Peltigera aquatica (Common name: Western Water Fan) is endemic to mountainous regions of western North America where it is restricted to aquatic habitats in high quality mountain streams. It is endangered by multiple factors including habitat destruction/degradation and climate change.
Peltigera aquatica is endemic to mountainous regions of the western United States, ranging from California north to Washington.
Demographic studies are needed to assess and monitor populations sizes. Many populations are known only from historical occurrences and there has been documented declines of some populations in long-term observational studies in California.
Population Trend: Decreasing
This species is restricted to slow moving, relatively small, cold mountain streams with high water quality and low turbidity.
The threats to this aquatic species are diverse. The major threats stem from 1) changes in habitat (macro- and micro- scales) resulting from deposition of pollutants and ecosystem alterations, 2) changes in habitat (macro- and micro- scales) that are likely to result from climate change, 3) changes in habitat (macro- and micro- scales) resulting from conversion and deterioration of natural habitats both historically and ongoing.
There are many conservation actions that can be taken including educating and training land managers and local botanists to identify the species so we can monitor its health, federally listing the species as endangered in the United States, improving numerous regulations and policies that would safeguard the aquatic habitats where the species occurs, and providing increased protection for buffer forest stands along riparian areas where the species occurs and could occur in the future.
The overall distribution of this species is well understood. Further research that will aid in the conservation of this species includes population assessments and monitoring, population genetics studies, and ecological studies that incorporate threats to the species. Additionally, a species recovery plan needs to be written.
Miadlikowska, J./ D. Richardson/ N. Magain/ B. Ball/ F. Anderson/ R. Cameron/ J. C. Lendemer/ C. Truong/ F. Lutzoni 2014: Phylogenetic placement, species delimitation, and cyanobiont identity of endangered aquatic peltigera species (lichen-forming Ascomycota, Lecanoromycetes). . - American journal of botany 101(7): 1141-1156.