3 research outputs found
The role of ants in structuring insect communities on the canopies of senegalia drepanolobium near Laikipia, Kenya
In the black cotton ecosystem of Laikipia, Kenya, four symbiotic ants coexist at a fine spatial scale on canopies of Senegalia drepanolobium. They exhibit different aggressive behaviours and modify their tree canopies differently. These diverse behaviours were expected to affect the associated canopy arthropod communities. At the Kenya long-term exclosure experiment (KLEE) and its immediate environs at Mpala Research Centre, Laikipia, the insect communities coexisting with each of the four ant species were characterized, and their response to different vertebrate herbivory. Other ant species inhabiting the tree canopies or the ground were surveyed too. Pitfall trapping was used in sampling terrestrial ants, while beating and mist-blowing were used in collecting arboreal insects. Different sampling methods had varying efficacies, revealing the importance of using several methods. There are at least sixteen ant species in this ecosystem, all occurring on the ground, but only ten species on the trees. Terrestrial ant communities in this ecosystem cannot be used as indicators of grazing pressure for range management. A total of 10,145 individual insects were collected from the tree canopies, comprising of 117 species from seven orders and 25 families, forming a complex community of species interacting at different levels. Symbiotic ant species had a significant effect on insect community structure and composition. Crematogaster sjostedti was associated with a community that was significantly different from the other ant species. There was no significant effect of vertebrate feeding pressure on the canopy insect community, but there was an interaction effect between ant species and treatments. Significant differences between ant species mostly occurred on treatment plots where only cows were allowed to graze. One or more of the ant species may be a keystone species in this ecosystem even though experimental manipulations failed to confirm earlier findings. It was concluded that the one-year period during which experimental manipulations were carried out was not long enough to reflect takeover effects on the insect community. The four symbiotic ant species colonizing S. drepanolobium comprises of two guilds, the hemipteran-tending ants (C. sjostedti and Crematogaster mimosae) and non-tending ants (Crematogaster nigriceps and Tetraponera penzigi). Communities associated with these guilds were found to be significantly different in all four diversity indices. The black cotton ecosystem is species-poor compared to other ecosystem such as forests. The number of insect species that colonizes S. drepanolobium and coexists with acacia-ants forms a large proportion of the invertebrate community. Therefore, this ecosystem should be conserved to safeguard this invertebrate community. This will also give scientists a chance to establish how the various insect species coexist with symbiotic ants on tree canopies
A Policy Brief on Adopting the Somali Camel for Enhanced Profitability and Pastoral Resilience in Northern Kenya
Persistent drought and high temperatures in Isiolo and Marsabit counties of northern Kenya repeatedly devastate livestock herds particularly cattle making the pastoralists less resilient, more vulnerable to climate change and poor. To address this challenge, an IGAD funded project promoted adoption of Somali camel breed, trained farmers on improved management and also estimated potential profitability of rearing the camel. Through the project, trainers were trained and facilitated to train 240 peri-urban Somali camel producers in Isiolo and Marsabit on breeding, health, routine husbandry and marketing. Impact study documenting positive stories of change was conducted at the end. Producers who hitherto made zero money from their camels were making KES. 42,000 a month from sale of 20 litres of milk daily from only 5 milking camels; producers had adopted a new grazing management strategy that ensured daily access of the camel milk market and conservation of grazing areas around settlements; motor bikes had been adopted as means delivering milk to collection centers thus creating jobs for the youth; the beneficiary producers were spending more money on production inputs. In terms of policy, the county governments of Isiolo and Marsabit need to appreciate the huge business potential in Somali camel rearing and the magnitude of positive change that can be brought about by capacity training of producers on improved camel management technologies and agree to allocate more funds in support of livestock production extension services
Human myiasis in rural South Africa is under-reported
Background. Myiasis is the infestation of live tissue of humans and other vertebrates by larvae of flies. Worldwide, myiasis of humans is seldom reported, although the trend is gradually changing in some countries. Reports of human myiasis in Africa are few. Several cases of myiasis were recently seen at the Mthatha Hospital Complex, Mthatha, Eastern Cape Province, South Africa (SA).Objective. Because of a paucity of literature on myiasis from this region, surgeons and scientists from Walter Sisulu University, Mthatha, decided to document myiasis cases presenting either at Nelson Mandela Academic Hospital or Umtata General Hospital from May 2009 to April 2013. The objective was to determine the incidence, epidemiology, patient age group and gender, and fly species involved. The effect of season on incidence was also investigated.Results. Twenty-five cases (14 men and 11 women) were recorded in the 4-year study period. The fly species involved were Lucilia sericata, L. cuprina, Chrysomya megacephala, C. chloropyga and Sarcophaga (Liosarcophaga) nodosa, the latter being confirmed as an agent for human myiasis for the first time. The patients were 3 - 78 years old (median 56). Cases were most numerous during spring and summer, and were associated with underlying pathologies typical of ageing.Conclusion. Myiasis is a more common medical condition than expected in the Mthatha region. The study shows that human myiasis is still frequently encountered in SA, and there is a need to understand its epidemiology better