171379 is in UAE

 

Lappet-faced vulture (ID=171379) in its nest before fledging. ©ESO, IAR.

Vultures are obligate scavenging birds, meaning they don’t hunt for live food; they have a number of physical, physiological and behavioural traits that enable them to survive.  They need these because the food that they eat (i.e. remains of dead animals) typically occurs at very low densities, spread over large areas.  To find enough food to survive and thrive, vultures typically fly over huge distances in search of food, enabled by their physical ability to soar over those huge distances using little energy by harnessing updrafts of warm air.

Movement of a young Lappet-faced vulture (ID=171379) during May – October 2022.  Green pin in far NW is the vulture's location on 14 October 2022. ©ESO, IAR.

Above is the map of a young Lappet-faced vulture that was fitted with a GPS tracking device (ID=171379) in May, just before it left its nest. Since then (almost 6 months now) it has travelled thousands of kilometres over a huge area, and in recent days it has gone “international”, visiting the UAE (Marmoom Conservation Area and near Hatta).  The movements of this bird may be particularly wide-ranging because this young bird is not yet old enough to breed, so is not yet tied to an area where it will breed. Click here to read an earlier post that details this vulture's ever wider ranging. 

Ever wider ranging by juvenile vultures

Movements of a juvenile Lappet-faced vulture in the first month after fledging.©ESO, IAR.

The process of becoming independent for nestling Lappet-faced vultures is a progressive one, much like it is with many species. Our tracking has illustrated this.  After tagging, the nestlings spent some days in the nest, then made short, then ever longer excursions away from the nest.  The map above shows the movement of a juvenile Lappet-faced vulture for the first month after tagging.

 At the beginning the young birds were mostly fed by their parents, but as they wandered more widely, they encountered food and fed themselves.  Over time they came to be entirely independent of their parents for the direct provision of their food.  The map below shows the same vulture from above, but during its 3^rd month after tagging.

Movements of a juvenile Lappet-faced vulture in the 3rd month after fledging.©ESO, IAR.

Once independent of their parents, vultures of all ages benefit from having other vultures and scavenging birds around because it helps them locate their food (dead things), which may occur only very rarely across huge areas.  In that way they are not really independent, but rather interdependent with the other scavengers.  The result is that, over time, vultures travel huge distance, especially during the non-breeding season. The map below shows the cumulative movements of a young Lappet-faced vulture until 5 October 2022 (4 months of tracking).

Movements of a juvenile Lappet-faced vulture during the first 5 months after fledging.©ESO, IAR.

Rehabilitated Lappet-faced vulture released.

 

A Lappet-faced vulture that was found unwilling to fly in June 2022. It was captured, treated and released ©ESO, IAR.

On 18 June 2022, an adult Lappet-faced vulture was found ill and unable/unwilling to fly.  It was amongst a mixed group of other Lappet-faced and Egyptian vultures at a water trough near the Wadi Sareen Reserve. With the help of the Environment Authority rangers at the reserve, the bird was taken into captivity and kept at the Environment Authority’s Biodiversity Centre in Barka.  Its health was monitored, and it appeared to recuperate to the point that we released it back into the wild on 30 June, having fit it with a GPS tracking device.  

During the first days and weeks after release we were a bit concerned because the vulture did not move very much.  We even considered taking it back into captivity.  Happily, since those early days it has been wandering ever more widely.  Maps below.

Movements of a rehabilitated Lappet-faced vulture (ID=171381) during the first week after release on June 30, 2022. ©ESO, IAR.

Movements of a rehabilitated Lappet-faced vulture (ID=171381) during 30 June - 22 September 2022. ©ESO, IAR.

Besides the happy outcome, this story also highlights other things… First, it reminds us that we don’t understand well the threats facing vultures, and how to address them.  The bird in this case may have been poisoned.  If that is true we have no idea about the type of poison or how the vulture came to consume it.  Second, at times injured and sick wildlife are found by the public.  It is important that the safety of both the animal and the helping human are kept in mind.  If you find an injured or sick vulture or other raptor, try contacting the Environment Society of Oman or the Environment Authority.  You can also leave a message on the blog, and with luck we’ll see it soon and get back to you, with some advice. 

