In our last blog post (Discoveries From Two Years With Kenya’s Warthogs) we provided an overview of the major findings of our Quest for Kenya’s Desert Warthog. Of course, we collected a considerable amount of information on other species as well.
Here we present some of our findings about the primates of northwest Kenya.
Of the 25 genera and 93 species of primate in Africa, 12 genera, 19 species, and 25 subspecies occur in Kenya. Northwest Kenya is an under-explored region. As the primates of northwest Kenya have not been studied, we assessed which kinds are present, as well as their distributions, abundance, threats, and conservation status.
Mau Forest Guereza Ranging Wider and Higher
A population of Mau Forest guereza (Colobus guereza matschiei) was found in the central Cherangani Hills. This extends the geographical range of this subspecies 50 km to the northeast (from Mt. Elgon). It is likely that the range of Mau Forest guereza extents to the north end of the Cherangani Hills. Previously, the highest altitude reported for this subspecies was 2,900 m above sea level. Two groups of Mau Forest guereza were, however, encountered at 3,009 m above sea level. We found that most of the natural forest of the Cherangani Hills had been cleared, and that much of what remained was degraded and fragmented.
Wider Range for the Eastern Patas Monkey
A group of eastern patas monkeys (Erythrocebus patas pyrrhonotus) was encountered in the south end of the Karasuk Hills, close to the Uganda border, central west Kenya. Interviews with local people indicate the presence of many groups of eastern patas monkeys in this region. This locality record confirms earlier reports of eastern patas monkeys along the Kenya-Uganda border and falls within a distribution gap of about 130 km (between western Turkana County and western West Pokot County). The current range of the eastern patas monkey in Kenya is estimated at 52,520 km² (in 2008 we estimated this to be 48,200 km²). This is about 56 percent of the historic range.
A Rainbow of Savanna Monkeys
Instead of noticing separate ranges, we observed a gradation of physical traits from one species to another of savanna monkeys (Chlorocebus spp.) across central west and northwest Kenya. Individuals in a group of supposed vervet monkeys (Chlorocebus ‘pygerythrus’) at Lodwar had some of the coat color characters of the grivet monkey (Chlorocebus aethiops). The known range of the grivet monkey includes southeast South Sudan … but not Kenya or Uganda. The one adult male savanna monkey observed at Karasuk Hills showed color characters of the tantalus monkey (Chlorocebus tantalus).
Altitude and Rainfall Records for the Olive Baboon
During this survey we encountered 80 groups of olive baboons (Papio anubis). These groups were at altitudes ranging from 369 m asl (Kalacha, an oasis town in the northern Chalbi Desert) to 2,320 m asl (Lolldaiga Hills, Laikipia County). Previously, the lowest altitude record for olive baboons in East Africa was at 540 m above sea level (Meru National Park, central Kenya).
Olive baboons typically drink daily. In north Kenya, olive baboons occupy areas with a mean annual rainfall as low as about 200 mm (Marsabit County, east of Lake Turkana). This is a lower rainfall than previously reported for this species (300 mm, west Eritrea). The absence of drinking water for several months at a time in these areas indicates that olive baboons are able to survive without drinking for extended periods. This has not been previously reported (see our blog: Secret to Olive Baboon Survival in a Barren Desert).
Two New Populations of the Somali Lesser Galago
Two new populations of Somali lesser galago (Galago gallarum) were located; one in an oasis on the eastern edge of the Chalbi Desert (New Population of Bushbabies Discovered in Northern Kenya) and one on the southern foothills of Mt. Forole, central north Kenya. These sites extend the known geographical range for the Somali lesser galago in north Kenya about 100 km west into the Chalbi Desert and about 80 km west along the Kenya-Ethiopia border, respectively.
Two New Localities for Senegal Lesser Galago
Two new localities for the Senegal lesser galago (Galago senegalensis senegalensis) were found; one in the Charangani Hills and one in Saiwa Swamp National Park, central west Kenya.
Additional photographs obtained during this project can be viewed at: www.wildsolutions.nl. These include photographs of primates, warthogs, hyraxes, antelopes and landscapes.
To obtain the final report for this project, go to www.wildsolutions.nl.