The viability of a plant “on the edge”: Glaucium flavum (Papaveraceae) in Norway

The prospects for persistence of Glaucium flavum in Norway were evaluated by integrating data concerning spatio-temporal distribution, plant growth and development, reproduction, dispersal, seed bank and genetic variability. The distribution of Glaucium flavum in the Oslo Fjord region is much more restricted now than before. Out of the formerly recorded 35 populations, only eight populations were present in 1998, all in the outer parts of the fjord. The species is a short-lived iteroparous perennial in Norway. This growth habit gives high reproductive output from fertile individuals. G. flavum is self-compatible and can easily reproduce even in small populations. The ability to disperse long distances on water is limited. The observed seed bank will therefore enhance survival. No variation in isoenzymes was observed neither within nor among the G. flavum populations in the Oslo Fjord region. The species should be considered Endangered in Norway, according to the criteria given by IUCN.