The Asiatic wild ass (Equus hemionus) is a mammal species forming in a unique mating system. In Israel it is mostly distributed in the Negev Highlands. Forming in territorial polygyny, males establish territories near water and food sources to access females. Hence, water source distribution carries a significant role for the species' courtship and reproductive success. Due to limited distribution of natural water sources, the limited breeding opportunities for males affects the overall populations' genetic diversity. The main objective of my master's and PhD study is to evaluate the behavioral and genetic effects of the water source interface on genetic diversity in small populations with a tendency to strong polygyny. The results of the research in turn will make it possible to examine in the long term the resistance of the species in response to this change and accordingly to recommend and implement the approach as a conservation tool. The specific research goals are: 1. Examining the relationship between genetic kinship and social relations among females in the population and how these impacts the utilization of resources and reproductive success; 2. Examining the geographic characteristics that contribute to the reproductive success of territorial males; 3. Examining the tendency of inbreeding avoidance among breeding individuals over 5 years of research in response to a change in the water source distribution; 4. Examining the effective size of the population and heterozygosity (indirect measures of genetic diversity) following the change in the distribution of water sources. This empirical study combines ecological behavior research and nature conservation genetics, utilizing direct observations to study territorial and social behavior. The genetic aspect involves non-invasive DNA extraction from dung samples, followed by sequencing at unique single nucleotide polymorphism sites. Parentage tests, genetic relatedness assessments, and the examination of social-genetic relationships are conducted, contributing to ongoing genetic monitoring since 2020. We discovered from 864 fecal samples collected that, following the water source management conducted by the INPA in 2020 to increase and relocate the water sources in the Negev Highlands, the proportion of mating males out of all adult males in the population had increased from an estimated 16%-19% to 43%-48%, and also the increase in proportion of new breeding males was significant (from 31.2% in 2019 to 78.3% in 2020 (Z= - 2.87, p-value=0. 002)). This discovery was possible following a SNP error rate estimation and filtration method we developed for next-generation sequencing genotype datasets, that allowed us to reduce our genotype data from 0.34% error rate to 0.17%. During the summers of 2022 and 2023, 967 fecal samples were analyzed by Next-Generation sequencing, among them 433 samples of adult males, 341 of adult females, and 193 samples of juveniles. The results will soon be processed to examine the connection between the genetic and the social relationships of females that were observed and sampled in female groups during 2020-2023.
