Demographic structure and reproductive success of Primula allionii, a plant endemic to Maritime Alps

Primula allionii is a primrose endemic to the Maritime Alps. In order to evaluate its conservation status, we investigated its demographic structure and reproductive success. We studied the plant in three different plots in Roya Valley (France), representing the different structure of cliffs where the plant usually lives. The mean dimensional attributes and the environmental characteristics of areas where plant occurred were evaluated and different size categories were defined. Plant occurrence appeared non-random, with relatively high density of individuals. We recorded a high rate of seed production and a low morph bias. However, the population remains in a demographic equilibrium and very few seedlings were recorded in the population. The habitat in which the plant lives does not allow a substantial population renewal because of its extreme ecological features (vertical cliff, low soil availability, etc). Although the species is not currently threatened, its slow renovation dynamics, together with the fragmentation of the existing populations, could expose a population to stochastic extinction or sudden declines. Future conservation strategies should aim to facilitate recovery if any such event would occur.