11.12.10

Background on Pangolins

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Bruno Nebe talks about pangolins and our project in this YouTube video interview.

Pangolins, sometimes called scaly anteaters, are very unusual animals. These toothless mammals are covered with hard overlapping scales, walk on their hind legs counterbalanced by a large tail and feed exclusively on ants and termites. The prey are dug out with their sharp claws and caught on a very long sticky tongue. (Watch this National Geographic video) The young are carried on the mother's back. Usually nocturnal, they sleep most of the day in burrows made in the ground, or take up residence in the dens of other animals such as the aardvark. When threatened, pangolins curl into a armoured ball, protected by their sharp scales. (see http://en.wikipedia.org/wiki/Pangolin )
(Click on any photo to see an enlarged version) 
Eight different pangolin species can be found across Asia and sub-Saharan Africa. Poaching for the illegal wildlife trade or for Chinese medicine products and their habitat loss have sadly made these creatures one of the most endangered groups of mammals in the world. In June 2010, nearly 8 tonnes of more than 2000 frozen pangolin and 2 tonnes of their scales were seized by Chinese customs officials from a boat destined for mainland China, see article in The Guardian)
(For more background on this terrible trade, see http://www.savepangolins.org/conservation and support the Save Pangolins organization on Facebook)

Being nocturnal and highly secretive, these elusive solitary mammals are thus difficult for scientists to study in the wild. Attempts to keep them in captivity invariably fail, because of their prodigious appetite for enormous numbers of live ants and termites - and their abilities as escape artists! Estimates of 70 million insects consumed per year have been made (see Bush Warriors, 19th Nov. 2010) Many mysteries therefore remain about their behaviour and habits: our ignorance hampers conservation efforts. For example, there are no detailed studies on the population levels, ecology, or life history of the Sunda pangolin, Manis javanica. Meanwhile, little is known about the current distribution and range of the various other pangolin species.
Sunda Pangolin, photo taken by Piekfrosch, May 2006 from:
http://en.wikipedia.org/wiki/File:Pangolin_borneo.jpg
Our own focus in Namibia is on the Cape Pangolin, or Temminck's ground pangolin (Taxon Manis temminckii, Smuts 1832, of the Manidae family, Pholidota order): see this excellent video plus species summary or watch this BBC video. The Cape pangolin is less threatened than the four Asian pangolin species but remains rare with decreasing numbers, because of its value in the Chinese and Traditional Medicine illegal markets, chemical insecticides and electric fences. (Its entry in the CITES RedList 2000 by the Pangolin Specialist Group allocated it the rating Lower Risk - near threatened (LR/nt - ))

Manis temminckii is one of the least studied types of pangolin, despite its widespread occurrence throughout southern and eastern Africa. For example, there are no detailed studies on the population levels in dry savannah ecologies or of the life histories of the Temminck's ground pangolin - i.e. its traits remain undocumented and basic ecology remains to be researched. One of the few people working on this species is Jonathan Swart, based in the Sabi Sand Wildtuin next to the Kruger Park, South Africa, see the Kruger Times article.

Pangolins are ancient creatures. Their ancestors are thought to have been members of the suborder Palaeanodonta, which diverged from the ancestral edentates some 60 million years ago, see the linked article. These small, armorless animals rapidly became extinct but their successors evolved into the order Pholidota. Today, this order contains one family, the Manidae, with eight living species. Four species are found in Africa and three in Southeast Asia. The widely accepted classification of the seven living pangolin species recognizes one genus (Manis) and five subgenera (Manis, Paramanis, Phataginus, Smutsia and Uromanis). The earliest fossils of the Cape Pangolin species itself date back 40 million years, see pages 112 & 113 in: The Complete book of Southern African Mammals, compiled by M. G. L. Mills & Lex Hes, Struik Publishers, Cape Town, 1997.

Our Research Project's Goals

The motivation for gathering data on the behaviour, habitat and survival strategies of the Cape pangolin in different environments is that an improved understanding of this mammal can help its conservation. For instance, a better understanding of this unique animal can help in putting together information sheets for the general public which can help conservation of the pangolin in its natural habitat.

