Understanding Burseraceae: Trees of Eastern Africa

Understanding Burseraceae: Trees of Eastern Africa

Commiphora bushland in eastern Hiraan Region, Somalia (Photo: Peter Kuchar)

THE BURSERACEAE

Those of you who downloaded digital copies of The Burseraceae by Kuchar and Gillett on storiesofeastafrica.com will welcome the updated version now available at Kuchar & Gillett – The Burseraceae (Dec 2025).

For those unfamiliar with the term, Burseraceae is a family of shrubs and small trees. In Somalia, it comprises two genera, Boswellia and Commiphora, the latter probably the most diverse, abundant, economically important, yet worst understood and documented genus of woody plants in the Horn of Africa. This report not only explains why but also includes information (Somali names, uses etc.) about Burseraceae species in (pre-1989) Central Somalia, not to mention a very useful vegetative key for identifying them. 

A commiphora tree showing the species’s iconic contorted appearance.

Author: JMK, C.C.C-Share Alike 4.0 International license

RANGELAND DOCUMENTS RELEVANT TO LARGE AREAS OF SOMALIA.

RANGELAND DOCUMENTS RELEVANT TO LARGE AREAS OF SOMALIA.

Speke’s gazelle is a very rare small antelope that is similar in appearance to the Thomson’s gazelle encountered by tourists on the Serengeti Plains in Tanzania. It inhabits a 20-40 km wide grassy plain along much of Somalia’s coast. In the mid 80’s it also occurred in the northern Ogaden of eastern Ethiopia. cc-by-sa-2.0. FlickreviewR 2

This announces the availability of another batch of free downloads of hard-to-find documents on the rangelands of Somalia: Twenty-six reports on subjects ranging from the Trees of Somalia, a sand movement inventory, and the traditional Deegan ecological classification, to the Yeheb nut and Spekes gazelle. Publication dates range from 1907-2013. Several reports, originally published between 1954 and 1976, are translations of articles in Italian journals (1954-1976).

FREE DOWNLOADS OF HARD-TO-GET DOCUMENTS ON THE RANGELANDS OF SOUTHERN SOMALIA

FREE DOWNLOADS OF HARD-TO-GET DOCUMENTS ON THE RANGELANDS OF SOUTHERN SOMALIA

Featured image: Densities of goats November / December 1983

This announces the availability of free downloads of hard-to-find documents on the rangelands of Southern Somalia, an area larger than Great Britain. These include 2 published papers, 15 reports and 87 maps. Twenty-six of the maps compare wet and dry season densities of dynamic resources, including livestock, wildlife, cropping and seasonal habitation. Publication dates range from 1980 to 1992. https://storiesofeastafrica.com/the-southern-rangelands-of-somalia-2/

Free Downloads of Documents on Central Somalia Rangelands

Free Downloads of Documents on Central Somalia Rangelands

Free Downloads on Central Somalia Rangelands

Free Downloads on Central Somalia Rangelands

Featured image: A village in Central Somalia

RANGELANDS OF CENTRAL SOMALIA

RANGELANDS OF CENTRAL SOMALIA

REPORTS BY RESOURCE MANAGEMENT AND RESEARCH, LONDON.

This announces the availability of free downloads for the first set of hard-to-obtain reports on the rangelands of Central Somalia. https://storiesofeastafrica.com/reports-on-the-rangelands-of-central-somalia/

This post includes surveys and maps carried out in 1979 by Resource Management and Research (RMR), London. Reports by other agencies will follow in future posts.

DIGITAL COPIES OF PUBLICATIONS ON THE RANGELANDS OF SOMALIA

DIGITAL COPIES OF  PUBLICATIONS ON THE RANGELANDS OF SOMALIA

(Featured image: Dr. Tom Thurow and Somalia National University students collecting rangeland composition data on the coastal plains of Central Somalia.)

Because Its rangelands are Somalia’s primary natural resource, a considerable amount of research has been carried out over the last several decades to determine their productive potential and how they may best be managed. Unfortunately, much of the resulting information was not widely published and is, therefore, now difficult to obtain. This post is the first of several to at least partially remedy this situation by making available digital copies of relevant publications and reports for free downloads

Introducing Digital Copies of Publications on the Rangelands of Tanzania

Introducing Digital Copies of Publications on the Rangelands of Tanzania

Featured image: Eleusine jaegeri, a large tussock grass, dominates the highland grasslands of the Ngorongoro Conservation Area. It is unpalatable except when young. Consequently, grazing pressure is confined to an underlying mat of palatable grasses (Andropogon, Cynodon, Digitaria, Sporobolus) which is kept low by constant usage.

Several months ago I made digital copies of the Range Management Handbook of Kenya available online. The response was so positive that I’ve decided to continue with other difficult-to-obtain publications on eastern Africa’s rangelands. Today I’m happy to announce the online availability of several digitized publications on the rangelands of Tanzania!

