BackgroundRegion: Luangwa Valley, Zambia
The Thornicroft’s giraffe is a morphologically distinct population of giraffe endemic to the Luangwa Valley in Zambia. The population is biologically isolated from other giraffe and as such is ecologically and potentially genetically unique. With recent genetic studies showing that groups of giraffes across Africa are reproductively isolated from each other and potentially distinct species, the endemic Thornicroft’s giraffe may prove to be a unique species which would further highlight the need for increased conservation and management of its unique genetic heritage. As an iconic symbol of Zambia, the Thornicroft’s giraffe is an important tourism drawcard for visitors to the country and thus an economic asset for Zambia.
Despite its prominence, limited monitoring and research has been undertaken on the endemic Thornicroft’s giraffes with the last study published in 1978. The Zambian Wildlife Authority (ZAWA) and International Giraffe Working Group (IGWG) have both identified that the Thornicroft’s giraffe as of high conservation priority.
ObjectivesThere is currently no baseline estimate of population numbers for the Thornicroft’s giraffe and as such the real conservation status of this endemic giraffe subspecies is unknown (i.e. whether it is stable, increasing or decreasing). The results of this study will provide a baseline estimate of the current population size of Thornicroft’s giraffe.
The knowledge obtained from this research will be incorporated into the long-term wildlife monitoring programmes of the Zambian Wildlife Authority (ZAWA) and non-government organisations such as the South Luangwa Conservation Society (SLCS) with the aim of better enabling sustainable management of wildlife populations in partnership with local stakeholders. The protocol developed to census this population and produce the population estimate will hopefully be used to census other giraffe populations across Africa.
Important training of ZAWA and local community game guards in field census and monitoring programmes is a key element of the project to help better understand the historical and current status and range of the Thornicroft’s giraffe. In both field visits, training of local staff and interested parties are a key element of the project with the intention of creating a long-term project following the first year of work.
MethodologyThe investigations intend to provide an overview of the giraffe populations in each of the project areas, their social structure and dynamics.
The overall aim of the project is to establish methods (walking and driven transects) and undertake baseline censusing of the Thornicroft’s giraffe population to provide a basis for which long-term monitoring and analyses can be undertaken by ZAWA staff in collaboration with partners such as the IGWG, SLCS and others. Genetic sampling of a subset of the population will be undertaken, using remote biopsy sampling, to assess population genetic structure and species status of the Thornicroft’s giraffe population.
The information obtained from the aims of this project will be combined and implemented at a practical management level, with the aim of better enabling sustainable management of wildlife populations in partnership with the relevant stakeholders.
- Preparation for the project and initial expedition, collaboratively developed with ZAWA and SLCS (already ongoing)
- Initial expedition – Genetic and population census
- Analysis of genetic samples and census data, report writing and publishing, and planning next phase of the project
- Preparation for the next expedition, collaboratively developed with ZAWA and SLCS
- Second expedition – focus on population census and training
- Analysis of population census data, report writing and planning next phase of the project
- Feedback of next stage management and conservation objectives to ZAWA and partners with regards to the giraffe population
The first expedition – genetic and population census – took place in July 2008 which is the peak period for giraffe to congregate in preferred habitats. The second expedition is proposed for early 2009 following the analysis and reporting from the first. Long-term, the programme intends to develop this project into a key collaborative project between IGWG, ZAWA, WCS, SLCS and other interested partners, and further long-term funding/support will be sought following this initial project.
Wilderness Safaris Trust funding has enabled a number of the key elements to be supported for this project and its ongoing management e.g. support for flights, food, accommodation and equipment.
The Expedition took place in July 2008 and was accomplished using two methods: Distance sampling and genetic sampling. The information obtained from the two aims of this project will be combined and implemented at a practical management level, with the aim of better enabling sustainable management of wildlife populations in partnership with the relevant stakeholders.
The distance sampling method was used to estimate giraffe densities, as well as eight other important large mammal species identified by ZAWA for the Luangwa Valley: African elephant, buffalo, lion, leopard, wild dog, hyaena, wildebeest and kudu. The surveys were conducted by road transect during the Dry Season, in July 2008. The road transects were located inside the South Luangwa National Park and outside in the Lupande Game Management Area, and across a range of habitat types e.g. open savannah, riverine and dense scrub.
The non-intrusive access to this area provided the team with the ideal opportunity to conduct wildlife density and population survey. The objective of the research was to record numbers and GPS locations of giraffe, and eight other focal mammal species.
These results are being analysed and used to produce wildlife densities in the surveyed areas.
Additionally, the research involved the collection of genetic samples (42 separate individuals in total) using remote biopsy methods to undertake analysis of the giraffe genetics in comparison to other populations across the continent. This work will potentially highlight the importance of this population as genetically unique which in turn should increase its priority for long-term conservation and management support.
Tissue biopsies provide the greatest quantity of high quality nuclear DNA of any biological samples that can be secured readily from free-ranging individuals. Samples for DNA analysis were collected from a random subset of the endemic Thornicroft’s giraffe population in Zambia’s Luangwa Valley using a remote biopsy dart delivery system to assess the genetic ‘health’ and DNA structure of the population.
A sample number of 42 equates to approximately 5% of the Luangwa Valley population which will provide a good example of the cross-section of the population considering they were collected randomly and inside and outside the South Luangwa NP.
With support from WCS-Zambia the genetic samples safely arrived in Omaha, Nebraska, USA at the Henry Doorly Zoo Centre for Research and Conservation where they have been ‘cleaned’ and ‘banked’. The geneticist at the zoo – Dr Rick Brenneman, also a member of the International Giraffe Working Group, will work with colleagues over the coming months to analyse the samples and compare them with the datasets from across the continent. It is hoped that this work will be finalised a report furnished to ZAWA and other colleagues by the end of 2008, and following that a scientific paper submitted to an international peer-reviewed journal. Analysis of the giraffe distance sampling will also be undertaken and should help to provide an estimate of giraffe density in the area surveyed during the study period.