Given the enormous quantity of ant and termite prey that one animal can consume, then despite its rarity and infrequent sighting, the elusive pangolin must play a significant role in fragile semi-arid ecological systems. A better understanding of the Cape pangolin can help our knowledge of other pangolin species.

In previous research, radio-telemetry tags, infrared-triggered cameras and intermittent visual observations have been used to find out more about pangolin behaviour. These techniques, as compared with automatic GPS or satellite location logging, severely limit the continuity and type of data that can be obtained on the animals’ movements, activities and locations. Moreover, as the animals are nocturnal, then tracking their movement through the bush at night using short-range radio telemetry is both difficult in a harsh terrain and potentially dangerous because of the presence of other game, especially predators!

The goals for our pilot study are to establish research protocols and to develop better tracking and relocation device combinations that will work for the pangolin without disturbing the animal, but will deliver the data needed over a reasonable period. Our pilot study has its research base at the Mundulea Nature Reserve.
Our immediate objectives are to:
  • Design, test and prove methods for tracking pangolins using special-purpose GPS-logging devices, augmented by RF telemetry and/or cellular GSM+GPS location-interrogation techniques to aid recapture e.g. to harvest the GPS logged animal data and change the batteries of the devices.
  • Get experience in the capture, device attachment/RF tagging and re-release protocols which are of least disturbance to the animal. (We do not plan the permanent capture or killing of any animal.)
  • Collect small-sample data on 2-4 animals’ activity and location patterns, eg to improve the initial estimate of the hours of its night activity, in order to improve the efficiency and duration of further trials.
  • Prepare a initial correlation between pangolin locations/behaviour and the terrain, habitat and its prey species
  • Train local Namibian staff on procedures for visual identification of pangolin tracks, animal capture, tagging, release, re-capture for data download or battery exchange, re-release and data analysis.
  • Trial the use of movement or infrared-triggered cameras at active pangolin dens
Our longer-term aims include:
  • Finding ways to successfully release previously captured animals (mainly by poachers)
  • Assessing the suitability of techniques to gather other data e.g. on body movements and posture, temperature etc.
  • Using the results of the pilot to plan a longer, more extensive longitudinal investigations of the behaviour patterns, movement and habitats of more animals over a larger region of Namibia.
  •  Attempting to correlate the pangolin's foraging strategies with the seasonal activity and location of its prey species
  • Comparing our results with previous South African and Zimbabwean studies of the pangolin (They were conducted in high rainfall areas with a softer terrain for tunneling and where there are different predators.)
  • Discussing the results with other experts, publishing our findings and promoting our tracking and relocation techniques. The latter might find application with other, more endangered species of pangolins, e.g. in Asia, or indeed for studies of other animals

Research Challenges


The technical problems in designing a tracking solution for pangolins include:
  • The pangolin’s body shape, its hard sharp scales and movement through dense rough undergrowth or through tight hard-earthed burrows mean that any devices must be very robust and suitable attachment is difficult – collars are unlikely to stay on.
  • Attachments, eg RF telemetry tags screwed or glued to the rear dorsal scales should not restrict free movement of the overlapping scales, one over each other when the animal moves or rolls into a protective ball. (c.f. Catchco Africa’s illustrations of an RF tag being attached to a pangolin)
  • The animal spends most of its day underground in burrows or dens, out of cellular GSM network connection or GPS satellite signal acquisition, usually emerging only for a few hours at night. Device batteries should be less than say 5% of the animal’s body mass (3-16kg) so that the animal is not hampered, thus limiting battery capacity. As most electrical energy is consumed in re-acquiring a GSM network connection or in a new search for GPS satellites, then any tracking device’s lifetime will be too short if the device is constantly searching for radio connections whilst the pangolin is sleeping in a burrow.
  • The range of small RF telemetry tags is limited to about 1-2km. Manual location of a pangolin, following it at night through the bush in a harsh terrain without disturbance using the usual Yagi antenna directional location equipment is difficult and potentially dangerous.
  • If a GSM connection is used to transfer live GPS location data to a base station, then the cell coverage of the pangolin’s territory will be incomplete, as the signals to or from a low-lying animal are obscured by rocks or hills even when the pangolin is moving on the surface.
  • Tri-axial accelerometry offers potential for this application (limited again by battery capacity) and can gather additional data as well as just location fixes, e.g. on patterns of an animal’s movements and posture. However, such devices are still being developed and are not yet readily available. They require considerable customization for specific species, occasional GPS location fixes for the dead-reckoning location calculations and subsequent pattern analysis of the recorded accelerometer data.

