The Effect Of The New Standard Gauge Railway (Sgr) On Elephant Movement In Tsavo Ecosystem, Kenya (March 2016 – March 2018) (2018)

In 2014, the Government of Kenya initiated construction of the Standard Gauge Railway (SGR) linking Kenya’s largest port city, Mombasa, and her capital city, Nairobi.


Save The Elephants, Kenya Wildlife Service


Koskei M., Okita-Ouma, B., Lala, F., Mwazo A., Kibara D., Tiller L., Pope F., King, L., Douglas-Hamilton I.

Date Published 2018-Tsavo-tracking-and-monitoring-2-year-report-final-web

Save The Elephants & Kenya Wildlife Service


In 2014, the Government of Kenya initiated construction of the Standard Gauge Railway (SGR) linking Kenya’s largest port city, Mombasa, and her capital city, Nairobi. The construction of the Mombasa – Nairobi SGR was completed and officially launched for use in June 2017. The SGR cuts through the 23,000 Km2 Tsavo National Parks comprising Tsavo East and Tsavo West National Parks, and is home to the largest single elephant population in Kenya, numbering approximately 13,000 animals (2017 total aerial count) as well as other mammalian species. Save the Elephants (STE) in partnership with Kenya Wildlife Service (KWS) fitted radio tracking collars on ten Tsavo elephants in March 2016. The main objective of this project was to understand the potential impact of the new SGR and highways in Tsavo on elephant movement and the effectiveness of the mitigation measures put in place to maintain ecosystem connectivity. A further 20 radio tracking collars deployed in February 2018 is expected to enrich these data we are collecting. However, this report documents findings from the initial ten collars deployed in March 2016. In this report, we explore movement patterns and hotspots of elephants’ use in relation to the new SGR and the Voi – Taveta highway after two years of tracking. The home ranges of some elephants crossing the SGR extends from Yatta plateau in Tsavo East to beyond Mkomazi National Park in Tanzania. Out of the eight elephants collared along the SGR; six of them (some with their families), have managed to cross the SGR during the two years of monitoring. The two most frequently used SGR crossing points for the tracked elephants in Tsavo were the Maungu corridor and at the Manyani corridor. The two corridors are one of six SGR underpasses designed specifically for wildlife use. The monitoring of wildlife utilization of SGR crossing underpasses by KWS patrols teams have shown that, through direct animal signs such as footprints and dung, elephants are learning relatively quicker to use the underpasses than other wildlife species. Movement patterns of the collared elephants also show that the erection of double electric fence, SGR fence and David Sheldrick Wildlife Trust’s fence at Ngutuni, has completely blocked elephant movements to the high-usage area between the SGR and the Mombasa highway. Elephants attempting to cross over the SGR and highway from Ngutuni Conservancy towards the Sagalla farms have also had their movements curtailed. The monitoring of the SGR, on foot or by vehicle, for wildlife crossing shows that elephant movements have been greatly impacted by the fragmentation of the habitat and blocking of normal migration routes. Some of the tracked elephants spent more than a year moving up and down along the SGR, but were not able to cross it after two years. The analysis of the mean speed in elephant tracking data indicates that elephants are slower crossing the existing Mombasa highway than the new raised SGR. One of the major challenge facing the underpass utilization by wildlife is the proliferation of illegal human settlements along the SGR and near the main underpasses. This applies especially to the Voi – Bachuma section of the SGR, around Ndara and Maungu areas. The other notable threat to wildlife use of the SGR underpasses is the high influx of livestock recorded going into the park through those underpasses. We also identified in this study that elephants are attracted to the borrow pits not completely filled after construction, along the SGR. The borrow pits collects and avail water to elephants and other wildlife species, but may expose them to potential train and vehicle accidents.

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