Category Archives: Samburu Survey

Thank you Brenton for supporting a Primate Guardian

On behalf of the management of Samburu Primates Research and Conservation Project, I would like to thank Mr Brenton H for giving a donation of $ 690 to go towards supporting the wages of a Primate Guardian for six months. Lembasha J., a local trained in community development and with great interest in the conservation of Mathews range forest biodiversity has been recruited.

The role of the PG is critical in the ongoing monitoring of rare and endangered primates in the forest, in addition to raising awareness on the threats affecting these primates’  in order to reduce anthropogenic pressure on their habitat. The PG is working with the other stakeholders in the conservation sector to ensure that the project’s activities complement other ongoing conservation efforts in the Mathews range ecosystem.

‘Asante Sana’ Mr Brenton
Iregi Mwenja
Project Leader

Swara: Endangered colobus facing extinction

Click on the on the image below to read the Swara magazine article on the Endangered Mt. Uarges guereza. The article highlights the finding of an extensive survey of the Samburu forests that was concluded last year. The Survey was generously funded by Rufford Grants Small Foundation.


Iregi Mwenja

Principal Investigator

Samburu Primates Research and Conservation Project

Poaching drives an Endangered monkey to the verge of extinction

The Mt Uarges guereza, Colobus guereza ssp. percivali is one of the eight subspecies of the Colobus guereza species. It is endemic to the forests of Samburu and is the only one of the eight listed as Endangered in the IUCN Red List.


According to the findings of a survey I headed in Mt Nyiro forest, Ndoto forest, Kirisia Hills and Mathews range forests (between April 2007 and December 2008), the subspecies has been heavily poached for its skin by the local community who wear it during traditional ceremonies like circumcision. The skin is worn by ‘Morans’ on the lower part of the shin and round the heads during such ceremonies.


samburu-wearing-colobus-skin.jpg A man demonstrating how the skin is worn


Information we gathered over this period indicate that the ‘Lkoroi’ as it is locally known, once thrived on the eastern side of Mt Nyiro– Tum and Ewaso Rangai (lorian). Interviews with old men in Mt Nyiro and a retired colonial District Forest Officer who served in the area 50 years ago revealed that it is possible that there were guereza colobus in the Mt Nyiro forest up to the 1950s. All of them attributed the disappearance to poaching for the skin and habitat degradation due to encroachment during drought and periods of tribal conflict between the Samburu and the Turkana. The Turkana who use the skin as a head gear are said to have obtained it from Mt Nyiro as well.


In Kirisia Hills from the outskirts of Maralal to Baawa, Poro to Ang’ata Nanyuki, most of the adults interviewed admitted to having seen the subspecies in the forest in the last decade and blamed the dramatic decline of the subspecies population in this habitat on the proliferation of small arms which spiraled in the 1980s. Thea arrival of these semi automatic weapons made hunting the agile arboreal monkey extremely easy as oppossed to the traditional snare hunting methods. At Ol Dionyo Naju, we got reliable reports that the last remaining colobus in the area was killed in 2006 ostensibly for the skin. My fear is that Kirisia hills will soon go the Mt Nyiro way as it was clear that the monkey have been wiped out in most of its range within the Leroghi forest reserve.


Though the skin is passed over from father to son over generations, interviews with Morans around Maralal indicated that the skins was scarce and they were now turning to Mathews range forest where the subspecies is readily available for fresh supplies. Here the monkey is found in hundreds particularly on the central and southern parts of the forest reserve.  The monkey is an easy target as it is not accustomed to poaching like in Kirisia Hills where they have been known to actively avoid close human contact.


It is imperative that action be taken to halt the killings of the few remaining member of this subspecies before we lose the last stable population in Mathews range forest reserve.  This can be done through aggressive awareness rising coupled with improved law enforcement on the short term to halt further declines in the population of this Endangered primate.


mt-uargess-guereza.jpg Photo of the rare Mt Uarges guereza taken along river Wamba on Mt Uarges. Photo: Mwenja


Colobus guereza information


The species Colobus guereza is widespread across Africa and ranges from the Donga River region of Nigeria and the Yabassi District of Cameroon, eastwards across the Oubangui River from the Central African Republic to the northern Democratic Republic of the Congo, and then discontinuously eastwards to southern Sudan, Uganda, the Kenyan and Ethiopian highlands, and Mount Kilimanjaro, Mount Meru and the Kahé District of Tanzania.


The eight sub-species are;


1.      Colobus guereza ssp. caudatus
2.      Colobus guereza ssp. dodingae
3.      Colobus guereza ssp. gallarum
4.      Colobus guereza ssp. guereza
5.      Colobus guereza ssp. kikuyuensis
6.      Colobus guereza ssp. matschiei
7.      Colobus guereza ssp. occidentalis
8.      Colobus guereza ssp. percivali


For more details on the survey, please contact me on the iregim[at]


Iregi Mwenja

Finally, the survey findings are out!