Mundulea - An Ideal Research Bed

The Mundulea Private Nature Reserve in the Otavi mountains is roughly 120 square kilometres of prime Montane bushveldt set in the unspoiled Karstveld south east of Otavi.  Bruno Nebe of Turnstone Tours (see http://www.turnstone-tours.com/), established Mundulea Nature Reserve five years ago to conserve and protect the huge diversity of fauna and flora which thrives in this unique biosphere (see http://www.mundulea.com/).
Mundulea's dolomite, limestone and marble hills are millions of years old. They are riddled with caverns and pot-holes, deep gorges and underground lakes. There are ancient Leadwood trees, Marulas, Wild Fig, White Syringa, Dombeya, Mearua, Carrot trees and Nettle trees. There are also countless species of aloe, acacia, fern, grewia and combretum. The farm itself is named after a beautiful purple flowering bush Mundulea sericea, favourite food of the Eland and Kudu, and said to be possessed of healing and magical powers.











Antelope species include large herds of Eland, Wildebeest, Kudu and Oryx. Hartebeest, Waterbuck, Dik Dik, Steenbok, Duiker and Warthogs are common, whilst Giraffe and Springbok - once were plentiful in this area - are gradually being reintroduced. Recent arrivals are the endangered Black Faced Impala, Hartemann's Zebra, Tsessebe and a small group of Southern Angolan Roan. Often-seen predators include Leopard, Cheetah, Hyena, Honey Badgers, Jackal, Serval and Lynx. Sightings of Aardvark, Aardwolf, Bat-eared foxes, Black Mongoose and of course rare spottings of Pangolin are possible.

One of the most interesting animals on the nature reserve is a black rhino bull called ‘Hooker’. He is one of seven black rhino at Mundulea and is the last remaining example of the sub-species Bicornis chobiensis. He is central to Mundulea’s main objective: to respect bio-diversity and give breathing space - and breeding space - to Namibia’s rare and endangered sub-species. Without serious and accelerated protection, animals like Hooker, the Southern Angolan Roan and the beautiful Black-Faced Impala (an indigenous sub-species uniquely suited to Namibia), will be lost to the world in the near future.

A number of research studies have started in Mundulea, providing us with a growing body of knowledge on this biosphere, its geology, habitats, flora and fauna, animal, insect, bird and plant interactions. This makes for an ideal research context to understand more about the pangolin's territorial and seasonal behaviour, its preferred habitats and its relationships with other pangolins, predators or with its own ant and termite prey, which in turn reflect the environment.

Some Tracking Technology Options

The Namibian Ministry of the Environment and Tourism (MET) has formally approved our application for permission to conduct this research and to release animals that were previously confiscated by MET, PRU or police on the Mundulea Nature Reserve for this study.

In the pilot, we are seeking to gather the following basic data on a few individuals:
  1. Daily foraging periods of activity and sleep
  2. GPS locations, track, speed and range of movement during (nocturnal) activity
  3. Photographs and fauna samples of locations frequented by the pangolin (determined from the GPS data or TF telemetry and animal trackers)
  4. Posture data (if possible)
Our basic procedure will involve:
  • Location of a few pangolin specimens (via manual trackers) on the Reserve
  • Tagging 2 dorsal scales with both a custom designed ‘combination’ GPS unit and also a more standard RF telemetry transmitter.
  • Animal release, preferable where captured.
  • Real-time occasional monitoring of animal’s location by interrogation of the ‘combo’ unit’s GPS system over a cellular SMS connection, or as a back-up manually, via RF telemetry using a Yagi aerial
  • Recapture of the animal when device batteries are low, hopefully after about 2weeks to upload GPS logged data and change device batteries
  • Final recapture to remove our logging devices and to release animals unharmed.
A few RF telemetry tags with 1-2km ground-level range have been purchased from Biotrack (see www.biotrack.co.uk/ , now a part of www.lotek.com), specially adapted for attachment to a pangolin scale with an extra ground plane antenna added to increase range and a longer-life battery, see photos below of their single-celled PIP3 two-stage transmitter with AG386 (magnetic switch attached) and of longer life, more powerful TW-3 transmitters that have now been designed for our pangolin project and produced by Biotrack, see below.










