The African wild dog (Lycaon pictus) is one of Africa’s most endangered species, with
fewer than 5,000 individuals surviving in the wild. Most of the remaining populations
are increasingly fragmented and small, making loss of genetic diversity, reduced gene
flow and inbreeding depression major concerns for the species. Recent efforts to
conserve and increase severely declined numbers of wild dogs in South Africa have been
focused on reintroductions to small protected areas to form a large metapopulation. The
subpopulation in KwaZulu-Natal (KZN) was the first created and is currently the second
largest population in the country with approximately 114 individuals. The overall goal for wild dog conservation in KZN is to establish a large, self-sustaining population within
the province. This study evaluated the genetics and behaviour of the wild dogs in the
province and explored how these factors influence long-term population health. An
assessment of the progress made through reintroduction efforts to date was conducted by
examining the current genetic diversity of the population and the pack and population
dynamics shaping it. These findings were also used to investigate strategies for
advancing the population to viable levels in the future.
The scope of the project was divided into five topics to address the most crucial
and intriguing aspects of African wild dog biology, conservation and management. First,
non-invasive faecal genetic techniques were refined for field sampling of wild dogs in
order to accurately genotype individuals and assess population heterozygosity. Second,
the influences of inbreeding and genetic heterozygosity on fitness traits were investigated
to determine if effects of inbreeding depression were apparent in the current population.
Third, reproductive sharing among dominant and subordinate wild dogs was evaluated
using genetic parentage analyses and long-term behavioural and demographic data.
Fourth, the extent of inbreeding avoidance in wild dog reproduction was examined and
the impact of this behaviour on future population persistence explored. Lastly, a
population viability assessment using genetic inputs and goals was conducted for the
current KZN wild dog population and strategies for the establishment of a viable future
population were suggested.
Genotyping and sampling errors were identified as significant sources of error in
non-invasive analyses using faecal samples from wild dogs. Software assessments and
replications were used to detect and correct genotyping errors. Sampling errors occurring in the field were corrected by evaluating multiple faecal samples from individual wild
dogs, comparing matching individual blood and faecal genotypes, and using a large
number of microsatellite loci to the identification of unique individuals in the dataset.
Results showed that although genotyping and sampling errors were significant in our
faecal DNA investigation of wild dogs, it is possible to correct these errors to generate
consistent and accurate genotypes. Whenever possible, future genetic studies on African
wild dogs and other endangered carnivores should apply these non-invasive techniques as
they avoid handling of these stress-sensitive animals and have proven to be a reliable
method of attaining good quality DNA.
Though some cases of incest have been observed in the KZN wild dog population,
the deleterious effects of inbreeding depression have only moderately begun to show on
the lifespans of inbred individuals. Compared to non-inbred individuals, inbred wild
dogs (f ≥ 0.25) had significantly shorter lifespans. However, this trend was limited to a
small number of packs, indicating that although this seems to be evidence of inbreeding
depression, a larger sample size is needed to confirm this. These results provide baseline
data on the genetic diversity and fitness of the population and highlight the importance of
tracking these characteristics in the future to ensure a healthy population.
Within the parentage analyses, a substantial portion of reproductive sharing
between dominants and subordinates was discovered in packs that contained siblings of
the alpha pair. Alpha females mated annually, whereas subordinate betas bred in over
half of all breeding years. Regardless of the number of adult males in the pack, litters of
mixed paternity occurred in over 50% of years. Alpha males sired just over half of pups
while one or two subordinate males sired the remaining pups in each pack. A skewed adult sex-ratio and frequent alpha mortalities for females and behavioural aggression in
males allowed most individuals to attain dominant status in their lifetime. These findings
suggest that more individuals than expected were able to contribute to reproduction in the
population. In addition, reproductive partitioning in wild dogs is mediated through a
combination of demographic, behavioural and hormonal factors.
Extensive behavioural and genetic data confirm that wild dogs largely avoid
mating with kin and suggest that avoidance is based on familiarity since only one
inbreeding pair had prior association with each other. Computer-simulated populations
revealed that preventing relatives from breeding could cause demographic declines and
extinction due to an absence of unrelated mates. Although stronger inbreeding avoidance
maintained significantly more genetic variation, small, isolated wild dog populations
could encounter potentially severe demographic impacts of these behavioural