After twenty months of on-the-ground assessments of six rare primate species in Samburu, the verdict is out! There was some good news and some bad news as well. Below is a brief summary;

The aim of this survey was to validate presence and map the distribution of six rare primates species in Samburu. The species are; the de Brazza’s, the Sykes and the Patas monkeys, the Somali and the Senegal lesser galagos and the Endangered Mt Uarges guereza. Very little was known on the presence and status of the six species in the district prior to this study. Below is a brief summary of the findings;

De Brazza’s monkey
From the beginning of the survey in April 2007, six more groups of de Brazza’s monkey were recorded on the northern Mathews range, an addition to the 24 groups recorded in the year 2006 during the first survey of this newly discovered population. Between May 2008 and December 2008, two new groups were sighted in Sererit – southern Ndoto.

Patas monkey
Apart from the one stray (from Laikipia) Patas monkey reported by Dr Iain Douglas-Hamilton of Save the Elephants which he saw on the western parts of Samburu National Reserve, no other Patas monkeys were seen in the district. The conclusion is that there are no Patas monkey is Samburu.

Sykes’ monkey
Reports about a small population Sykes’ monkey on the northern fringes of Leroghi forest – at Ang’ata Nanyuki were found to be unreliable as no monkey was seen in 8 months of intensive ground search in that area. Based on this information, our conclusion is that here are no Sykes monkeys in Leroghi forest or any other part of Samburu. Mt Kenya remains as the northern limit of the species range.

Mt Uarges Guereza
The Endangered Mt Uarges guereza was found in substantial numbers distributed over central and southern parts of Mathews range forest and southern Parts of Ndoto forest. The population in the neighboring Kirisia Hills was last seen in 2006. The few remaining are believed to have taken refuge in the dense inaccessible part of the forest (Saanata) following two decades of persistent poaching by local people who highly value its skin.

Lesser Galagos
The Senegal lesser galago was found to be widespread in the district. Eight live specimens were collected and released at South Horr (Mt Nyiro) and Mathew range after taking body measurements. However, the Somali lesser galago was not seen though there were reliable reports of sightings in the southern drier of the district.

Email me to a copy of the full report.

Iregi Mwenja

Finally, the good news on rare monkeys of Samburu

For the last one and half years,  we have carried out an extensive survey of six rare primates species in the plains and forest of Samburu; from Mt. Nyiro in the north to Uaso Ng’iro river in the south. Whereas we found some like the senegal lesser galago to be plenty, sykes monkey in Leroghi remained elusive and only one Patas monkey was reported on the south in the Samburu national Reserve. There was more good news for de brazza’s monkey as more groups were discovered in Ndoto. For more details, see the summary below or email me to get a copy of the full report.

I am grateful to Milgis trust’s Moses Lesaloiya and Helen Dufrense and their highly skilled scouts for their effort in making this survey a success.


This primates’ survey was carried out in Samburu district of northern Kenya with semi-arid lowland and forested highland mountains. The aim was to study the distribution of the following rare primates’ species; the de Brazza’s, the Sykes and the Patas monkeys, the Somali and the Senegal lesser galagos and the Mt Uarges guereza. The six have received marginal attention and their status in the area is poorly known.

De Brazza’s monkey

During the survey that started in April 2007, six more groups of de Brazza’s monkey were recorded on the northern Mathews range, an addition to the 24 groups recorded in the year 2006 pioneering survey of de Brazza’s monkey. Additionally, Milgis Trust game scouts also reported new groups in southern parts of Ndoto forest.

Patas monkey

In the district, only one Patas monkey was officially reported. Dr Iain Douglas-Hamilton of Save the Elephants reported seeing one Patas monkey on the western parts of Samburu National Reserve. Given the mobile of nature male Patas and the proximity of the reserve to the Laikipia population, this sighting could not be construed to mean that there is a new resident group in the district yet.

Sykes’ monkey

A very small population Sykes’ monkey is believed to be present on the northern fringes of Leroghi forest although tangible evidence has been had to come by. However, effort to get hold of such evidence his still ongoing.

Mt Uarges Guereza

The Endangered Mt Uarges guereza is found in substantial number distributed over central and southern parts of Mathews range forest. The population in the neighboring Kirisia hills and Leroghi forest was last seen by Forest Guards in 2006 and is now believed to have sought refuge in the dense inaccessible part of the forest following two decades of persistent poaching by local people who highly value its skin.

Lesser Galagos

The Senegal lesser galago was found to be widespread in the district. Eight live specimens were collected at South Horr and Mathew range. However, the Somali lesser galago was not seen though there were reliable reports that it is common particularly on the southern drier parts of the district.

senegal-lesser-galago.pngSenegal lesser Galago collected at Ngare Narok on Mathew range

Iregi Mwenja

Presenting my team

The Samburu primates study that I lead is made up of research assistants, guides, scouts and secuirity escorts who are mostly drawn from the local Samburu community. I am glad to share with you photos of some of the peope that have made the fieldwork part of this study a success.