Sketches of two possible attachment options suggested by Sean and Sarah at Biotrack are below.








A ‘combination’ GPS-logger plus GPS-SMS real-time data reporting unit has been specially designed with our guidance for this application and the constraints of attachment, by an electronic expert in the specialist company CatTraq (http://www.mr-lee-catcam.de/cattraq/ ), see photo below and one attachment option. This combination unit’s design for pangolin tracking has been arrived at after many iterations between Paul and the electronics expert, Juergen Perthold.
 

Start of Fieldwork Sept. 2010, a visit to Narrec

After extensively testing the GSM and GPS functions of the three 'combination' tracking units made by Juergen Perthold, Paul arrived in Windhoek on September 17th for a first preparatory project visit.

An introductory visit was paid to Narrec, the Namibia Animal Rehabilitation Research and Education Centre just North of Windhoek run by Liz Komen. Liz has a special relationship with the Ministry of Environment and Tourism.The primary focus of the Non-Profit centre is to provide professional care and rehabilitation facilities for injured, orphaned and misplaced wildlife in order to facilitate their release back into the wild. (see http://www.orusovo.com/narrec/ ) 











Their work often involves birds of prey, some of which Paul was shown by volunteer Narrec staff, Rose and Marsha during a tour of their aviaries.











Liz also has many years of expert experience in relocating and releasing pangolins that have been given into her care after being rescued from illegal possession or after injury: over the past 20 years Narrec has received about 40 pangolins. In each case the animals were confiscated from very badly managed environments. She has also been alerting the public of the threats to the pangolin species. (Read her article on 'Pangolins and TRAFFIC' )

Paul discussed the plans for our Pangolin Research project with Liz and her husband, Joris, learning more about the background on pangolins in Namibia. The situation with respect to their mistreatment or killing for sale to traditional healers has deteriorated. Sadly, they fetch a high black market price reputed to be of around N$10k (~ $US1500).

After a very constructive meeting, we have agreed to collaborate closely with Liz during our research project, e.g. on tracking rescued animals and especially later in improving the education about pangolins and getting them to be more respected.

Basic Training in RF Telemetry

Using a Yagi directional antenna on a radio receiver tuned to the frequency of a small RF transmitter attached to an animal or bird is a standard approach for tracking wildlife. However, the method still requires some practice to locate the transmitter at the limits of its range. Paul became familiar with the equipment, using the 3 lower-power PIP tags purchased from Biotrack which have an extra ground plane antenna to increase their range. Some range experiments were done, with the RF tags at ground level on a rock, successively walking increasing distances on the flat from them with the Yagi and receiver, but also each time climbing the hilly outcrop in the centre of the South part of Mundulea (see view from the hill below): good exercise!











The detectable range obtained of about 400m on the flat was disappointing, given that pangolins can amble further distances in a day (or night!). Of course, slight rises in the terrain, rocks or stones will block the RF signals near ground level. More useful detection ranges of up to about 2km were found to obtainable from the hillside and top. (Subsequently, we have had longer-battery life, increased range TW-3 tags made by Biotrack for our pangolin application) Like other RF communication methods, a pangolin would have to be above ground, out of its usual daytime burrow to be detected this way.

The custom electronics tracking 'combos' which Juergen has specially developed allow one to interrogate the unit's GPS location over a cellular GSM network, getting the coordinates back via an SMS message (That is, if the unit is above ground, GPS signals have been acquired and the GSM network has been found). Two Namibian mobile network providers, MTC and LEO, reach Mundulea. However, their coverage of the Reserve is unfortunately patchy. Areas with better mobile reception were therefore investigated. The functioning of 3 combos tested out well with both MTC and LEO SIM cards inserted, having turned off the SIM cards' locking codes.

