Assamo: 1-17 December 2013.

On 21 November Assamo moved back from the Ethiopian town of Adigala to northern Djibouti.  See last post.  He has moved around Obock and in the vicinity of Tadjoura (interestingly we have not yet recorded him revisiting the abattoir were he was first captured).  Surprisingly, on 16 December Assamo returned to Adigala.

Also, on 30 November there were two interesting locations over the sea about 5 km from land. Vultures are soaring birds and in general avoid flying over large areas of open water because these places normally do not have strong thermal updrafts.  Also, this is not migration time.

Assamo's movements during late November - early December.  The southerly cluster of locations is around Adigala.

Assamo back in Djibouti

Early on 20 November Assamo was still hanging around Adigala, where he has been since the beginning of July (almost 5 months...look at earlier posts).  However, he started to move on that day and in the evening roosted about 20 km NW of the Djiboutian town of Ali Sabieh.  On 21 November Assamo left his roost early and by 0930 was already at a location about 15 km NE of Tadjoura (where he was caught back in March).  He has stayed in that area since, and on 29 November was located about 30 km NW of Obock. Interestingly, since moving into Djibouti, he seems now to be moving around amongst small settlements, rather than focusing on a larger population center like Adigala.

Assamo moves back to Djibouti, late November 2013.

Just as Assamo has left Ethiopia, another has arrived from Bulgaria.  Have a look at the the movements of Svetlina.

Finally, some more bad news about poisoning of vultures in southern Africa:  https://www.facebook.com/andre.botha3/posts/10151763127104080:0 

A little variety

Just when I was tiring of looking at week after week of Assamo staying in and around Adigala, Ethiopia, he varied his behaviour just a bit.  During 5-19 November, most of the activity was in the vicinity of Adigala, but on 10-11 November Assamo headed northeast as far as the Djibouti border near Dewele, a move of about 100 km, one way.  At one point Assamo was < 500 m from being back in Djibouti.

127589's movements during 5-19 November 2013.  The more southerly cluster of locations is the town of Adigala.  The most northerly is near Dewele.

Also, electrical infrastructure including pylons can pose threats to vultures, but they are also ideal perching locations.  See below.

Locations at a power pylon. Power infrastructure can pose threats to vultures, but in this case Assamo used the pylon as a perching place.

If you are interested in sooty falcon migration that we are tracking then have a look at our other blog  http://sootyfalcon.blogspot.co.at/

Also, don't forget to visit the Vulture Chronicles, where news about hooded vultures is available http://hawkmountain.wordpress.com/

Still Adigala

Assamo has remained in Adigala and the surrounding area during 14-27 October.  It seems to roost mostly on power lines to the south and commute into the town every day,  Maybe these are not the most exciting movements, but it is still interesting because we know so little about the movement of Egyptian vultures in this (or any other) area.

Movements by Assamo during 14-27 October 2013.

Assamo is settled

During the past 10 days Assamo has been behaving much as it has over the past few months.  He has stayed in and around Adigala, Ethiopia.  When he is not in the town it seems that he spends time roosting along the surrounding roads, presumably on electricity pylons.

In another vulture development, Hawk Mountain had fitted four hooded vultures with transmitters in the Gambia.  Have a look at what they are doing:  http://hawkmountain.wordpress.com/

Assamo's locations during 4-10 October, 2013.

Assamo still in Adigala

Assamo spent early September mostly around Adigala (See map below).  His movements during these two weeks are very similar to movements in the past three months.  On 8-10 October he did make an excursion about 9 km to the north.  There he spent time near a new road that runs through the hills just south of a mining operation.  I tried to find out about mining in the area using the internet, but did not have any luck.  The Adigala block is an area being leased for oil exploration, but I think this is at a quite early stage and I don't know if any exploration wells have been drilled yet.  Does anyone know about mining activity north of Adigala?

Assamo's movements 1-16 September 2013.