You can read more about the work we are doing on Lappet-faced vultures by visiting ESO's Facebook page (here).  And here is a video about the work 

Lappet-faced vulture nestling found dead on the nest.

Lappet-faced vulture nestling before (note the shiny, open eye) and after (desiccated eye and dried body parts) its death from an unknown cause. ©ESO, IAR.

As mentioned in a previous blog (here), one of the nestling Lappet-faced vultures we fitted with a tracking device died on the nest.  

The way that transpired was: we (Environment Society of Oman vulture study workers and Environment Authority staff) visited the nest, and fitted the chick with a tracking device on 11 May.  All was fine.  We set up a trail camera to monitor the nest. The tracking device provides not only location data, but also information on acceleration in three dimensions, so by monitoring that we can determine when the device is no longer moving.  Of course, a non-moving device suggests that the bird might no longer be alive or the tag has fallen off.  

Twenty-three days after fitting the transmitter, the tracking data suggested that there might be something wrong, a team when out to the nest and found the chick dead.  The team collected the chick and took it to a vet for a necropsy.  Unfortunately, the extreme heat had caused the carcass to deteriorate, and the results of the necropsy were inconclusive.   We had also set up a trail camera at the nest, but it showed the adults (or at least one of them… we couldn’t tell because birds can’t be recognized as individuals… at least, not by us) visiting the nest regularly.  However, the camera memory filled and we had no images from the likely time of the death of the bird.

We really don’t know the cause of this bird’s death.  It could have been a natural event, but when we fitted the device, the bird seemed in good health (photo above).  It could have been that the parents brought in some food that was somehow contaminated, and that poisoned the nestling.  Although bird parents can abandon their chicks if disturbance is too great that does not seem to be the case here because the adults were photographed arriving at the nest after we fitted the tracking device.  It is also possible that one or both of the parents died for some reason (we know of Lappet-faced vultures being electrocuted nearby), and there was not sufficient food for the chick.  Like I said, we simply don’t know.  

Last year a similar mysterious death of a seemingly healthy Lappet-faced vulture nestling occurred in Dhofar.  Because that bird was not fitted with a tracking device, we only learned of its death after some weeks, and by then had no chance of guessing at the cause.  At least one goal of our work is to better understand what threats (e.g. disturbance, poisoning, and persecution) face Lappet-faced vultures in Oman, and work to lessen those threats.

Update on tracking of Lappet-faced vultures

 

Movements of a juvenile Lappet-faced vulture during 5 May - 19 June 2022. (Yellow = 5-19 May, Blue = 20 May-3 June, Red = 4-20 June) ©ESO, IAR.

In May 2022, we fit GPS-GSM tracking devices to four nestling Lappet-faced vultures in the Hajar Mountains.  Here and here are earlier blogs about that work.  The tracking is part of a larger study that has been funded by the Disney Conservation Fund and the Anglo OmaniSociety.  The tracking devices were provided by Hawk Watch International.  The Environment Authority of Oman provided field support and the permits to do the work.

First off, the bad news… A couple of weeks after tagging, the signal from the tracking device suggested that one of the birds we had tagged was no longer moving on the nest.  At that time it was too young to have fledged, so we visited the nest, and found that the nestling had died.  A future blog (here) will provide details, but the short story is that we do not know why it died, though camera trap images show it was being fed by the parents, and there was no evidence that the tracking device played any part in the bird's death.  Like I said... the long story will be posted in a later blog post, so come back later to read about it.

Now the (so far, very) good news…  The three remaining nestling Lappet-faced vultures that were fitted with tracking devices all fledged successfully, and since then have dispersed ever farther from their nest sites, although the nest sites seems to occasionally draw them back.  Below are maps of the three birds we have tracked during the period May – August.  At the moment we refer to these birds by their tracking device ID number.  It’s not very imaginative, and perhaps we’ll seek to name them.