Pangolin tracking in Mundulea- expert assistance

Pangolin tend to be solitary, one individual ranging over several sqr. km and their spoor are hard to track through undergrowth, as they walk on two legs, lifting their tail off the ground most of the time. Rare traces of tail marks and their circular paw pads we think we found later are shown below:

 









Places where they have scratched out ants or termites to eat are more characteristic, showing the neat marks of their claws and perhaps a trace of their tail when it has been used to counterbalance the digging.

However, even these feeding sites can be difficult to distinguish from those of other animals such as honey badgers or porcupines, and their recency is difficult to read unless you are an expert in tracking. We therefore decided to engage a San Bushman game tracker to assist in mapping out some preferred pangolin territories in the Mundulea reserve, hoping of course to capture a specimen for tagging.

After an 800km round trip back to Windhoek to rent a town car, Paul drove from Mundulea to the Nyae Nyae Conservancy Office in Tsumkwe to pick up an expert tracker there who had agreed to help us in the hunt for pangolins. Driving distances in Namibia are always large. The remote community of Tsumkwe near the Botswana border lies about 390km from Mundulea, the last 250km being the dreaded C44.










This 4hr long straight gravel road due East to the border needs quite some patience and concentration with only a 2-wheel drive prone to sliding. (In two round trips to Tsumkwe, Paul only came off the road once, fortunately without damage or injury!). At Tsumkwe, the San Bushman tracker, !ho ||nani (John Nani) from the nearby village of Da||ua was met at the Conservancy Office.  There was just enough time before sunset to drive 40 km back on the C44 and another very tricky 40km North on a soft sandy road to the the Nhoma Camp to surprise an old friend Arno there, watch some of the nearby Bushman villagers dancing around the campfire and enjoy the hospitality of one of Arno's palatial tourist tents for the night.
Nhoma San Bushmen
!ho ||nani (John Nani)











The following day, Paul returned - with only one puncture - to Tsumkwe, to collect John for the long drive back together to Grootfontein and then back to Mundulea. Luckily, there was still some petrol at the only fuelling station in Tsumkwe to fill up for the C44 return run.
 


Mapping Pangolin Feeding Sites in Mundulea

A latitude and longitude-gridded GPS map of the Mundulea Reserve, incorporating accurate boundaries, roads and feature coordinates, both from GoogleEarth and from another ongoing study on acacia species was prepared by Paul before the preparatory work in Sept 2010. This is very useful for planning activities on the pangolin and other research projects.

Using Bruno's bushcamp near the hill in the centre of the southern part of the Reserve as a base, walking surveys of likely pangolin habitats were planned. We of course hoped to track down an animal for RF tagging, but also to map out the territories where pangolin ant and termite feeding traces could be found, assessing their recency and activity levels. Four sandy zones or 'islands' between more rocky country were outlined for the survey.

The tracking team: Tim, Paul and John
 










The tracking team - John, Tim (Timotheus Andreas, an assistant on the Reserve) and Paul then spent several days systematically walking back and forth either along N-S or E-W paths to sample these zones. If John identified the pangolin markings as very recently-made, then a localized search in a spiral fashion around the site for other new feeding sites was made.

Markings two days old, showing 2 small paw prints and the tail trace
















Whenever a pangolin feeding site could be definitely identified from the marks made by other animals, its recency was assessed and its position logged using a Garmin GPS. Fresh marking were also photographed. More than 200 such sites were logged in total, walking about 65km for the survey. Some pangolin activity estimates to compare the zones were calculated in terms of the average number of feeding sites found per km sampled within the zone.

 









Pangolins often sleep during the day in the deep burrows or warrens made by big aardvark 'excavators'. So these dens were also investigated for signs of recent pangolin residency.


One aardvark hole seemed to have pangolin tracks less than a day old in its entrance. After photographs, the entry ground was cleaned and smoothed out, so that any new tracks would be clearly revealed. John and Paul returned to this spot at 4pm hoping to capture the pangolin when it emerged at night to sniff out termites and ants. They kept a silent vigil nearby through the end of the day until about 11pm, using a infrared night sight to monitor the hole, but unfortunately without success. No fresh tracks were found a day later at the entrance, so the pangolin responsible must have already left, or mischievously found another exit burrow from the aardvark warren.