In other vulture news...

Bulgarian Egyptian vultures are on the move: http://lifeneophron.eu/en/news-view/196.html
In Andalucia Egyptian vultures are breeding again   www.4vultures.org/news  They had been extirpated three years ago, but an anti poisoning campaign seems to be reaping benefits.

 

Even more Adigala...3 September 2013

 REMINDER: SEPTEMBER 7 IS INTERNATIONAL VULTURE AWARENESS DAY

Assamo has spent the last two weeks where it has been since late June.  So, it has been scavenging in and around Adigala for almost 3 months now.  It did make a brief excursion during 30-31 August to locations SSW of the town, near the village of Ghedid Cali. Ghedid Cali is on the road toward Dire Dawa.  Does anyone know anything about Ghedid Cali?  It must be a very small place.  The satellite image used by Google Earth is not very good.

Assamo's movements during 13 August - 3 September 2013.

As with previous blogs the pattern of locations suggest that Assamo is perching often on the power transmission pylons.  The map below also shows that his movements are mostly on the outskirts of town.  I suppose that this is because people will dispose of their waste outside the town and its likely that the slaughter house is also away from town centre. 

Assamo seems to frequent the outskirts of Adigala.

Finally... some bad news, and what is being done about it:

From National Geographic

From Birdlife

Three pieces from Stoycho Stoychev, Bulgarian Society for the Protection of Birds

http://bspb.org/show/2759-33

http://bspb.org/show/2756-33

http://lifeneophron.eu/en/news-view/187.html

Still Adigala

In early August 2013 Assamo stayed very close to Adigala.  Although I have never been there, given the pattern of locations I'd guess the abattoir is on the western edge of town (Look back at the previous post).  Can anyone who has been to Adigala tell me where the abattoir is located?  Or can someone tell me what might be so attractive to this vulture out on what I think is called "Mosque Road"?

GPS locations of an Egyptian vulture around the town of Adigala, Ethiopia, August 2013.

Now for a little lesson about the data we get from the transmitter fitted to Assamo...

Two types of locational data are received: GPS and Doppler.  GPS locations are calculated by part of the transmitter on the bird's back.  It "looks" for satellites that are at known positions, then calculates from its position relative to those satellites its own location.  Doppler locations are determined by a series of moving satellites "listening" for a pulse from the transmitter on the bird's back.  Because the locations, paths and velocities of the satellites are known,  the Doppler shift in the pulse's frequency can be used to calculate the likely location of the bird.  The map below shows Doppler data (red) and GPS data (green)

Doppler (red) and GPS (green) locational data for Assamo in early August 2013.

You will notice a few features:  Doppler locations tend to be dispersed over a wider area.  This is because the Doppler system is less accurate than the GPS.  You may then ask: "Why collect the Doppler data?"  Well the main reason in this case is that the pulse used to calculate the Doppler location is also the means by which the GPS data that are held in the transmitter are transmitted to the satellite and on to us.  Using the Doppler system to calculate location also has the advantage of using less power.  While this is not so important when tracking an Egyptian vulture in Ethiopia because the bird is rather large and the transmitter is solar powered, it can make a difference when one is trying to track a smaller bird or using battery power only.  Thus, the really small satellite transmitters used to track things like cuckoos and Amur falcons, etc do not use the GPS system, but rely totally on the Doppler system to calculate bird locations.

Close up of locations around Adigala in early August 2013

The use of the transmitter pulse to transmit GPS data also results in many more GPS locations per Doppler location.  So, in the case of Assamo, a number of GPS locations will be calculated and stored on board the transmitter, then these will be transmitted via satellite to us, and the pulses used to transmit those data will be used to calculate a "Doppler fix".

