UPDATE ON DEMOGRAPHIC AND GENETIC PARAMETERS OF A CAPTIVE POPULATION OF THREATENED SAHARAWI DORCAS GAZELLE (Gazella dorcas neglecta)

Trabajo Fin de Master en Medicina Veterinaria, Universidad de Lisboa

Between 1970 and 1975, 72 (36♂.36♀) Saharawi dorcas gazelles (Gazella dorcas neglecta) arrived in Finca Experimental la Hoya, Almería, southeast Spain. They were the founding individuals of a captive breeding programme, now managed as an European Endangered species Programme, currently with 236 (104.132) living individuals distributed among 12 institutions. Previous demographic and genetic assessment of this population was published in 2002 (Abáigar, 2002). An updated analysis was commended, ultimately motivated by the recent establishment of in situ reintroductions in Senegal. Besides the inclusion of the last 14 years of studbook data, this is the first thorough study to use the software programmes Population Modelling, ENDOG and SplitsTree4 for this taxon. The census history shows an overall increasing population, consistent with the incorporation of more institutions in the programme, although a tendency towards a stationary population is observed since 2010. Such tendency is corroborated by the current demographic parameters of annual growth rate (1.058), instantaneous rate of change (0.056) and net reproductive rate (1.283). Age-specific life table parameters show higher mortality rate, fecundity rate and reproductive value in males in almost all age-classes in contrast with higher survival rate and life expectancy in females. Sex and age structure of the global living population is close to pyramidal shape, as would occur in demographically stable populations. Plotting of annual gene diversity and mean inbreeding coefficient shows a positive impact of the incorporation of eight wild-caught individuals in the programme in the 90s. Current genetic parameters are the result of proper reproductive management of threatened species, and are in accordance with standardised targets when planning cooperative metapopulation breeding.

Peer reviewed