Population viability analysis and conservation of Chinese Grouse Bonasa sewerzowi in Lianhuashan Nature Reserve, north-west China

摘要

Chinese Grouse Bonasa sewerzowi is threatened by human activity, especially during the breeding season, in the Lianhuashan Mountains, Gansu Province, north-western China. We conducted a series of simulations on the viability of this population using the computer program VORTEX. The simulations suggested that the population had an extinction probability of 17% in 100 years using data gathered from current field work. Sensitivity analysis revealed that the predicted population trend was most sensitive to chick mortality, offspring per female per year, and adult male mortality. The first two parameters are correlated with human activity such as nest loss due to egg collecting by local people. When we set initial population size to the same size as carrying capacity, 2,500 individuals would constitute a minimum viable population (MVP). This would require a forest area of about 3,780 ha, which is smaller than the size of the Lianhuashan reserve, but the current population does not constitute an MVP due to the small initial population size. Furthermore, we found that if chick mortality declined by 5% or the number of offspring produced per female increased by 5% (i.e. reducing nest loss) under the current situation, local reserve size and current population would constitute an MVP. Therefore, the most practical and simple conservation management tool would be to increase the breeding success of Chinese Grouse, especially by limiting human activity during the incubation period.