While black rhino populations in South Africa are still under threat, scientist are finding ways to boost their conservation through studying their genetics…
Analysing the DNA found in rhino dung may soon help managers make decisions that hold the key to the long-term survival of black rhino in South Africa.
With the help of genetic testing, postdoctoral research fellow in the Human-Wildlife Institute at the University of Cape Town (UCT) Nikki le Roex seeks to obtain information on black rhinos living in small parks in South Africa in order to inform black rhino management within these areas. Le Roex is currently setting up a Rhino DNA database in a sample population of black rhino within SANParks.
“SANParks identified a pilot population for this work, and we will complete the genetic analyses on this population before tackling other Parks,” says Le Roex.
Some of these Parks pose key challenges for authorities when monitoring black rhinos. Information from monitored black rhinos allows researchers to calculate vital population statistics that shows how well the rhinos are doing. In some instances, rhinos may also accidentally breed with close family members because of the few individuals living in a specific park.
To gather DNA samples within this pilot population, Le Roex, along with a senior ranger, collects fresh black rhino dung that is less than 24-hours old from rhinos. She then takes a few slices of the outer layer of the dung, where the rhino intestinal cells are found, and extracts DNA from these in the lab at UCT.
“Data analysis then determines individual identification, the level of genetic diversity and inbreeding within the population, the sex distribution, parentage and the breeding success of animals,” says Le Roex.
In future, this non-invasive method of rhino monitoring can be used to inform decisions made in managing rhino populations. It will also help estimate the size of black rhino populations within SANParks and allow for individual animal identification using genetic data.
Black rhino within SANParks typically occur in small, isolated populations that were founded with just a few individuals. Building a DNA database can assist with decisions surrounding translocations of animals between parks – a process that can increase the genetic health of a population and prevent inbreeding.
Populations with reduced genetic diversity may be more susceptible to new pressures such as disease or drought, according to Le Roex. “These effects may be masked for a few generations, but over time these effects can have a significant impact on both short and long-term population survival.”
The creation of a rhino DNA database will assist with managing SANParks’ remaining black rhino populations – a crucial step in assisting an already vulnerable species, says Le Roex. “In short, we are doing our part to help with the long-term survival of black rhino in South Africa.”
Written by Taryn Arnott van Jaarsveld– SANParks Times Editor
Pictures: Cathy Withers-Clarke
Content courtesy of SANParks Times: www.sanparkstimes.co.za