In situ and ex situ conservation of the endangered plant species Artemisia laciniata (Asteraceae) in Austria

Abstract

The aims of the present project were to reinforce the existing population of Artemisia laciniata (Asteraceae) in Austria’s Neusiedler See – Seewinkel National Park (NP) and to implement ex situ conservation measures to support this effort. The plants growing in the slightly saline meadows of the NP represent the last remaining population of this critically endangered species in Europe. In 2015, only 11 individuals were known to exist. Monitoring of the wild population was conducted, and early observations identified the mowing regime as a critical factor for the species’ survival. The mowing management was optimised based on the artificial mowing experiments performed in garden beds at the University of Vienna. The results showed that cutting the plants back to 80 mm in mid-June could lead to about 25 % reduction in the number of plants developing generative stems and a 75 % decrease in the number of generative stems compared to the control group. The attempt to activate the soil seed bank in an extinct field site was unsuccessful. However, sowing achenes and planting pot plants proved to be effective reinforcement measures. The survival rate of plantings reached up to 95 % after five years, and seedlings from achenes had a 20 % survival rate. However, the success was highly dependent on the location and its microhabitat. By 2023 the Artemisia laciniata population has been stabilised with more than 270 plants on site, and achenes collected over three years are stored at the Millennium Seed Bank. While reintroduction protocols are now in place and the measures appear promising, it is important to continue monitoring to evaluate the long-term success of the plantings, particularly in light of global warming.