Determining Optimal Stock Density of Punjab Urial (Ovis vignei punjabiensis) in Captivity for Breeding, Population Growth and Reintroduction Potential.

Abstract

The Punjab urial (Ovis vignei punjabiensis) is an endangered wild sheep of Pakistan, raised in captivity with the aim of re-introduction. To date, no information is available about population trends of this species in captivity. The current study was conducted with the aim to evaluate the population trend to better guide captive breeding for improved productivity and conservation value. Annual population data recorded and maintained by the Wildlife Department Khyber Pakhtunkhwa, Pakistan, were used. The data were compiled and analyzed in Microsoft Excel 2010 for determining growth rates and package Growthcurver in R-version 3.5.1 was used to produce a graphical representation of the population trend. The overall average annual population growth rate was rN = 0.22. Results revealed a fast initial growth rate with an average value of rN = 0.4 per year. Birth rates of bN = 0.45 for the first nine years were considerably higher than the death rates dN = 0.22 and the population increased with exponential growth. In the subsequent year, very high mortalities rates (dN = 1.2), likely attributed to the clumping of the population, resulted in the collapse of the population, leaving it in a state of unstable equilibrium. Results support the evaluation of management data to reveal carrying capacity in captive populations, to guide and inform appropriate release of surplus animals into natural habitats.