Adigala

As the previous blog posts have stated, Assamo has spent most of the last month and a half around the Ethiopian town of Adigala.  Here is what Houssein Rayaleh of Djibouti Nature (a conservation NGO) has to say about Adigala:

Adigala is an underveloped large-sized village in eastern Ethiopia close to the border of Djibouti and Somalia; it has no industry. In common with many other important human settlements in the Somali region of Ethiopia, Adigala has no formal waste management system 

Ethnically Adigala’s population and that of the surrounding area is Somali, and are mainly pastoralists who use an open range rearing livestock system.  The lack of a waste management system coupled with the pastoral way of life of the inhabitants means that Adigala  produces large amounts of waste, including waste from its abattoir.

As with many areas in the Somali region of Ethiopia, the area around Adigala is underexplored, though recently petroleum reserves have been proven and prospecting for other mining resources occurs.

The recently constructed electricity transmission line that connects Ethiopia with Djibouti crosses Adigala. Pylons from the source of power to destinations in Djibouti are often used as perch sites for raptors, including Egyptian vultures.  Near villages like Adigala the use of pylons as perches by Egyptian vultures is particularly common.  The pylon design is similar to that found in Djibouti.  Large transmission pylons probably pose little threat of electrocution, but smaller power lines in and around settlements are likely to be more dangerous.

Satellite image of Adigala. Click on the image to enlarge or use the search function in Google Earth to explore more closely.

Assamo in late July 2013

In late July 2013, Assamo really did not move very far.  He spent the whole of the month within < 20 square km around the town of Adigala.  Does anyone know anything about this town? Does anyone visit it?  I suppose Assamo is perching on some power pylons to the north of town.  At some locations we have more than 15 individual fixes for him.  This suggests to me a favorite perch on a specific pylon.

Assamo's movements around the town of Adigala, Ethiopia in late July 2013.

Below is a zoomed out map, which shows just how small the area is that Assamo has been using, and its position relative to regional geography.

Assamo's locations in late July 2013 as seen at a regional scale.

 The Egyptian vulture is a globally endangered species, and huge declines in the population have been seen over the past 50 years or so.  Despite this, and the instances of human related deaths we have talked about in other blog posts, there are some stories of success that give us hope.  Here is a video about the release of a captive bred Egyptian vulture in Italy in 2005, and another release is scheduled for this month.  Good news is always welcome!

Sadly, in South Africa recently almost 50 vultures were found dead.  Click here to find out more.  The cause of death is suspected to be poisoning when they fed on poison-laced sheep carcasses, presumably laid to target jackals.  This incident highlights a number of things: vultures (and other animals) are being poisoned in large numbers, because of their foraging and feeding ecology large numbers of vultures can die at single poisoning events, and the number of adult vultures killed suggest a large impact on the population and its potential productivity because these species are normally long-lived and mature only after a number of years.

Early July 2013. Assamo stays in Ethiopia.

Assamo spent all of early July 2013 (2-12) around the town of Adigala in Ethiopia.  Although I have never been there and have noinsider information, I guess that the abattoir or rubbish dump is to the east of the town because this is where Assamo has spent most of his time.  During 10-12 July Assamo wandered a bit to the east and south, but stayed within 20 km of Adigala.

Assamo's movements around Adigala, Ethiopia, 2-12 July, 2013.

Assamo is in Ethiopia

During the last two weeks of June Assamo has been in eastern Ethiopia, near the borders with Djibouti and Somalia.  He has spent a lot of his time around the town of Adigala.   I tried to find out more about the region, but was unsuccessful.  There seems to be at least some potential for oil development, but that seems to be prospective at the moment.

Assamo's locations during 17 - 30 June 2013.

The pattern of locations off to the south of Adigala suggest (to me at least) that there might be a power line that parallels the road, and that Assamo may be perching on the pylons.  I hope they are safe!   His last location is the one that is farthest south.  We'll have to wait to see if he keeps moving.

Assamo moved within a fairly limited area around Adigala, Ethiopia during 17-30 June 2013.

