Genetic management of wildlife in Kenya: focus on dung DNA of black rhinos in the Chyulu Hills

 

The use of dung DNA analysis for determining the genetic make-up of black rhinos is a new, cutting edge technique in Kenya, and is introduced to improve the country’s wildlife management. This pioneering method has proven to be invaluable for surveying rhino demographics and their genetic status, enhancing the conservation efforts for this endangered species. Kenya is home to 12% of Africa’s endangered black rhino, and 85% of the Eastern black subspecies. Sound biological and genetic decision making and management of these animals is therefore vital for ensuring the sustainability the country’s natural resources. The aims of the proposed project are two-fold:

• Build Kenyan Wildlife Service’s capacity in rhino conservation genetic studies and management through training in molecular genetic analysis
• Assess the genetic make-up of a rare, indigenous rhino population in the Chyulu Hills, southern Kenya

In Kenya all wildlife belongs to the Government and is officially managed by the Kenya Wildlife Service, who has recently introduced dung DNA work in their rhino management plan. The proposed project will study the genetic make-up of a small fragment remnant black rhino population that inhabits the Chyulu Hills in southern Kenya to a) use the study as an advisory and guidance example for KWS to build capacity within this field b) determine the structure of this population for improved biological management.

The project will be executed as a partnership initiative between KWS, Manchester Metropolitan University (MMU) and University of Liverpool (UoL), with the latter two organisations providing expert training and guidance in techniques for molecular genetic analysis. The goal is to train a person from within KWS to undertake such studies, for the benefit of the rhinos in the Chyulu Hills and other rhino conservation genetic studies in Kenya and in neighboring East-African counties.

The rhinos inhabiting the Chyulu Hills are the remnants of a much larger population that was almost completely exterminated in the poaching debacle of the 1970s and early 1980s, and only survived as a result of the extremely dense lava-strewn forest that covers the area. The Chyulu population is thought to be the only surviving indigenous population of rhinos; all the others have been reintroduced. It therefore presents a unique opportunity to study a distinct group, determine genetic diversity, and inform future management plans.

They are currently managed by partnership initiative between the Kenyan Wildlife Service (KWS) and the Maasailand Preservation Trust (MPT). Both organisations deploy anti-poaching and monitoring rangers to safeguard this rare and genetically important population of approximately 12-15 rhino.

The terrain in the Chyulus is difficult, due to the thick vegetation covering the area, and rhino sightings are rare and usually brief. Therefore most monitoring is achieved through indirect sightings (recording bite, footprint and dung sightings). As a consequence very little is known about the structure of this important relic population: its numbers, sex structure, effective population size, levels of interbreeding, levels of genetic diversity and the genetic distance to the rest of Kenya’s rhino population are unknown. In order to make effective management decisions for this small, fragmented population, a precise knowledge of these factors is required. It is therefore planned to undertake microsatellite and sex gene analysis on DNA extracted from rhino dung. The information is also vital for rhino conservation on a larger continental scale, as it will enable factors relevant to the viability of the population to be qualified and enable management decisions to be made, for example whether to reinforce this small population by introducing animals from other populations (and different gene pools) and as a result increase overall rhino numbers. 

An integral component of the project is capacity building by training Mr Antony Wandera (KWS) in molecular genetic analysis and thereby building this capacity within the Kenya’s wildlife management. Once trained in the field, through the example at the Chyulu Hills, he will be able to undertake similar studies across Kenya, and thus inform Kenya’s conservation decision-making process, especially those relevant to rhinos. As part of the project, Antony will enroll on an MSc in Conservation Biology at the Metropolitan University in the UK and will hereby receive expert tuition and direct field work experience, which after completion of his studies will be rolled out in other rhino projects. 

As a result of the project, KWS will have an internal expert in rhino dung DNA analysis who will be able to use the technique in other Kenyan and East-African rhino management projects leading to improved wildlife management decision making. Furthermore, and on a more local level, a clear picture of the genetic structure and make-up of the Chyulu rhinos will be obtained, and will be used in management decisions regarding this relic population.

The secondary aims of the project, in relation to the work at the Chyulu Hills are:

• To establish the minimum number of individuals in the population through probability of identification based on microsatellite genotypes
• To determine the sex of all identified individuals by analysis of Y- specific restriction digests of the ZFX/Y gene
• To reconstruct pedigrees and determine levels of inbreeding
• To determine the effective population size
• To examine rank-order relatedness between breeding males in the population
• To determine levels of genetic diversity present in the two study populations through microsatellite and mtDNA analysis
• To compare levels of diversity found in study population with those found in other extant Kenyan populations and with museum samples
• To calculate the genetic distance between the study population and other extant populations in Kenya
  

Funding has been provided by the EAZA Rhino Campaign, Chester Zoo, Amneville Zoo, the Kenya Wildlife Service, Manchester Metropolitan University and Save the Rhino International. Work began in October 2007 and the results are expected in a year's time.