of Egyptian vultures in the wintering congregation site in Afar and small part of Oromia region;

(2) collect evidence on the major threats (poisoning, electrocution/collision, and direct persecution) which to inform adequate conservation measures;

(3) deploy transmitters on Egyptian vultures in their wintering grounds.

Briefly:

(1) 1,644 Egyptian vultures were counted to roost in the studied area (1,019 adults/subadults, 644 immatures/juveniles, and 44 birds with unidentified age). This is the highest number recorded so far, compared to previous surveys (2009, 2010 and 2013);

(2) Electrocution and collision with power lines was evidenced to cause significant mortality. We inspected over 180 km of dangerous power lines (medium and low voltage) for electrocution and
collision victims. We found a total of 42 carcasses of birds, including 6 Egyptian Vultures and 9 other vultures. Of these carcasses, 22 were victims of electrocution and 15 were victims of collisions with the power line. Most of the victims were concentrated along killer power lines in the areas of Metehara (grassland with high abundance and easily accessible food for scavengers) and Logia (along two rubbish dumps with high abundance of scavengers). Further steps for mitigation of this problem will be done in synergy with MSB II project.

Based on the information collected from the authorities and local stakeholders, non-intentional or intentional poisoning (including with veterinary medical products toxic for vultures) does not seem to be a systematic serious threat for the Egyptian and other vultures in the studied area, neither is direct persecution. However, further investigation will be needed especially re poisoning as an adult individual was found at a rubbish dump and the autopsy of the bird suggests intoxication with heavy metals (final analyses yet to be completed).

(3) Seven Egyptian vultures (2 adults + 5 immatures) were trapped and tagged with GPS-GSM transmitters in the rubbish dumps in Metehara and Logya. You can follow their daily movements via our website. http://www.lifeneophron.eu/#transmitters

Thursday, February 7, 2019

Detailed flight to foraging at a rubbish dump.

by Ivaylo Angelov, Bernd Meyburg and Mike McGrady

The transmitters we have used on some of the Egyptian vultures that we have been tracking since January 2018 can, when light conditions allow, collect location data every second.  This means that very detailed tracks of the birds' movements can be mapped.  When analysed closely along with information on weather, terrain and habitat, we can start to understand more about vulture flight.  This can be important, for example, in understanding the likely risk of vultures colliding with wind turbines, and making decisions about turbine placement and size.

Ivaylo has been taking an initial look at those data.  Below is a short story about a 53 km flight by an Egyptian vulture (171328) between its territory near Quriyat and the rubbish dump at Ibra.


On 9.03.2018 at 6:59:35, 171328 took off on a long foraging flight to the rubbish dump near Ibra – 47 km straight-line distance to the southwest. This bird regularly forages at the dump; this was one of 90 such flights that were made in 2018, and one of the 9 this bird made in March. During 2018 this bird also made 49 flights to the main landfill of Muscat at Al Multaquaa, 47 km to the west.

The 53 km track of an Egyptian vulture from its territory near Quriyat to the rubbish dump at Ibra. Yellow pins indicate thermal soaring (Viewed from the NE).
Thanks to the south-facing slopes, the initial third of the route (25 min) was transited in almost level gliding flight, with only two quite brief instances of thermal soaring.

At 7:25 the bird flew over the village of Tool (270 m asl), and started ascending in order to cross the mountain ridge south of it (1070 m asl).  To transverse the next 5.5 km and the rising terrain (from 426 to 1662 m asl), the vulture used, during a period of 19:39 minutes, seven consecutive uplifting thermals.  During the time spent in gliding flight between the thermals, the vulture lost only 58 m in elevation.
View of flight from the west, showing the use of seven thermals to gain altitude and cross the rising mountains (viewed from the east).
Upon reaching the peak of the central ridge, the vulture flew into and utilised the highest thermal of the flight, which it used for 4:12 min to gain an additional 589 m in elevation, reaching 1662 m asl. While using the thermal the vulture also encountered a strong headwind, which pushed it back in the direction of Quriyat. 
Use of a thermal at the ridge of the Eastern Hajar Mountains (viewed from the east).
After covering another 11 km, the vulture entered two, spatially close, consecutive thermals, in which it spent 5:08 min and gained 507 m of altitude (Map below).


The last (15) thermal soaring occurred 6 km north of the Ibra dump site, over flat terrain above a wadi.  The vulture spent 2:08 min in that thermal, and gained 314 m of elevation.  From the top of the thermal it descended to the dump site, arriving at 08:30.
The final (15th) thermal flight by the Egyptian vulture before descending to the rubbish dump at Ibra (viewed from the east).





Thursday, January 24, 2019

A new paper on foraging by Egyptian vultures in Oman

A juvenile Egyptian vulture fitted with a solar-powered satellite transmitter in 2017.
Analysis of data from tracked juvenile Egyptian vultures in Djibouti and Oman suggests that, even when food is plentiful and concentrated in a single place, they will forage over large areas, thereby keeping abreast of the current availability of food.  This behaviour would of course be advantageous because information on food availability is a hedge against the ephemeral food on which vultures typically rely (Download the paper by clicking on the link below). Adults may be doing the same thing, albeit affected by breeding/territoriality.  But that is another paper, which may arise from data we are collecting in Oman. 

For information on the bird tracked in Djibouti, See  https://egyptianvulturedjibouti.blogspot.com/

Click here to download document