Assamo and pylons

Assamo spent the first half of June in southern Djibouti, mostly around the town of 'Ali Sabieh (see map below).  If you look back at past posts you will see that he has been here for about a month now, and had visited here earlier in the year.  Although he is in the same general area, it seems Assamo is no longer the commuter he was during the end of May.

Assamo's locations during 1-14 June 2013

During this period Assamo spent much of his time on power pylons along the N1 road north of 'Ali Sabieh.  Have a look at the two images below and you can see the pylons on which Assamo roosted.  This highlights a problem that vultures and other birds face: Electrocution.  Electrocution can be a significant cause of mortality, especially for large soaring birds.  Some pylons designs are more dangerous than others and most of the ones we saw in Djibouti seem to be relatively benign.  Indeed, the pylons in these images appear to be large enough so that electrocution is unlikely.

Here is a link to a report from Bulgaria about an Egyptian vulture electrocuted there, and here is one thing the Bulgarian Society for Protection of Birds is doing about it.  Still, if you want to read more about this problem, try to dig out this reference:

Angelov, I., Hashim, I., and Oppel, S. 2012.  Persistent electrocution mortality of Egyptian vultures Neophron percnopterus over 28 years in East Africa. Bird Conservation International 1-6.

Some of Assamo's locations on electricity pylons.

Some more of Assam's locations on an electricity pylon in southern Djibouti.

Assamo the commuter: 19 - 28 May 2013

This monitoring period had two distinct phases.  At the beginning of the period, on 19-20 May, Assamo was located mostly around Obok, in northern Djibouti (See map below).  On the 21st he moved NW to a place near Egahlou (he visited here on 16 May. See previous post).  By the 0830 on the 22nd he was already heading south and west, and between 0830 and 1130 he traveled about 90 km to what appears to be the rubbish dump at the town of Ail Sabieh, then by 1430 on that day he was located just inside the Ethiopian border about 10 km to the south.  This is the beginning of the second phase of this monitoring period.

Assamo's movements started in northern Djibout, near Obok (19 May 2013).  He moved south on 22 May 2013

The second phase of this monitoring period was characterized mostly by Assamo being a commuter to and from Ali Sabieh.  He is what happened:

22 May 1130 in Ali Sabieh, 1430 in Ethiopia
23 May 0530 in Ali Sabieh, 0830 in Ethiopia
24 May 0530 in Ali Sabieh, 1130 in Ethiopia
25 May 0830 in Ali Sabieh, 1430 in Ethiopia
26 May 0830 in Ali Sabieh, 1430 in Ethiopia
27 May 0830 in Ali Sabieh, 0830 in Ethiopia, 1130 back just east of Ali Sabieh, 1430 farther north
28 May 0830 in Ali Sabieh, 1130 back north of town. 

The map below shows the locations in Ethiopia and in Ali Sabieh

Assamo's locations in Ali Sabieh, and along the Djibouti-Ethiopian road, just over the border in Ethiopia.

Assamo: 4-17 May 2013

Assamo's movements during 4-17 May 2013

Though Assamo hasn't moved very far during this time period, those movements are still interesting... At least to me they are. Assamo spent most of this time near permanent/semi-permanent settlements (when I zoom in on Google Earth there are cement buildings and fenced compounds).  These settlements are located on two arms of a large wadi system, so most of Assamo's locations fall within a circle of about 30 km.  He did make some forays out to the NE (16 May) near Egahlou, to the West (5 May) near Airolaf and even to Tadjoura (6 May).  We have not recorded him re-visiting the site where he was caught.  That could be because locations are determined at intervals throughout the day, and so he could have visited and we missed it.  Of course, it could also be that he just hasn't gone back to the Tadjoura abattoir.

Assamo visits Eritrea

Assamo made an excursion to Eritrea on 2 May 2013.

