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Climate change will lead to extreme droughts, but it is difficult to predict how this will affect crop pests. In particular, it is unclear how interactions between natural enemies and pests will be influenced. In the field, bird cherry-oat aphids (Rhopalosiphum padi (L.)) have been observed to reside close to, or below the ground surface during dry conditions. We hypothesized that this will increase the niche overlap between R. padi and ground-dwelling predators such as carabid beetles and wolf spiders and that aphid numbers will therefore decline during dry conditions. A fully factorial mesocosm experiment was conducted testing the combined effects of drought and predator presence on aphid position and abundance on barley (Hordeum vulgare) plants. In support of our hypothesis, we found that (a) aphids moved below ground during dry conditions, (b) predators reduced aphid numbers, but only during dry conditions, and (c) predators reduced the proportion of aphids below ground in dry conditions. This increased predation effect during dry conditions was, however, compensated for by a corresponding increase in aphid performance on the plants and so the net effect of drought on aphid numbers ended up being neutral. Thus, pests can be affected by drought in complex ways via a combination top-down and bottom-up mechanisms. Predicting how pest populations will be affected by droughts in the future is thus a formidable research challenge.

Human-wildlife conflict (HWC) is a common problem for many farming communities around protected areas like parks, reserves and forests all around the world. In Kenya where most farming occurs at smallholder levels, HWC:s could be highly significant as it may lead to a complete loss of crops and livestock. Such cases have previously been experienced by smallholder farming communities around Mt. Kenya national park/natural forest, but many have gone unreported. To minimise these conflicts, the government of Kenya, in collaboration with the Rhino Ark Foundation have constructed an electric fence around the forest. The main aim of this study was to collate and document experiences of crop raiding by wildlife on small holder farms in Embu County, Kenya that are adjacent to the forest. It also aimed at evaluating the effectiveness of the electric wildlife fence along the forest line through Embu County. To achieve this, questionnaires were administered to 181 small holder farmers living and farming within 5 km of the electric fence on the approximately 60 km long forest line. The questionnaires sought to gather information on the wildlife species causing damages, the magnitude of damage suffered by the farmers on the crops and livestock before and after the construction of the fence, the interventions they have in place to prevent such damage and other suggestions to prevent wildlife raids. Wildlife cameras were also used to track wildlife activity at night time. A total of 169 questionnaires were retrieved and 455 pictures downloaded from the cameras. Results show that the percentage of crops destroyed by wildlife was significantly higher in the year before the wildlife fence was constructed in 2016 compared to the period after the fence (2016-19). Currently the naked mole rat (Heterocephalus glaber) and the Kenyan African (Tachyoryctes ibeanus) were reported as the most frequent pests on crops after the fence construction. Elephants were the most severe crop raiders before the fence construction, but their raiding ceased completely after the fence installation. The white tailed mongoose (Ichneumia albicauda) and eagles (Accipitridae family) were the most frequently reported raiders on livestock. Maize, macadamia and bananas were the most commonly targeted crops while chickens were the most targeted livestock. Over 90% of the farmers indicated that the fence significantly contributed to a reduction of HWC:s. However, they also suggested additional fencing for both crops and livestock, as well as trapping and poisoning of raiders like moles and mongooses that were responsible for most of the crop damage and livestock attacks. This study recommends that farmers devise innovative ways of dealing with the threat of small animals. These may include aggressive fencing and growing crops and keeping livestock that are not targeted by small animals. It is also recommends that the Kenya Wildlife Service (KWS) develop innovative ways of compensating affected farmers and prevent further loss. The KWS may also train farmers on procedures to follow in reporting cases of wildlife invasion and on food choices of various wildlife species inhabiting the forest so that they avoid growing crops or keeping livestock that are prime targets for wildlife.

Deforestation is a driver of land degradation and a major environmental problem in Somalia, and has been linked to frequent incidences of drought over the years. Monitoring of changes in forest cover is therefore critical for the country’s environment. The problem of land degradation has been worsened by the large scale charcoal production that is witnessed in the country. This study aimed at estimating forest cover change between 2000 and 2019 in Somalia using Landsat-based forest cover datasets. Google Earth Engine (GEE), a cloud based computing system was used to provide a platform for this analysis. Based on the 30% threshold recommended by International Geosphere Biosphere Program for differentiating forest from non-forest trees, approximately 23% forest cover loss was found, from 87, 294 hectares in 2000 to 67, 199 hectares in 2019. Most of the country’s forest is within the southern and central parts of the country, and significant forest cover losses occurred mainly around Mogadishu and Kismayo port throughout the study period. There is therefore a need for the Federal Ministry of Environment and environment ministries in the federal member states to design mechanisms and strategies for restoration of the degraded forests and to curb deforestation.