Abstract:

The occurrence of certain rare plant species in specific ecological habitats is intricately linked to a myriad of environmental conditions, encompassing both biotic and abiotic factors. The prioritisation of monitoring efforts becomes more impactful when conservationists possess a comprehensive understanding of the ecology and distribution of rare species within their designated habitats and across the entire range of the species. In September 2023, a study was conducted in Jigme Dorji National Park to assess the ecology, distribution and threats to the critically endangered Bhutan poppy. This survey, employing random sampling, covered approximately 87 ha across Tshophu, Tshophu base and Jichudrakey base in Soe Gewog and analysed 202 2 × 2m plots. The survey revealed 57 plant species from 24 families, with Asteraceae (17.5%) and Papaveraceae (12.3%) dominating. Notably, 46% of families comprised a single species, and significant species richness differences were observed between Tshophu, Tshophu base and Jichudrakey base. Correlations between species richness and environmental variables, including slope, rock cover (%), bare soil cover (%) and herb cover (%), were identified as significant. The Bhutan poppy was positively and significantly associated with the southwest aspect, occupying 59% of surveyed plots. Species distribution modelling predicted a distribution area of approximately 37.29 square kilometres within the national park. However, future climate scenarios indicated a significant shift in the distribution of the Bhutan poppy. By 2041-2060, there is an anticipated decrease of 33% in its distribution area, with a shift towards the northeast. In the period from 2061 to 2080, the distribution is expected to increase by 8% from its current range, maintaining the northeast shift. The study identified three primary threats: grazing, trampling and harvesting, with livestock activities prevalent in 92% of plots and signs of harvesting in 45%. These findings provide crucial insights into the ecological dynamics, distribution patterns and potential conservation challenges facing the Bhutan poppy in Jigme Dorji National Park’s alpine habitats, emphasising the need for informed conservation strategies amidst changing environmental conditions.