During the mid 1960’s and 70’s I was involved in, among other things, surveys of vegetation in Tanzania. Whenever possible, I also obtained copies of other surveys and studies, six of which I have digitized. Published between 1967 and 1978, they are now out of print and hard to obtain. Nonetheless, they may still have some value, be that for planning, instructional, research, or historical purposes. 

If you find these useful, please do let me know!

Also, if you have paper copies of additional publications on the rangelands of Tanzania and would like me to digitize them and make them available, please send me an email.

UPDATED RANGE MANAGEMENT HANDBOOK OF KENYA

UPDATED RANGE MANAGEMENT HANDBOOK OF KENYA

Featured image: Production risk due to lack of rainfall in Marsabit District

Now available for free downloads: digitized copies of the 22 reports (3 volumes) comprising the Range Management Handbook of Kenya.

For information on rangeland resources, climatology, livestock diseases, constraints facing range development, and much more, go to the sidebar and click on Range Management Handbook of Kenya. Alternatively, click on storiesofeastafrica.com/range-management-handbook-of-kenya/

Some examples of newly available reports / maps appear below.

District-wide maps provide inventories of natural resources and their ecological status

Environmental degradation is ongoing in the rangelands of East Africa. This guide shows how to identify and monitor soil erosion in arid and semi-arid lands.

Camels, which typify arid rangelands, have, in recent years, also become a presence in semi-arid rangelands. See this report for tips on how to manage them.

MAASAI PASTORALISTS OF NGORONGORO: AS THEY ARE NOW

MAASAI PASTORALISTS OF NGORONGORO: AS THEY ARE NOW

In the mid-1960’s, the pastoral Maasai of Ngorongoro, proud of their reputation for being fierce warriors, and possessing an abundance of cattle, were content with their way of life. Thus, they were conservative and resistant to change, an attitude that frustrated government officials, both pre-and post-independence, and gave the Maasai a reputation for being backward. (Adapted from the previous blogpost, The Maasai of Ngorongoro: 1960’s.)

Over half a century later their situation has changed–drastically.

For instance, due to better health care, and the immigration into the Ngorongoro Conservation Area (NCA) of other pastoralists (especially during droughts), the human population is now twelve-fold greater.

In contrast, several factors have constrained growth of the livestock population: (a) Valuable grazing lands have been lost to other uses, primarily wildlife conservation and tourism, (b) Livestock carrying capacity has declined due to overgrazing, a ban on setting grass fires, and recurring droughts, (c) Livestock deaths have increased due to diseases and droughts.

DETAILS

Valuable grazing land was lost when the Ngorongoro Conservation Area Authority (NCAA), concerned that the Maasai and their livestock were hindering wildlife conservation, removed them from Ngorongoro, Olmoti, and Empakaai craters in the 1970’s. (Ngorongoro Crater was an especially hard loss.)

Ngorongoro Crater is the largest in the Crater Highlands. Empakaai Crater contains a small, but lovely lake. Graphic by David Bygott and Jeanette Hanby.

Ngorongoro Crater, 97 sq. miles (252 sq. km) of productive rangeland. (View from my house on the crater rim in 1964.)

Also, expanding numbers of wildebeests calving in the wet season on the eastern Serengeti Plains, and the associated risk of cattle catching malignant catarrh fever (MCF), forced herders to keep their livestock in the highlands for extended periods. The reduced ability of the Maasai to use this wet season grazing area caused an estimated 35% reduction in cattle numbers.

Wildebeest calves on the eastern Serengeti Plains, which lie entirely within the NCA. From 1961 to 1977, the Serengeti wildebeest population grew from 250,000 to its present level of approximately 1,277,000. This caused the area used for calving to significantly expand. Photo by Dirk Kreulen.

Afterbirth of a wildebeest calf. If cattle graze grass that has been touched by it they are apt to contract (and die from) malignant catarrh fever (MCF). Photo by Dirk Kreulen.

Forage quality and production dropped (at least for cattle) in parts of the Serengeti Plains because of declining grass and increasing shrub cover associated with a ban on setting grass fires imposed by the NCAA. (Pastoralists typically burn grasslands to kill ticks, remove dry grass, suppress woody plants, and induce greening of the vegetation.) Increasing abundance of unpalatable grass species in the highlands probably reflects overgrazing.

Grass fire on the floor of Ngorongoro Crater. A decrease in fires following removal of Maasai and their livestock from the crater in the 1970’s resulted in taller grasses and lower grassland species diversity. (Also, as I can personally attest from having to pick them off my pants in 2004, more ticks.)