Future blogs will update those data, so come back and see what has happened.  You can of course subscribe to the blog and get notifications about blog updates.  Also, please let you friends and networks know about the blog, and leave any comments you might have.

Movements of a juvenile Lappet-faced vulture (ID:171379) since fledging. ©ESO, IAR.

Movements of a juvenile Lappet-faced vulture (ID:190560) since fledging. ©ESO, IAR.

Movements of a juvenile Lappet-faced vulture (ID:191098) since fledging. ©ESO, IAR.

Vultures are fledging

A nestling Lappet-faced vulture.

As you may know from our previous posts (here), we are tracking juvenile Lappet-faced vultures via satellite.  As with many animals, the process of maturing is a gradual one for Lappet-faced vultures.  After hatching they may stay in their nest for a full 4 months before taking their first flight.  After that they develop their flying skills, but are pushed to do this rather quickly because they must search huge areas for their food.  The map below is of the movements of a vulture we marked in its nest just before its first flight.  Below are a couple of maps illustrating how the vulture has ranged farther and farther from its nest, as time has passed.  It is pretty amazing to me that a bird that has only been flying for about a month can travel so far!

Map of movements of a juvenile Lappet-faced vulture during 5 May - 19 June 2022. (Yellow = 5-19 May, Blue = 20 May-3 June, Red = 4-20 June) ©ESO, IAR.

Zoomed-in map of movements of a juvenile Lappet-faced vulture during 5 May - 19 June 2022. (Yellow = 5-19 May, Blue = 20 May-3 June, Red = 4-20 June) ©ESO, IAR.

The gradual process of maturation continues after that first flight, and it is only after 5-6 years that the vulture will become sexually mature, and may breed.  More about that in future blog posts, so check back for updates.

Tracking a Lappet-faced vulture

A nestling Lappet-faced vulture that has been fitted with a GPS-GSM tracking device.  Ali Al Rasbi is the one without the feathers, and is a member of ESO's vulture team.  ©ESO, IAR.

In May 2022 the ESO vulture team, Environment Authority employees and volunteers from the public fit GPS-GSM tracking devices to nestling Lappet-faced vultures from the Hajar Mountains.  The nestlings were found by our team and cooperators earlier this year, and we have been monitoring their progress as they grow.  When they were old enough, but before they had flown (about 100 days old), we fit some of them with tracking devices, and placed them back in their nest.  Some days/weeks later the nestlings take their first flight ("fledge"), and we are able to follow their movements with the help of the trackers.

The tracking devices weigh about 50 grams, small enough to cause no harmful effects to the vultures (which weigh 6.5 - 8 kg!).  The devices are attached using a custom-made, Teflon, pelvic harness that does not interfere with flight.  Getting the fit right is important - too tight and it will injure the bird, too loose and it will hang from the bird and may affect flight.  In future blog posts we'll explain more about the devices and tracking, and you'll learn as we go along.

The solar powered GPS-GSM tracking device on Lappet-faced vulture 17139.  The bird's head has been covered to keep it calm.  © ESO, IAR.

Below is a map of movements of a young Lappet-faced vulture fitted with a tag on 5 May 2022, first as it sat on then nest, and then as it made more and wider excursions from the nest during its first flights.  Currently it has the romantic name of "171379", which is the identification number of its tracking device.  As you can see, at the moment most of the locations are clustered in the north.  That is where the nest is.  You can also see that it made a rather long excursion to the south (the distance between the nest and the location farthest south).  As time passes, this bird will expand its ranging, and (assuming it survives), will cover vast areas in search of its food: rather large dead animals.

Movements of a juvenile Lappet-faced vulture during 5 - 31 May 2022, when the bird fledged and started to move more widely in the area around the nest. The arrow indicates its last location.  The distance north to south is about 15 km. © ESO, IAR.

If this is your first visit to the blog, then you might want to look at our first post (here) for some background.  In the coming days, weeks and years we'll be posting about other vultures being tracked, and about the biology, ecology and conservation of Lappet-faced vultures in Oman.  So, come back every so often or follow us with the button in upper right corner, and tell your friends and family about the blog.  Also, comment or ask questions in the comments box below.