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Predicting the Potential Impacts of Trophy Hunting on Population Structure of Himalayan Ibex (Capra sibirica) in Northern Pakistan

Khan Muhammad Zafar, Begum Farida, Riaz Muhammad, Khan Babar, Karim Rehmat, Ali Karamat, Aman Safina

Polish Journal of Ecology

2019

Vol. 67, nr 3

264--270

We compared population structure and trophy hunting statistics of Himalayan ibex (Capra sibirica) in two community-controlled hunting areas (CCHAs) of northern Pakistan with varying duration of trophy hunting and isolated populations of C. sibirica. Based on fixed-point direct count method during winter 2016-2017, 939 ibexes were counted in Khyber and 346 in Hussaini, with a density of 7.5 and 3.2 animals km-2, respectively. Though the populations of C. sibirica at both the study sites have increased compared to the past estimates, we found variations in population structures and horn sizes, presumably as a result of trophy hunting. The sex ratios are skewed toward females in Khyber (87 males/100 females) and towards males in Hussaini (115 males/100 females). The trophy size males were 7% of the population in Khyber and 11% in Hussaini. Mean group (herd) size in Khyber was 28 (range = 1-117) and Hussaini was 20 (range = 1-79). Mean horn size of the trophies harvested in Khyber was 102 cm (± range = 91-114) compared to 108 cm (range = 99-121) in Hussaini. Stringent regulatory measures are suggested to determine the number of permits.

Effects of site conditions on sexual dimorphism and sex ratio in lowland populations of Aruncus sylvestris Kostel. (Rosaceae)

Marciniuk J., Marciniuk P., Rymuza K.

Polish Journal of Ecology

2010

Vol. 58, nr 2

249-257

Studies on sexual dimorphism in reference to vegetative features and on the sex ratio in different environmental conditions were carried out in lowland populations of dioecious species Aruncus sylvestris. It was shown that female individuals of Aruncus sylvestris produced higher flowering shoots, longer inflorescences, more leaves and longer and broader leaves than the male ones. All listed differences were statistically significant. In populations of Aruncus sylvestris growing in optimum ecological conditions (fertile and wet soil, half-light) the sex ratio M/F is close to 1:1. Changes of ecological conditions along the gradient of fertility, habitat moisture (estimated by the types of phytocoenoses) and intensity of solar radiation caused marked drift of sex structure towards the male domination. Light intensity was the crucial factor for the sex ratio in studied populations. Populations growing in half-light showed sex ratio M/F [is approximately equal to] 1:1 irrespective of habitat. Those growing in shade and in full light showed significant shift to male dominance. The largest deviation from 1:1 sex ratio (M/F [is approximately equal to] 1.0:0.2) was observed in extremely unfavorable habitat conditions (full sun irradiance, dry soil, strong competition from Elymus repens (L.) Gould). Obtained results demonstrated that female individuals of Aruncus sylvestris had markedly higher habitat requirements compared with the male ones.