Understanding the Status and Ecology of Nubian Giraffe in Kidepo Valley National Park, Uganda5/30/2018 The vast savannahs and striking mountainous terrain of Kidepo Valley National Park provides a stunning backdrop for a historically significant population of Nubian giraffe. This rugged landscape is home to one of only two remaining naturally occurring populations of giraffe in Uganda. The current Kidepo Valley National Park population, however, is only a small remnant of its prior size. What was once the historical stronghold of giraffe in Uganda, the Kidepo Valley National Park population was decimated by a period of civil unrest and intense poaching, bringing this important population to the brink of local extinction. Despite stabilization in the region and heroic conservation efforts of the Ugandan Wildlife Authority, giraffe in Kidepo Valley National Park have not returned to their previous population size. Recognizing the need for reliable ecological data to inform conservation strategy, the Giraffe Conservation Foundation and partners developed a conservation monitoring programme in 2015. This programme has grown from its early foundations in establishing baseline data on population size, structure and distribution to including a comprehensive population genetics study and a cutting edge GPS telemetry study to better understand the movement ecology of these giraffe. In April of 2018, a team of researchers and conservationists again traveled to Uganda’s frontier region to continue this study deepen insights into the ecology of giraffe in Kidepo Valley National Park and identify threats to this critical population of Nubian giraffe. Current Research Efforts in Kidepo Valley NP Nubian giraffe in Uganda are currently estimated to number <1,300 individuals remaining in the wild across Murchison Falls NP, Kidepo Valley NP and Lake Mburo NP. Conservation research on the Nubian giraffe has been identified as a conservation priority by GCF and the IUCN SSC Giraffe & Okapi Specialist Group, and GCF in partnership with Uganda Wildlife Authority (UWA), Uganda Wildlife Education Centre (UWEC) and Dartmouth College have worked together in Uganda since 2013. This conservation programme seeks to build on the first three annual comprehensive assessments of Nubian giraffe numbers in Kidepo Valley NP undertaken by GCF, UWA and partners since 2015. The Kidepo Valley NP giraffe population likely faces the hallmark threats of a small, recovering population potentially including inbreeding depression from a genetic bottleneck and top down population regulation. Given the estimated small population size, it is susceptible to demographic and environmental stochasticity, requiring a close monitoring of population dynamics to quickly identify and mitigate potential and emerging threats. This survey provides an invaluable update on the initial baseline collected to address gaps in knowledge for the IUCN Red List Assessment of the Nubian giraffe, as well as for the implementation of the first-ever draft National Giraffe Conservation Strategy and Action Plan in Uganda 2017-2027. Project Objectives – April 2018 1.To re-survey the Nubian giraffe population size, distribution and threats in Kidepo Valley NP. 2.To collect additional DNA tissue samples from Nubian giraffe in Kidepo Valley NP to better understand social relationships. 3.To fit five GPS satellite units to Nubian giraffe in Kidepo Valley NP. 4.To provide additional recommendations on suitability for translocating a new founder population of Nubian giraffe to Kidepo Valley NP in August-September 2018. 5. To provide ongoing capacity building and support to UWA monitoring staff in Kidepo Valley NP. 6. To provide valuable data for the ‘living’ Uganda country-wide status report and Uganda’s draft National Giraffe Conservation Strategy and Action Plan 2017-2027.\ Population Monitoring Methods The primary data collection method for population monitoring was a vehicle-based fixed route photographic survey to obtain a total count of giraffe over the survey period. Since each individual giraffe has a unique pelage pattern, photographs of observed giraffe were compared with previously photographed giraffe to ensure that repeated sightings of an animal did not result in increased population estimates. We conducted surveys daily between 8-10 April 2018, from approximately 8:00am to 4:00pm during each day Using survey routes and protocols established in 2015, the southern section of the Park was identified in the Kidepo Valley NP as the preferred habitat for giraffe. We used three survey teams to drive each route during every survey day, ensuring complete coverage of the Park’s road network over all survey events. three vehicles during each survey period: (1) North - north of Apoka, (2) South - south of Apoka, and (3) East- east of Apoka. Each survey vehicle had a driver, a research team with survey equipment, and an UWA ranger. The UWA rangers proved invaluable in guiding the survey teams to vantage points within the Park along the various routes. Their knowledge of the Park allowed us to track the giraffe so to get close enough to photograph and/or identify them. When giraffe were encountered, photographs were taken of all individuals and the location, age class (Calf: 0-1 year; Subadult: 1-5 years; Adult: 5+ years), sex, group composition, injuries and any visible signs of disease were also noted. Using pattern recognition software, the database of unique individual giraffe in the Park was updated to include observations from 2015-17 surveys and was subsequently added online to GiraffeSpotter (www.giraffespotter.org). As part of long-term monitoring, the capture history records of individual giraffe were generated from repeated photographic surveys which enable the monitoring of both individual space-use and population distribution over time. All individual giraffe encounter and matches were visually confirmed by researchers to ensure positive identifications. Results During the survey period, we documented 86 giraffe observations and 17 group observations. From these encounters, we identified 35 unique individual giraffe in the Park, including three newly identified calves/subadults. Two calves encountered in 2017 were not resighted during the 2018 surveys. The current population structure is skewed towards adult, which is consistent with other healthy ungulate populations and the sex ratio is 1.18 males/female, suggesting no