Dynamics of net primary production and food availability in the aftermath of the 2004 and 2007 desert locust outbreaks in Niger and Yemen

Abstract: The knowledge of desert locust plagues goes back to biblical times but it is just as relevant in 2020 with an ongoing outbreak in East Africa and the Middle East. The locusts pose a threat to agriculture, and by extent food availability, due to their high appetite, diverse diet and ability to migrate long distances in large swarms. More knowledge of the aftermath is required by the international donors to motivate their continued funding for locust control to prevent and fight future outbreaks. As many countries in the affected areas lack the economic resources to fund full-scale control measures, monetary contributions from donors are crucial. This master thesis aims to contribute to this topic by investigating the impact the 2004 and 2007 locust outbreaks had on net primary production (NPP) and food availability in Niger and Yemen, which are two of the poorest countries in the region. This is done with the use of a comparative and exploratory approach using geographical information systems, remotely sensed images and statistical methods. Key datasets in this thesis includes information on known locust locations, livelihood zones as well as food availability indices. The result shows a decrease in NPP within both croplands alone and within all land cover types combined during the years of the outbreaks. The decrease was larger in Niger 2004 than in Yemen 2007. A reduction in NPP was also observed within all livelihood zones in Niger and almost all in Yemen. It can be seen that the decrease was greater closer to the known locust locations, which implies that the locusts did have an impact. Food indices in Niger 2004 showed an overall decline in food availability at the time, possibly in relation to the outbreak. The result of food indices in Yemen was less prominent as the country imports 75% of its food and is therefore more resilient against decreased food availability from national production compared to Niger. Factors other than locusts could be the reason, or partly the reason, for the decreases in NPP and food related indices seen in the result. However, the incidents coincide in time and space and a relationship between them is possible. That said, the results of this thesis constitute a step towards generating knowledge about the consequences of the locust outbreak and presents a foundation for such research to be continued and improved upon. This is particularly relevant in light of the fact that donors often require more evidence of the negative impacts caused by locusts as a condition for receiving additional funding to combat future outbreaks.