Livestock deaths, especially of cattle, increased when herders, unable to use wet season pastures on the eastern Serengeti Plains, were forced to keep their animals for extended periods on traditional dry season pastures in the highlands. This increased the exposure of cattle to ticks, vectors for East Coast fever (ECF). Major die-offs occurred. A good example is provided by Andrew Clark, who in 1967, described the results of a virulent outbreak of ECF in Loliondo, north of the NCA: “Hundreds of cattle died in a few weeks. The whole area stunk of rotting carcasses. Hyenas, bellies pendulous from gorging, could barely walk. Vultures were so stuffed they could hardly get off the ground.”

Ticks, carriers of East Coast fever (ECF). They become abundant on rangelands which are seldom burned and/or are used for extended periods by livestock. Photo by Dr. Alexey Yakovlev. CC Attribution-SA 2.0 G.L.

Veterinary staff with bones of Maasai cattle killed by East Coast fever in Loliondo, Photo by Andrew Clark.

As a result, Maasai pastoralists were forced to reduce the proportion of cattle in their herds and increase that of goats. This is because goats are less susceptible to disease than cattle.

A mixed herd of goats and sheep. Goats also reproduce more quickly, produce milk throughout the year, utilize a variety of habitats (Cattle are restricted to grasslands), are drought-resistant, and easy to sell and slaughter. Thus, they are the fallback livestock for impoverished pastoralists.

Finally, droughts are becoming more frequent, and lengthy. Consequently, the grasses that provide forage for cattle are less able to recover their vigor between droughts, making them less productive. Thus, they support fewer animals, which tend to be weaker, in poorer condition, and more apt to die during the next drought. The drought ending in 2009, one of the most serious in recent memory, killed 35-40% of all cattle in Ngorongoro District, which includes the Ngorongoro Conservation Area (NCA) and, to the north, Loliondo.

THE CONSEQUENCES OF CHANGE

The result of all this is that, even though animal numbers have increased, the livestock population, especially of cattle, has not grown in accordance with the human population. Livestock biomass per pastoralist, well above subsistence level in 1966, is now below subsistence level.

This has caused the Ngorongoro Maasai, with too few livestock to support themselves, to become so impoverished that they must find other ways to supplement their livestock-based subsistence economy. Presently, they cultivate. Unfortunately, most are still too poorly educated to be employed in the region’s burgeoning wildlife-viewing tourist industry (six tourist lodges in the NCA alone). Those migrating to cities generally only find work as low-paid security guards.

This 2004 scene of Maasai bomas shows two examples of change since the 1960s: (a) cultivation , and (b) huts unprotected by fences (Predators may no longer be a problem, or the Maasai now know how unhealthy it is to live at close quarters with livestock inside the stockades).

Maasai security guards in Zanzibar. Photo by Jack Meyers.

Nonetheless, despite there being too few livestock to adequately support resident pastoralists, the Ngorongoro Conservation Area Authority (NCAA) is still concerned that there are too many for the land to support. It is especially worried about the ecological impact of overgrazing (as well as that of settlements and cultivation) on wildlife-based tourism, a major source of foreign currency (in 2017, 650,000 tourists visited the Ngorongoro Conservation Area, generating about 65 million $ U.S.) https://africasacountry.com/2022/04/people-live-here).

And the government is worried, too: The National assembly recently debated whether the Maasai even have a right, guaranteed in laws as far back as 1959, to live in the NCA. Also, recent reports in the media (denied by the government), state that it is considering relocating 80,000 Ngorongoro Maasai–much, if not most of the total population–outside the NCA. Whether or not this eventually happens, the NCAA/Tanzania government are “encouraging” impoverished herders to go elsewhere. Furthermore, a few hundred Maasai recently have, moving 210 miles (340 km) to Handeni in eastern Tanzania https://www.kbc.co.ke/hundreds-of-masai-ready-to-leave-conservation-area/.

Is this the future of Ngorongoro’s Maasai?

To best secure their future, the Maasai of Ngorongoro must become better educated. Photo by Christopher Michel. CC Attribution 2.0 GL.

ADDITIONAL REFERENCES

Amiyo, T.A. 2006. Ngorongoro Crater rangelands: condition, management, and monitoring. MS thesis, School of Biological and Conservation Sciences, University of Kwazulu-Natal, Pietermaritzburg.

Borges, J. et al. 2022. Landsat time series reveal forest loss and woody encroachment in the Ngorongoro Conservation Area, Tanzania. Remote Sensing in Ecology and Conservation. Open Access https://doi.org/10.1002/rse2.277.

Galvin.. et al. 2015. Transitions in the Ngorongoro Conservation Area: The story of land use, human well-being, and conservation. Pages 483-512 in Serengeti IV: Sustaining biodiversity in a coupled human-natural ecosystem. The University of Chicago Press.

Homewood, K.M. & W.A. Rodgers. 1991. Maasailand ecology: Pastoralist development and wildlife conservation in Ngorongoro, Tanzania. Cambridge University Press.

Ngorongoro Conservation Area Authority. 1966. General Management Plan. Tanzania Ministry of Natural Resources and Tourism.