sex bias in survival parameters (Table 1). None of the observed giraffe showed any sign of snare wounds or giraffe skin disease. All giraffe encounters were in the southern portion of the park, along the Narus Valley. This spatial distribution of encounters is consistent with all prior GCF survey efforts with no giraffe encounters ever documented outside of the Narus Valley. All the data collected during these surveys will be added to the GCF Uganda giraffe Country Profile to help inform future conservation measures and the proposed development of a National Giraffe Conservation Strategy and Action Plan. In time, the information will also be incorporated into the IUCN Red List assessment of the Nubian giraffe. Spatial Ecology Methods To better understand the spatial ecology of giraffe in Kidepo Valley National Park and to inform Park-specific management strategies for the conservation of this flagship species, including future giraffe reinforcement translocations, we deployed five newly developed solar-charged GPS satellite tracking units on giraffe. This GPS tracking programme is part of an Africa-wide effort, Twiga Tracker, an initiative spearheaded by GCF working in collaboration with the Smithsonian, San Diego Zoo Global and Wildlife Conservation Alliance to better understanding spatial ecology of all giraffe species across the continent. GCF and partners undertook the first preliminary study of giraffe movements in Kidepo Valley NP during 2016-17, testing the newly developed GPS satellite units. To build a baseline of understanding giraffe spatial ecology in the Park, we fit five additional giraffe with ossicone mounted GPS satellite tracking units (Fig 3) in April 2018. These solar charged tracking units were designed by the Kenyan based company, Savannah Tracking, and were programmed to record coordinate fixes at one hour intervals. Spatial data are uploaded to a server via Iridium satellite uplink twice daily to allow for real-time monitoring of tracked individuals. Collaring operations took place on April 11 and April 12. The immobilization and collaring team consisted of two UWA veterinarians, one technician, UWA wardens, UWA rangers and UWA drivers, supported by individuals from GCF, Dartmouth College, Chester Zoo, Columbus Zoo, and Cheyenne Mountain Zoo. All giraffe were immobilized using a combination of Etorphorine and Azaperone, with dosages commensurate with the estimated body size. Once the giraffe was secured on the ground, the reversal was immediately administered. Each giraffe was restrained for approximately 15-20 minutes while the GPS unit was fixed. Each GPS unit was attached to the ossicone using 2 surgical steel bolts and nylon webbing. While the giraffe was restrained, we also collected morphometric data as well as tissue and blood samples. All giraffe were monitored following fitting the units to ensure they were behaving normally and that they exhibited no signs of injury or distress. All giraffe safely returned to their respective herds after they were released. The UWA monitoring team in Kidepo Valley NP will continue monitoring of the giraffe as part of their field programme. Results Preliminary data from the GPS satellite units has been mapped and presented below (Fig 4.) The exhibited movement behaviours from tracked giraffe are units are consistent with the spatial distribution of giraffe herds exhibited during surveys in that movement appears to be restricted to within the Narus Valley of the southern half of Kidepo Valley National Park. Most giraffe have exhibited tortuous movement in the densely vegetated areas along the eastern and western edges of the park with more linear movements along the river valley. Additionally, movement behaviours have begun to reveal insights into fission/fusion dynamics of giraffe social behaviour. Although the collared giraffe were in three distinct herds during the collaring operations, tracked individuals regularly converged and separated over the duration of the tracking period. Conservation Outcomes Kidepo Valley NP is home to the second largest Nubian giraffe population in Uganda, and as such, conservation strategies for this unique taxon hinge on a detailed understanding of their population dynamics and ecology. Our broader and ongoing evaluation of their numbers and current threats to the population in Uganda in collaboration with UWA and UWEC, and technically supported by Dartmouth College (USA) has to date provided valuable outputs, including the translocation of 15 giraffe to Lake Mburo NP (new calves have been born), 37 giraffe to the south side of Murchison Falls NP (new calves have been born), population surveys and monitoring in all Parks, and the development of a draft National Giraffe Conservation Strategy and Action Plan. The findings from this project have already provided a critical baseline to help with future conservation efforts for Nubian giraffe in the Park, as well as the country at large. Importantly, conservation translocation has been identified as a key tool to further secure Nubian giraffe numbers and range in Uganda. As an example, a detailed understanding of the population structure in Murchison Falls NP as a potential source population to supplement genetic diversity within the small Kidepo Valley NP is an essential component of safely removing individuals and using them to propagate viable populations in other areas of Uganda. GCF drafted a translocation viability assessment using the IUCN guidelines to help better inform UWA about this potential activity – as such UWA is key to undertake the operation in late 2018. Additionally, our current conservation research efforts in Murchison Falls NP and knowledge of group structure, preferred associations and social dynamics, coupled with detailed understanding of giraffe skin disease issues, should provide for a social consideration when selecting individuals for translocations in the future. All this work has been initiated through this project and in future findings will help us to make informed recommendations and decisions. With the ongoing monitoring of the Kidepo Valley NP giraffe population, a better understanding of giraffe by all stakeholders can help to further develop their long-term conservation and management. Our work will continue to inform the implementation of the current draft National Giraffe Conservation Strategy and Action Plan for Uganda.
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