During the period shown on the map (28 April - 2 May) Assamo behaved much like he has in the past, mostly moving between settlements to the north of Tadjoura town in northern Djibouti.  However, on 2 May Assamo was located briefly in Eritrea in the Danakil province in the south.  This movement seems very much like a short excursion because 3 hours before and 3 hours after being located in Eritrea, Assamo was moving around north of Tadjoura, 75 -90 km to the southwest.  So, since trapping, Assamo has spent most of his time in Djibouti, but has ranged widely within that country.  He has also made excursions to Ethiopia and now Eritrea, albeit short excursions in both instances.

Assamo: 19 - 28 April 2013

Nothing much to report.  Assamo keeps moving around north of the town of Tadjoura, where we caught her/him.  He seems to keep his distance. Locations are 15 - 60 km distant from the town.  Tadjoura has a daily abbatoir, which attracts vultures.  When we were there we saw 20 - 60 vultures of various ages.  It seems curious that Assamo has not returned to the site, despite it having a predictable and plentiful source of food.  It seems almost certain that Assamo is not a breeding bird.  At least not in this year.

In past blog posts I have mentioned how most of these locations are near small settlements (use the kml, available in the last post to see for yourself).  Just remember that the Google Earth satellite imagery is from 2006, so just because we don't see a settlement on Google Earth, does not mean there is not one today.

Assamo's movements during 19 -28 April 2013 (double click on map to enlarge in a new window).

Assamo kml

For those of you with Google Earth I have posted a kml here of Assamo's movements during 5-14 April 2013. With this you can better see what Assamo has been doing.  When you open the kml it should give you a view similar to the one below. You can zoom into locations and see that some of them are very close to human habitation or roads.  Some of the locations near roads may also be when Assamo is perching on a power pole, which could be an electrocution hazard for him/her.  So far so good, but Assamo lives in a hazardous environment... Although Djibouti does not seem to be as hazardous as other places.  More on that in a later post.  You will also see that many of the locations are at the same place, meaning Assamo spends a lot of time just standing around.

For those of you no used to Google Earth, if you put your cursor on a location and left click, then properties will be shown of that location, including date, time and other information.

Map of locations in downloadable kml

Assamo on the move again: 5-18 April 2013

Assamo's move back to northern Djibouti

Well, I guess I will have to make more frequent postings because if I leave it too long then it is a bit time consuming to create maps of Assamo's movements... He's just moving so much.  So, excuse me for not tidying up the map above.  Here is what Assamo has been up to:

5-13 April Assamo was mostly in any around the town of Ali Sabieh in southern Djibouti, just north of the Ethiopian border.

14 April he was in the town of Ali Adde in the morning, then near the road going into Ethiopia, close to the border.

15 April he made a quick trip into Ethiopia on the road north of Denele, but then by later that day he was a couple of km south of Arta (in the map above, this is the small cluster of locations just south of the Gulf of Tadjoura.  He stayed there for the whole of the 16th and 17th, mostly near the road.

18 April at 0715 in the morning he was already north of the Gulf of Tajoura, and by 1015 he had covered the 60 km or so to a location about 32 km NE of Tadjoura town and NW of Obok.

I don't know about you, but I find this fascinating!
 

Poisoning of Egyptian vultures in Greece

Two Egyptian vultures were poisoned in northern Greece recently (first week of April).  Pictures and a text in Greek can be found on the website of the Hellenic Ornithological Society and on the Return of the Neophron website.  In short... these birds were found because one of the vultures had been fitted with a satellite radio transmitter (like Assamo).  Its name was "Lazaros".  Lazaros was first poisoned in 2012 in Greece, but was rehabilitated, fitted with a transmitter and released.  It migrated south and spent this past winter in Chad (also a place where we know vultures are persecuted and killed).  This spring it was migrating back to its summering area in Greece when it was poisoned again. 

Illegal poisoning of scavenging is a problem in many parts of the world.  In this case it is likely that poisoned baits had been set for other predators, most likely mammals like foxes or dogs.  The Egyptian vultures then fed on the bait and died.  At the bait that first poisoned Lazaros was found a poisoned dog, and two weeks earlier in the same area two foxes were found poisoned.