Mwenja's team 3.JPG The Team at Ngare Narok in september 2007 where we were making preliminary observations of the ecology of the newly discovered population of de Brazza’s monkey in Mathews range.

Mwenja's team.JPGThe Ang’ata Nanyuki team in Leroghi where our search for sykes monkey were fruitless in June 2007.

Mwenja's team 1.JPG The Uaso Ngi’ro rivers near Lodung’okwe. The team which I led was searching for sykes monkeys believed to have been in this area in the 1980s

Mwenja's team 4.JPG The team at Lagat valley in Baragoi searching for Patas monkey

086.JPG Another team at Angata Nayuki in Leroghi that was looking for Patas and sykes monkeys

Mwenja's team 2.JPGA guide and an escort in last year’s de Brazza’s monkey survey in Mathews range.

The list is not exshaustive as not all of them are currently available in my photo library. As you read my posts, please remember that this people played a crucial role in the study and they deserve credit for their contribution. I am personally very grateful to my team for serving with deligence and dedications despite the numerous difficulties and hardships, especailly lack of adequate resources during feildwork.

Iregi Mwenja

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Climbing Mt Nyiro

Climbing Mt Nyiro was the most physically challenging moment of my primates survey fieldwork in Samburu this year. The photos say it all…

DSC00131.JPGClimbing from South Horr

DSC00132.JPGMy local Guide, Ljejian

DSC00145.JPGTaking a break

DSC00147.JPGAnother Break

It took us ten hours to get to Kurante where we picthed our tents before heading to Kosi Kosi (which is 2600 m above sea level) the next morning.

Finally the view


DSC00142.JPGSouth Horr trading center and the Ndonyo Mara on the background

Iregi Mwenja

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Delayed field trip

I have been forced to postpone my last field trip of the year following continued rains in Mathews range whose river drains to the Milgis river on the western side. I have been planning to survey the Ndoto by going round the mountain using the Milgis lagga (dry River bed) as it is the only way to cross over from the west. Until the River bed is dry, most parts on the south are inaccessible. If I go now, I will only be able to access the mountain from Ilaut side via Baragoi-South Horr road and leave out the crucial southern parts. The General elections are also due in two weeks and it would not be advisable to conduct the study during the last days of campaigns and voting day. The is also the festive season and christmas is around the corner and it will be difficult to convince people to join me, like it happened last years during my last fields trip of the Mathews range de Brazza’s survey.

Ndoto, northern side's view from Mt Nyiro

Ndoto mountains, a view of the northern side’s from the top of Mt Nyiro, 30 km away

iregi's photos Suiyan2005-04-23 WPZoo 081adj (Custom).jpg

Seiya river and a patas monkey

I have been able to get this regular updates courtesy to my partner on the ground – Milgis Trust. The Manager, Moses Lesoloiya have also been assisting with leads into unconfirmed reports of patas sightings at Suiyan and trip logistics, including transport and scouts. We have agreed to make it early January.

Mwenja at Lagat lagga

Mwenja searching for patas monkey at Lagat river, a tributary of the Seiya river four months ago.

iregi's suiyan plains near baragoi

Open grassland near suiyan with a view of Leroghi/Kirisia Hills on the background

iregi's Baragoi accacia bushland

Acacia bushland which offer ideal conditions for patas monkey habitation

Iregi Mwenja

Project Leader

Samburu Primates

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More skulls

Thanks Louise for your assistance with the skull identification. I take photos of everything I come across and sometimes they happen to be species outside my speciality. But how did this buffalo skull at Mathews range end up with a new body! I just liked the image.


There is a fossilized remains of an elephant skull at Marti which residents claim has turned into a rock. Does that interest you? I could get speceimens next month, for free!

Iregi Mwenja

A small but costly mistake in the field

As I promised in the last post, I have posted this link to a video that showing how the Samburu make fire for dried sticks. This is how the Samburu people used to make fire before modern fire lighters were introduced. We had to rely on this method after we forget a fire lighter in our car (which was parked 15 km away at Marti) during a Patas’ monkey survey along the Lagat valley

It was late in the evening and we couldn’t find the species required to make fire in the valley. We spent the night without food after the 15km walk to Lagat Valley. The next morning, had to call-off the survey and return to Marti, another 7 hours walk in a temperatures above 30 degrees Celsius. On the photo in the last post, we had done about 10 km and had run out of the precious water. That morning, we threw away our raw foodstuff – potatoes, rice and beans to cut on our luggage and save our dwindling energy to walk to the car at Marti.


So my sadness had nothing to do with insecurity! But I learnt a valuable lesson. To pack one item at a time! Next month I will be back and you guess what will be the first item in my luggage!

Back at Marti, I bought a chicken from the locals which was prepared for us as we had animated discussions with the Morans who couldn’t understand why these people have to leave their comfort in Nairobi and subject themselves to the hardship in such remote and insecure places. What they will never understand is that this is adventure to me, not hardships. It’s fun. It’s want I want to do for my country, to help save our planet!

Iregi Mwenja