Narcissus willkommii

This species is known from several subpopulations scattered along a 5 km stretch of river in the central region of Algarve. In 2018, the most recent census estimated the number of mature individuals at c. 1,426, based on observation of 13 sites and estimation in 12 sites, however, this number may be an underestimation of the population since the year was not favourable to early flowering species (A. Carapeto pers. comm. 2018).

In the past, other subpopulations were known in the region. However, the causes of disappearance in some sites are better known than in others. One of those lost subpopulations, where the species was reported to be very abundant, was completely destroyed by the construction of a road in the 1990s. Another subpopulation has not been reported since the 1970s. Between 2002 and 2010-12, the population seemed stable in numbers, although its habitat was still declining in quality due to Arundo donax expansion and other minor threats, particularly vegetation control in one part of the river bank. In 2018, population monitoring showed that at least three small groups of individuals disappeared due to the expansion of A. donax and river bank erosion. Over the last 45 years (equivalent to three generations), this species is estimated to have experienced a decline in more than 95% of its EOO, which is inferred to represent a population reduction of, at least, 50% (A. Carapeto pers. comm. 2018).