Assamo's movements 27 March - 5 April 2013

Assamo makes a move south

Between 27 March and 3 April Assamo behaved very much as he/she has done since capture, moving from place to place, mostly to the north of Tadjoura.  On 1 April it moved to its closest location to Ras Siyyan (so far) and the Bab el Mandeb Straits.  On 3 April it broke from its previous behavior and headed to the south of Djibouti and Ethiopia, traveling over land and not flying over the Gulf of Tadjoura.  During one leg of this journey Assamo was moving an average of about 16 km/hr.  On the 3rd and 4th of April Assamo was in Ethiopia near Dewele, and on 4-5 moved back into Djibouti.  The last location on 5 April had Assamo in the town of Ali Sabieh..  I have posted something a bit different on the Vulture Chronicles blog, so have a look there, too.  It seems like Assamo is really not a migrant...this year at least.

From elsewhere

From France, Pascal Orabi from LPO says:

I also have the pleasure to announce you first observations of the Egyptian vultures of migration in France (for the first ones: the 07/03/2013 in the department of Ardèche, 21 and 25/03/2013 in the department of the Drôme and 10/03/2013 in the department of Bouches-du-Rhône).

From Bulgaria, Stoyan Nicolov of the Bulgarian Society for the Protection of Birds says:

We are happy to announce that the first Egyptian vultures for 2013 already
retuned in Bulgaria from their wintering grounds (on 17.3.2013 in Southern
part of the country and on 20.3.2013  - in the Northern part).

We wish them a successful breeding season!

From Yemen, Ibrahim Al Hasani of Birdlife says:

Hi, Many Egyptian vultures (tens) migrating northwards in the south western parts of Yemen, many aggregating on waste dump sites.

From Turkey, Can Bilgen from the Middle East Technical University says:

Merhaba,
    The first birds seem to have arrived at our study area about ten days ago.

Assamo's movements 18-27 March 2013

Assamo's movements during 18-27 March 2013.

As in the previous weeks, Assamo has moved widely, but within about 35 km of Tadjoura, where it was captured.  The pattern of visiting a variety of locations is continuing.  Some locations are visited quickly, at some Assamo spends some days, and some are revisited.  In other words, some days are characterized by movement, while others are characterized by more sedentary behavior.  In almost all cases, when we zoom in on locations, these are in the close vicinity of settlements or nomad camps.  By the end of this time period, Assamo was located back at the municipal dump site to the west of Tajoura, about 2 km from where he was captured

March 19, 2013: 3 hours at Ras Siyyan

Adult Egyptian vulture.  Photo by H. Rayaleh

On March 19, 2013, the sixth day of a birding tour that I organized for well known birders, and only ten days after the migration counts I made with Mike, Ali and Eleyeh at Ras Siyyan, on the Djibouti side of Bab el Mandeb strait, I traveled again to Ras Siyyan and made less than three hours (3) of  observations at one of the locations (VP2: 12°, 28.567'  43°, 19.075') on the volcanic cone used to monitor migration during our earlier effort.

Compared to our earlier trip, the weather conditions on March 19 were better.  Migration started after 0800, with the arrival of Egyptian Vultures flying very low over the lagoon mainly from the west. And from 0815 to 1030 we counted 459 EGVs, 900 Booted Eagles, 541 unidentified raptors (probably mostly EGVs and Booted Eagles; 1 Saker Falcon landed next to us followed by a Levant Sparrowhawk.

During that time it seemed to us that the volcanic cone was totally shaded by the large number of raptors flying above it, before they crossed the strait to Yemen. 

16-17 March 2013

Locations of Assamo near a settlement during 16-17 March 2013

If one zooms in on the locations visited by Assamo (see previous map), one can see that they are always near settlements or in wadis (presumably where they might roost or where food might be located).  Above is an example, and shows four locations from afternoon on 16 March through the morning of the 17th.  Note the buildings about 200 m north of the locations. 

