Nov 2011: Tagging Okulunu with a GPS/GSM unit

Bruno Nebe arrived in Mundulea on the evening following the capture of Okulunu, ie Nov 7th 2011, and managed handling of the animal with Tim. Its weight was taken, being at 13.1 kg i.e. close to its previous recorded weight in August 2011 of 13.5kg, see previous post. With such a large and strong pangolin, handling is difficult, as if the animal is lifted by its tail it scythes in a twisting motion which makes its sharp scales dangerous. Some attempts were made to photograph its underside to sex it (we are now 95% sure it is male, rather than female as reported previously), and some unsuccessful attempts were made to take blood samples with a surgical needle inserted under its scales but blood could not be drawn and the attempts were abandoned rather than distress the animal. Some mite and small tick infestations were noted between the scales which are not unusual, otherwise the pangolin seemed to be in a very good condition.

(photos in this post were taken by Emiel de Lange)

Meanwhile the combination unit's electronics was programmed by Paul to set both its GSM and GPS multiple activity time windows and sampling rates, and then test its functioning, e.g. the unit's GPS data logger and the ability to interrogate the unit with a phone call and receive its GPS coordinates via an SMS. Four windows were setup when the GSM unit would be on at known times for limited periods and the GPS logger set up to take readings every 2mins just during the night to conserve its limited battery life. The unit's casing had had some extra protective and streamlining rails moulded using Pretty's putty and was sealed with silicone grease.

A dorsal scale behind the animal's shoulders was selected for attachment of the extra GPS/GSM combination tracking box, 3 scales forward of the scale carrying its small RF transmitter tag. Two small holes were drilled through the scale, ensuring the animal was protected under the scale during the process to take the two attachment bolts and locking nuts from which the box trails. After clipping small pieces, which were kept for DNA analyses, off the neighbouring scales to ensure that the scales' movements were not restricted by the device, the extra tracking box was attached successfully by Bruno and Tim, using long-nosed pliers and spanners. Okulunu was then taken back to the GPS coordinates of its capture and re-released on the friendly neighbour's property- within 24 hours of its capture very early in that morning of the same day, Nov 7th. Finally turning in to sleep late that night, Paul was able to phone the combination unit and receive an update of its GPS coordinates including signal strength and then unit's battery level from his bed! This must be a first in pangolin tracking!

The following night Nov. 8th, after a heavy thunderstorm and rain heralding start of the wet season, Emiel and Paul decided to revisit Okulunu to watch from a distance- the first chance they had both had to observe a pangolin foraging in its natural habitat. By 10:30, the RF tag's signals were detected using the Yagi aerial, and when the combination device's next GSM window opened, Paul was able to activate SMS transmissions carrying Okulunu's GPS coordinates. These showed the animal was moving. Entering the coordinates into a Garmin GPS as a new navigation waypoint, then walking direct to Okukulu was easy, using the Yagi for the last 10m of animal location. This demonstrates the potential of the prototype system for pangolin tracking work and behavioural observations in the wild.

Emiel and Paul spent 2 rare hours that night watching the pangolin - the culmination and reward for all the weeks of searching for Okulunu and all the iterations of development and testing time spent on the combination electronic device. Seeing a pangolin foraging with its long pink sticky tongue searching out ants and hearing the strange scaly sounds as it walked were fascinating. Closer than 5m and the animal stopped moving, but it seemed undisturbed if observed from beyond 10m. Reluctantly returning to the Mundulea farmhouse to sleep, a further SMS with a location update was obtained that night.


With Paul's field trip now over, he had to prepare to return to the UK. For a few days subsequently, SMS updates to Okulunu's coordinates were obtained on different phones, the animal remaining within about 2km of its release spot. After that unfortunately the GSM phone in the unit did not respond to calls - either probably because it was out of MTC cellular coverage (which is very patchy in this region SE of Otavi), or possibly because of damage to the unit or moisture from the heavy rains that followed.

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