Aardvark hole with recent markings
Starting the vigil











Despite evidence of much pangolin activity and even several feeding sites discovered in two of the sandy zones which were only 1 or 2 days old, sadly the pangolins remained elusive- to the disappointment especially of John, an expert bush tracker. As a pangolin probably browses over a few km in a day (night) and their territory is likely to be several sqr. km, locating one is certainly like finding a needle in a haystack! If disturbed above ground, they would keep very still in the undergrowth and be difficult to spot. Perhaps there were times when a pangolin was only tens of metres away, watching the survey team! Pangolins are notoriously difficult to find, even bush-hardened rangers go years without seeing one. Most human encounters seem to be by chance when they have been spotted crossing a path or road.

Eventually, time ran out to find a pangolin during this ~3 week preparatory field trip. Paul took John back home, parting as good friends, both hoping that his skills can help our project again. The round trip to Tsumkwe was made this time in a single very long day of driving. Arriving at Tsumkwe to find that the pumps were empty, no petrol having been delivered to the fuelling station there since the last visit, it was very fortunate that the Nyae Nyae Conservancy Office kindly spared some for the return leg! Mundulea was reached just in time to drive the last rough kms up to the Mundulea farmhouse, spotting a herd of wildebeast at sunset.

 

Results of Pangolin Feeding Site Survey

An overview GPS map using Garmin's MapSource software of all the pangolin feeding sites identified in the four sandy zones surveyed in Mundulea is shown below. The zones are outlined in grey, with some other landmarks added for reference. Each feeding site (or local cluster of several) is shown as a green star along the walked tracks. A few prominent aardvark warrens of the many encountered are marked with red triangles. The sites ranged from one day old to a few months old (i.e. after the previous rains). As expected statistically, most of the sites found were old, i.e. made more than a week previously. More detailed maps can be made, highlighting the recency information that was recorded.

To get an idea of the relative pangolin activity in the different zones, averages of the number of feeding sites found per km walked were calculated. (Of course the longer the distance walked, the more likely statistically it is that feeding sites will be found). As pangolins tend to be solitary, we can speculate that the activity is due to about 3-4 individuals.

The maps help us start to understand the preferred pangolin areas and begin a correlation with geological and botanical information. In the long term we would like to relate pangolin activity in such semi-arid savannahs with that of its prey species, working with expert entomologists. Of course, the availability, activity and depth at which prey are to be found depend both on the Namibian season, the amount of recent rain and the particular species of ant and termites. Pangolins only forage the surface and do not dig deep for food. During the cold Namibian winter (~June-July), Cape Pangolins hibernate underground in burrows.

Discovering Our First Pangolin, Oct 30th 2010

As luck would have it, on October 30th just 3 weeks after Paul returned to the UK from his field trip, Tim was out walking when he spotted a large pangolin looking at him! Despite cutting his fingers on its sharp scales, he managed to capture it. The large pangolin was a male and in very good condition, weighing 8.6kg.















Unfortunately there were some initial problems with the long-battery life RF tags, so we couldn't immediately tag and re-release the pangolin. We tried to keep the pangolin for a while inside a workshop on the Reserve, even taking it for 'walks' to feed in ant and termite country. However, as mentioned on Wikipedia, these animals are well known 'escape artists' - it soon managed to tunnel through the thin concrete floor into the basement - see the photos below! Anyone considering keeping a pangolin in captivity should realize there are big problems in their enclosure and husbandry.









Because of the great difficulties of adequately feeding a pangolin in captivity, the pangolin had to be released before new corrected tags arrived by courier in Namibia to attach to the animal. We want to get some experience in building ant traps for their preferred prey, as has been successfully done for Asian pangolins, before trying again.

 
(Photos in this blog post are courtesy of  Graham Higgs







So Tim's pangolin trundled off into the sunset in good condition. We hope to encounter it again one day in Mundulea: it should be recognizable by the wear patterns of its scales.