The Ugab Pride

An adult male lion ("Miles" or Xpl-16) of the Ugab Pride was selected as the ideal candidate for a GPS collar. He was first radio-collared in May 2001 and has been monitored ever since. On 23 April 2008 he was immobilised and fitted with the only Satellite GPS collar.

Known home range of Xpl-16 prior to fitting the Satellite GPS collar
Fitting of the Satellite GPS collar

Efforts to dart and radio-collar new Ugab males
A marathon effort was required to locate and dart one of the lions that killed Xpl-16. Their tracks were followed for hundreds of kilometres across the broken Ugab terrain and eleven consecutive nights were spent sitting-up and waiting for a chance to dart them. The tracks of the two males were measured and studied in detail, and it was possible to distinguish between the two individuals by the size and shape of their tracks, and by the manner of walking (foot placement & sequence). On the 11th night a sound playback of the roar of “Miles” was used. This appeared to have tricked the two males. They charged towards the speaker, arguably looking for “Miles” (the lion they killed a week before), and gave me an opportunity to dart one of them.

Comparing the spoor and pads of the right hind foot
Sound file of Xpl-16's roar

00:30 (64Kb)

Xpl-16 died on 15 August 2008
On 15 Aug 2008 the satellite GPS collar of Xpl-16 reported that the mortality beacon inside the collar had been triggered. The mortality beacon was programmed to activate after 150 minutes of no movement. Upon receiving the message an effort was made to locate the lion and investigate. However, much of the lower Ugab River was not drivable because of the high rainfall earlier in the year and the terrain outside the riverbed was extremely rugged. After five days of getting stuck, trying different routes, and building river crossings and pathways over gorges, the death of Xpl-16 was confirmed. Two full days were spent studying the tracks and other signs to reconstruct the events that caused his death. It was not an easy task because several days had passed and there had been strong east winds.

Images of the rugged terrain
First view of the carcass of "Miles"
Closer inspection to determine the cause of death

Cause of Death - Conclusion

1) On 10 Aug 2008 Xpl-16 killed an oryx and was feeding on it.
2) Sometime between 11 and 13 Aug 2008 a group two adult male lions arrived at the scene.

3) An extensive territorial battle between Xpl-16 and the new males enfolded.

4) At one point during the battle, Xpl-16 succeeded in displacing the males and chased them >1 km south of the Ugab River.
5) But the males returned and during the night of 14th Aug, got the better of Xpl-16.

6) Xpl-16 tried to get away from the males by running up a near-vertical cliff (see illustration below).

7) One of the males caught up with him on the cliff - 20 metres above the ground – and they came crashing down.
8) There is evidence of an extensive battle: deep scrape marks and blood stains in the soil.
9) Xpl-16 was mortally wounded during this battle and died sometime during the late afternoon on 15th Aug 2008.

Signs of the battle in the sand
Xpl-16 fled up cliff (white arrows). Caught by males (X). Falling to ground (red arrow).
Chunks of blood-drained sand
Xpl-16 lay in the shade (right) earlier on 15 Aug.
Extensive abdominal wound - notice brand
Collecting necropsy samples

Chronology of NEWS entries

27 Aug 2008: Killer lions hoodwinked. A couple of days ago, I recalled filming “Miles” roaring in the Springbok River, and decided to try and trick the lions. Similar to human voices, the roars of lions are unique and they recognise different individuals. I captured the sound file on the computer, cleaned it up with sound editing software, and was ready to con the lions into thinking that “Miles” is still alive. Shortly after midnight this evening, the ploy paid off when the two male lions responded to the sound playbacks from several kilometres away. They roared continuously and approached the vehicle aggressively. I was able to dart one of the lions and fitted a GPS collar (see above for more details & listen to the sound file).

20 - 26 Aug 2008: Hot pursuit. The unexpected death of Xpl-16 ("Miles") has left a vacuum in the Desert Lion study. Not only did the satellite GPS collar provide high quality data on the movements of the Ugab Pride, but also “Miles” was the only radio-collared lion. This is a significant loss because the Ugab Pride occupies the southern frontier of the Desert lion distribution, and they are thus most likely to disperse, in search of new territories. It is essential to capture and radio-collar at least one of the new lions, before they disappear in the vast and broken Ugab terrain. The best technique under these conditions is one of tracking their spoor in the daytime to try and catch-up with them, and then using sound playbacks and bait to attract them at night. Including this evening, I’ve sat up for 10 nights, and covered hundreds of kilometres following their tracks, without seeing or even hearing a lion.

Lion A - right hind foot.
Search for the lions west of the Brandberg.
Lion B- left hind foot.
Finding new routes whilst tracking the lions.
Distribution of the nighttime calling stations, along the Ugab River (map = 100 km across).

15 - 21 Aug 2008: Ugab male "Miles" died. On 15 Aug the email sent by the satellite GPS collar of Xpl-16, the Ugab male lion, revealed that the mortality beacon inside the collar had been triggered. I dropped everything and set off to investigate. However, much of the lower Ugab River was not drivable because of the high rainfall earlier in the year and the terrain outside the riverbed is extremely rugged. At one point I considered walking (32 km), but I was not convinced that “Miles” was dead; the mortality beacon had stopped and it was possible that the collar was faulty. After five days of getting stuck, trying different routes, and building river crossings and pathways over gorges, I finally reached the destination. Disappointingly the collar was not faulty and I located the carcass of Xpl-16. Another two days were spent studying the tracks and other signs to reconstruct the events that caused his death.

Real-time animations
The movement patterns of "Miles" (Xpl-16) in the Ugab River are presented below using Flash animations to represent real-time events. Click on the PLAY button to start the animation. The timeline is constant at 2.5 seconds per day (24 hrs). When the red dot moves quickly across the screen, it accurately represents the speed at which the lion covered vast distances. A summary of the actual distances traveled per day is listed in a separate table.

Period: 10 - 15 August2008

Date
Distance (km)
10 Aug 2008
2.4
11 Aug 2008
0.5
12 Aug 2008
0.9
13 Aug 2008
2.5
14 Aug 2008
0.7
15 Aug 2008
0.1
Xpl-16 died
   
   
   
   
   
   
   
   

Period: 26 July - 9 August2008

Date
Distance (km)
26 Jul 2008
3.6
27 Jul 2008
0.8
28 Jul 2008
0.9
29 Jul 2008
9.4
30 Jul 2008
24.0
31 Jul 2008
3.9
1 Aug 2008
3.7
2 Aug 2008
13.0
3 Aug 2008
4.1
4 Aug 2008
13.5
5 Aug 2008
1.4
6 Aug 2008
22.2
7 Aug 2008
19.1
8 Aug 2008
15.4
9 Aug 2008
21.4

Period: 11-25 July 2008.

Date
Distance (km)
11 Jul 2008
0.3
12 Jul 2008
0.1
13 Jul 2008
0.1
14 Jul 2008
5.2
15 Jul 2008
9.3
16 Jul 2008
29.7
17 Jul 2008
25.8
18 Jul 2008
2.5
19 Jul 2008
0.7
20 Jul 2008
5.6
21 Jul 2008
2.2
22 Jul 2008
0.3
23 Jul 2008
0.2
24 Jul 2008
0.3
25 Jul 2008
0.2

Click here to view more animations of Xpl-16.