Leeuwenonderzoek in Kenia in 2019: Samenvattingen van studentenverslagen

Afgelopen jaar hebben verschillende studenten van de Universiteit van Leiden onderzoek gedaan naar leeuwen in verschillende nationale parken in Kenia. Deze onderzoeken werden gesteund door Stichting Leo. Ondertussen zijn de rapporten af, en we willen de resultaten graag met jullie delen door middel van onderstaande samenvattingen.

Josine Meijer – The effect of human disturbance on lion movement patterns and home ranges in and around Nairobi National Park, Kenya

The lion (Panthera leo, L. 1785) population worldwide has been on the decline for decades, with the leading causes being habitat destruction, prey depletion and human-lion conflicts. Contrastingly, research that studied the effect of habitat destruction on lion movement are scarce. In this study I investigated the effect of habitat destruction on lion movement patterns, to gain a better understanding of human disturbance on lions. In 2017 and 2018, the Kenyan government built a railway bridge that cut straight through Nairobi National Park. Using GPS data from collared lions and using geospatial analysis, I investigated if the railway bridge or construction thereof has had an effect on the lions’ movements and home range. Construction works had a significant effect on the lions movement. The lions tend to keep a further distance from the bridge during constructions and were found outside of the park more often. Furthermore, potential minimum distance moved per 24 hours and home range sizes decreased substantially during and after construction of the bridge. No restoration of the movement patterns was found. The railway is expected to be in full operation in 2019. This study concludes that the construction of the bridge seems to have had an impact on the lion population in Nairobi NP. However no conclusions can be drawn for long term impacts of the presence of the bridge. Further research is needed to determine if lions are also impacted by the presence of the bridge when it is in use.

Megan Verhagen – The influence of prey species abundance on prey selection and diet composition of Panthera leo in Kenya: a DNA-analysis.

The African lion is under increasing pressure and has faced dramatic population declines in the past 21 years which are expected to continue. To preserve the African lion it is suggested that in the near future only fenced protected intensively managed areas may save lion populations. However,
conservation success of management practices is dependent upon many different factors which all may contribute to or counteract the success of conservation efforts. One of these factors is diet composition. The diet composition of lions provides insights in predator-prey dynamics and lion
population demographics. The optimal foraging theory predicts that predator diet composition will vary along with the abundance variations of the prey species. Since lions are opportunistic predators, it is expected that prey species abundance influences their diet composition. However, in small reserves with unnatural ungulate assemblages, the connection between prey species abundance and diet composition are not as distinct. Consequently, for the purpose of conservation management, especially in in enclosed protected areas, it is essential to gain a better understanding of the influence of prey species abundance on prey selection by lions. A diet analysis is proposed for which the traditional methods of hair analysis and opportunistic observations are used in combination with a DNA-analysis through NGS. This study will be carried out in 4 different national parks in Kenya which were selected for their differing management strategies.

Sam Boerlijst – Genotyping the lion, The usability of microsatellite genotyping of faecal samples

1. Biodiversity is declining at an alarming rate. Adequate conservation is needed in order to mitigate damage to ecosystem stability and functioning. Even more so due to the increasing pressure of climate change, habitat fragmentation and overexploitation.
2. Protected areas have been established worldwide as a tool for conservation of biodiversity. However, conservation of wide-ranging carnivores in particular remains a challenge. Due to the pressure of habitat loss, prey base depletion and increasingly dense inhabited buffer zones of national parks, human-wildlife conflicts have dramatically increased. This has led to a severe decrease of the African lion (Panthera leo, see Kitchener et al L. 1758) populations.
3. Recent research has demonstrated that in fenced parks lion populations may have a higher chance to survive by limiting prey dispersal and human-wildlife conflicts.
4. The effectiveness of enclosing reserves can be studied via dietary analysis. However, traditional methods are prone to oversampling of a few individuals, which may lead to biased results, thereby revealing individual dietary changes instead of those of the species.
5. This study aims to provide a method to assess individual diet via molecular identification of scat samples in Nakuru National Park and Soysambu Conservancy using microsatellite variant calling from capillary electrophoresis or next generation sequencing data.
6. Insight in the usability of microsatellite analysis for faecal samples can be used to more accurately determine population size and individual diet, which may help to determine the effectiveness of fenced reserves in regards to livestock predation.