Tracking "Assamo" in Djibouti

Movement of adult Egyptian vulture 11-17 March 2013.  Dates are dd/mm.

The map above is a summary of the movements made by Assamo (NOTE: Dates are in the form of dd/mm).  In actuality there were many more locations in clusters around the points shown on the map.  We removed most of the locations to make the map clearer, and labelled locations with the data or range of dates when the bird was there.  So, we can see that Assamo has moved around a lot, moving between locations within one day, and sometimes spending more than one day at a location.  Some locations were revisited.  During this time it had moved up to about 40 km away from the location where it was trapped at Tadjoura.  We know that the abattoir at Tadjoura is a reliable source of regular food, so maybe this bird has been discouraged from returning there because of the capture.  However, our observations seem to suggest that not all vultures that are near to Tadjoura visit the abattoir every day, so what we might be seeing in this map is just normal behavior.

Fitting Egyptian vulture with GPS satellite transmitter

After trapping the adult Egyptian vulture, we moved away from the abattoir and into the shade.  There we fitted the vulture with a 40 gram GPS-PTT using a backpack harness.  The transmitter is solar powered and so has a theoretical life of some years.  It is programmed to acquire 8 GPS locations per day and send data every 2.5 days. 

Fitting GPS transmitter to Egyptian vulture.

 We also fitted this bird with a numbered metal ring from our Bulgarian colleagues.  We weighed and measured it and took a bunch of photos before we released it!  Before releasing it, we gave it the name "Assamo".

Releasing Egyptian vulture wearing GPS transmitter.

Trapping Egyptian vulture at Tajoura, Djibouti

Tajoura is the provincial capital of the Tajoura region of Djibouti, and has about 25,000 inhabitants. It is located on the northern coast of the Gulf of Tajoura.  Every morning domestic animals are slaughtered at the seaside abattoir in Tajoura, and this attracts numbers of Egyptian vultures.  When we visited this site on 1 March about 60 vultures of all ages were present; when we visited on 11 March there were about 25 and on 12 March there were about 18.

Tajoura abattoir at about 0900 in the morning.  Egyptian vultures (of all ages), Indian house crows and domestic cats can be seen

 On 11 March, at about 0830 we trapped a single adult Egyptian vulture and fitted it with a GPS satellite-received radio transmitter, and a Bulgarian Society for Protection of Birds numbered metal ring..

Houssein with an adult Egyptian vulture.  Note vulture's crop is full of food after a morning at the abattoir.

.

Embarkation

After about 1000 in the morning the migration ceased to embark from Ras Siyyan toward Yemen, and migrants were seen moving south down the Djiboutian coast, some gaining elevation from the thermals that were no doubt gaining strength as the day warmed up.  By 1100 almost no migration was visible from Ras Siyyan, and we spent afternoons searching for the main migration path.  We searched to the south and to the west, speculating that the migration was building in the mountains to the west and no longer passing over Ras Siyyan. 

Looking for the migration. On this day we did not see any migration over these coastal plateaus.

It wasn't until 10 March, as we were leaving the field, that we located the migration over two plateaus about 25 km south of Ras Siyyan on the coast.  Surprisingly though, migrants flying over these plateaus were still heading south, away from Yemen.  So, despite our best efforts, we never did determine where or how migrating raptors left Djibouti.  We think that they may leave across a rather broad front, departing as individuals or groups when they attain enough elevation to make the crossing.  For some they drift rather far south before heading over the sea.  This supposition is bolstered (maybe) by the fact that the arrival of birds on the Yemen side of the straits does not appear to occur at a single location (H. and G. Welch pers.comm.).

Ali and Eleyeh looking north from atop one of the plateaus located about 25 km south of Ras Siyyan.

