Analysis of Nexus Between Climate Variability, Herd Mobility and Livestock Disease Incidences in the Rangelands of Northern Kenya

Abstract

Arid and semi-arid lands occupy at least one-third of the planet’s land area, while in Africa, they comprise about two-thirds of the continent. These ecosystems are subject to diverse drivers including rainfall variability, fire, and grazing and browsing that end up creating a dynamic and patchy rangeland landscape that is inherently unpredictable in space and time. Pastoral herd mobility is a key coping strategy in the arid and semi-arid rangelands where grazing and water resources are highly variable in space and time. The spatial and temporal climate variability dictate herd mobility, and therefore understanding this interrelationship is key to sustainable management of rangelands and livestock production, especially in the face of the changing climate. The constraints that come with herd mobility includes ineffective veterinary services delivery system, inadequate infrastructure and inefficient information dissemination mechanism. This study was undertaken in Samburu County in Kenya, an area characterized by varying climatic conditions, land uses and agro-ecological zones to analyze local perceptions on climate variability and pastoralists coping strategies, determine the interrelationship between rainfall and temperature variability and the mobility of herds and determining the effects of seasonality on livestock disease incidences. To achieve the research objectives, Household surveys, Key informant interviews, 20-years data for temperature, rainfall, normalized difference vegetation index (NDVI) and geo-referenced data (GIS) together with field data obtained through household interviews and community participatory mapping were utilized. Drought was perceived to be more severe while rains to have been decreasing. A statistically significant association was noted on the perception on the trend of rainfall and the study sub-locations (χ2= 19.438, df= 1, p= 0.000), temperature (χ2= 15.215, df= 1, p= 0.000), floods (χ2= 18.301, df= 1, p= 0.000) and drought (χ2= 22.016, df= 1, p= 0.000). Pasture availability was said to be the most important factor when it comes to decision-making on where pastoralists will move their animals as mentioned by 100% of the respondents. This was followed by water availability (97.4%), conflicts (79.4%), type of livestock kept (79.1%) and emergence of livestock diseases (72.8%). Pastoralists coping strategies included migration, eating wild fruits, reducing the herd size as well as herd splitting. Wet-season and dry-season grazing areas characterize the Samburu pastoral system. It was only in Samburu central endowed with good rainfall that the pastoralists graze around their homes all year round. The spatial analysis indicate that rarely do livestock in Samburu east graze around homesteads due to low rainfall received and degraded pastures. The herds spatial distribution patterns

followed pasture availability as shown by vegetation NDVI patterns. Areas with higher NDVIs of over 0.3 attracted herds concentration but with high in situ mobility to maximize on grazing of the most nutritious pastures. Irregular rainfall pattern makes animals to move around the area in search of grass and water, and grazing patterns are always shifting. Among the livestock, goats were identified to have the most economic importance. On the other hand Pestes des Petits Ruminants (PPR), Foot and Mouth Disease (FMD) and Camel Trypanosomiasis diseases were identified to have the highest impact on pastoral livelihood. Pestes des Petits Ruminants (PPR), Contagious Caprine PleuroPneumonia (CCPP) and Foot and Mouth Disease (FMD) were reported to have been increasing by 57.3% of the respondents (n=199), 66.0% (n=229) and 54.6% (n=189) of the respondents respectively. Spatial analysis indicated that all the disease hotspots were closely related to the distribution of herds during different seasons of the year. Correlations between the mean annual rainfall and selected livestock diseases was significant for East Coast Fever (ECF) (r = -0.767, p = 0.001, N = 15), Cattle Helminthiasis (r = 0.639, p = 0.010, N = 15), Cattle Anaplasmosis (r = 0.631, p = 0.012, N = 15) and Camel Pox (r = -0.646, p = 0.044, N = 10). There was a strong relationship between seasonality and livestock disease epidemiology. In conclusion, there has been general change in rainfall and temperature trends which have had negative impacts on the pastoralists and their livelihoods. This study proposes grazing management embedded in observed herd mobility and grazing resource use patterns as a strategy towards adapting the pastoral communities to the changing climate and the focusing of disease control efforts towards the hotspots in the wet season and dry season grazing areas.