For southern Africa’s wild dogs to survive, they must mingle. The importance of transboundary conservation areas has been highlighted again recently when research showed that isolated wild dog populations could be detrimental to the future of this endangered species.
According to a research project by the University of Johannesburg (UJ) in collaboration with the Endangered Wildlife Trust (EWT), the wild dogs in the Kruger National Park (KNP) are genetically different than those in the Lowveld of Zimbabwe. This is a sign that natural dispersal between these populations is limited and highlights the importance of connecting protected areas.
The project team looked at whether the Greater Limpopo Transfrontier Conservation Area (GLTFCA) successfully connects the KNP populations with those in Zimbabwe’s Gonarezhou National Park. The GLTFCA includes the KNP, Limpopo National Park in Mozambique, Gonarezhou, the Manjinji Pan Sanctuary and Malipati Safari Area in Zimbabwe. Together, they host about a tenth of the global wild dog population.
“Zimbabwe is one of the few places where wild dogs still roam freely,” says UJ animal genetics PhD student Laura Tensen. If the dogs dispersed naturally between these areas, expensive translocations could be avoided in the future and also encourage population growth. If dispersal between the protected areas does not occur, this could result in problems for the Kruger and Gonarezhou wild dogs.
One of the major problems associated with low genetic variety in areas where dispersal does not take place is inbreeding. “The diversity in isolated populations will decrease quickly and that will impact breeding success,” says Tensen. Inbred dogs also face a greater challenge adapting to changing environmental conditions such as droughts and diseases. “Effectively, the population size will decrease further if the wild dogs are unable to disperse.”
While limited dispersal does take place, it is not enough. “For now the genetic diversity is enough to avoid severe inbreeding, but over about 10 generations there won’t be much diversity left.”
In theory, the solution should be easy. “Immediate strategies should focus on increasing the quality of habitat corridors between reserves in the GLTFCA,” explains Tensen. In addition higher wild dog survival rates must be secured in unprotected areas, she says. Dr Kelly Marnewick, Carnivore Conservation Programme manager for the EWT confirms this. “There is a lack of safe habitat for them to exist so there are just over 450 animals in South Africa. They get shot, snared and are vulnerable to diseases carried by unvaccinated domestic dogs.”
Tensen’s project will now be expanded to look at the dispersal between wild dogs in Zimbabwe and Mozambique, but says that this research alone is not enough to sound warning bells, as one needs to look at the entire picture. Combined with information such as life history, pup survival rate, causes of death and litter sizes, one can get a better understanding of the current situation.
Written by René de Klerk – SANParks Times Reporter
Pictures: Laura Tensen
Content courtesy of SANParks Times: www.sanparkstimes.co.za