The Team

The 2013 Djibouti Egyptian Vulture Team

Our team included: Ahmed Hamadou (seated), (standing left to right) Houssein Rayaleh, Mike McGrady, Eleyeh Abdillahi and Ali Darrar.  Ahmed is a local Afar and served as our guide.  Hossein is the director of Djibouti Nature, a wildlife conservation NGO.  Mike is an avian ecologist with International Avian Research. Eleyeh is a volunteer and has received training on monitoring Egyptian vultures at a workshop in Ethiopia, supported by European funding and the Bulgarian Society for the Protection of Birds. Ali is a vice principal at a school in Atta, a town about 40 km west of Djibouti city.

Ras Siyyan: 2 - 10 March 2013

Ali and Mike monitoring the migration of raptors during spring at Ras Siyyan, Djibouti

During 2-10 March 2013 our team made observations of the migration of raptors at Ras Siyyan.  Ras Siyyan is a volcanic cone in Djibouti, and is the piece of Africa closest to Arabia.  Ras Siyyan and Pirim Island form the Bab el Mandeb Straits, which are a significant bottleneck for soaring birds migrating along the Rift Valley flyway, the second most important flyway in the world.

We counted a total of 4562 migrating raptors.  Many of those could not be identified because they were too far away.  Of the identifiable raptors (3290), over 53% were booted eagles (Aquila penata/Heiraatus pennatus) over 35% were Egyptian vultures (Neophron percnopterus).  Egyptian vulture is an endangered species, whose population has declined in recent decades due to a range of causes including accidental and targeted poisoning, persecution, electrocution and disturbance.  Unfortunately, its decline and the reasons for it are mirrored in other vulture species throughout much of Europe, Asian and Africa.

Apart from the migration being dominated by the two species, it was also interesting that we saw no (zero) Egyptian vultures that were < 3 yrs of age.  This observation supports the theory that immature Egyptian vultures that eventually breed in Europe and Asia, spend their immature years in Africa.

Almost all our observations of migrating birds were made in the morning before 1100.  Typically, migrants would start moving at about 0800, but by 1000 soaring groups were disappearing from view both southward and upward.  We spend some afternoons trying to locate the migration, and only did so on the last day, when we found a stream of eagles flying southward above coastal hills about 20 km south of Ras Siyyan.  Despite our efforts we never did locate a point of embarkation and we suspect that the raptors just gained height and perhaps crossed along a relatively broad front toward Yemen.

Ahmed Hamadou, our local guide, talking to local fishermen who could not go to sea due to the heavy winds.

The Djibouti Egyptian Vulture Project 2013

During 28 February - 14 March we studied the migration of soaring birds (mostly Egyptian vultures and booted eagles) migrating between Africa (Djibouti) and Arabia (Yemen) over the Bab el Mandeb Straits.  The photo above is of Ras Siyan; about 20 km beyond it across the straits is Yemen.  The purpose of the study was to better understand the composition and scale of migration across the straits, and we also aimed to capture an Egyptian vulture and fit it with a satellite radio transmitter and follow its movements.  The effort was funded from a variety of sources:  The EURAPMON/European Science Foundation, Mohammed Shobrak at Taif University in Saudi Arabia, the Milwaukee County Zoo, the African Bird Club and International Avian Research.  The satellite tracking is a collaborative study with Hawk Mountain Sanctuary.

This blog will detail the effort and regularly post maps of the movement of the tagged vulture.  We aim for the blog to become a platform for conservation education, and will aim to link with a Djiboutian school.  If this proof-of-concept effort is successful, we aim to expand it by conducting more field work during the migration times (autumn and spring) and fit more birds with satellite transmitters.  So, "follow" us, visit the blog often and ask questions or comment on the effort.  We will try to respond to any questions and do our part in discussing the work.  As Djibouti is Francophone, some postings may be made in French.  You need only click on the Google Translate button above to switch (imperfectly) between languages.