- Proposed
- Under Assessment
- Preliminary Assessed
- Assessed
- VUPublished
Hygrophorus vernalis A.H. Sm.
- Scientific name
- Hygrophorus vernalis
- Author
- A.H. Sm.
- Common names
- IUCN Specialist Group
Mushroom, Bracket and Puffball- Kingdom
- Fungi
- Phylum
- Basidiomycota
- Class
- Agaricomycetes
- Order
- Agaricales
- Family
- Hygrophoraceae
- Assessment status
- Published
- Assessment date
- 2024-12-10
- IUCN Red List Category
- VU
- IUCN Red List Criteria
- A3c+4c
- Assessors
- Gregory Mueller (Chicago Botanic Garden / IUCN SSC Mushroom, Bracket and Puffball Specialist Group); Noah Siegel (25 Prospect Hill Road, Royalston, MA 01368, US / Global Fungus Assessment)
- Reviewers
- Anders Dahlberg (Swedish Species Information Centre, Uppsala / IUCN SSC Cup-fungus, Truffle and Ally Specialist Group)
Assessment Notes
Justification
Hygrophorus vernalis is a rare “snowbank” fungus forming ectomycorrhiza with conifers in high elevation forests in the Olympic, Cascade and Rocky Mountains in western North America. It produces fruitbodies in the spring and summer on the edges of melting snowbanks. Climate change is causing warmer and drier winters with elevated and lessened average snowfall which is causing a gradual, continued loss and deterioration of appropriate habitat for this species. An ongoing and future population decline of over 30% is suspected over three generations (50 years). The species is assessed as Vulnerable.Taxonomic notes
This species was d escribed by Smith (1941) from a collection made at Dear Lake, in Olympic National Park, Washington, USA.Geographic range
This species is confined to western North America and known from Washington and Idaho in USA and from British Columbia, Canada. Several observations from Mount Shasta in northern California have also been reported.Population and Trends
This snowpack fungus was described from the Olympic Peninsula in Washington. It is considered rare as it is currently known from nine sites in total: three from the Washington Cascade Range, one in eastern Washington, one in Idaho, one in British Columbia, Canada plus three observations from Mount Shasta in northern California (MyCoPortal 2024). It is confined to old growth high elevation conifer forests. While it is certainly over-looked within its restricted geographic distribution, the total number of sites is conservatively estimated to be fewer than 500 corresponding to fewer than 15,000 mature individuals, assuming c. 30 mature individuals per site.
Its habitat is being drastically affected by the changing climate, with warmer and drier winters that have elevated and lessened the average snowfall. Stoelinga et al. (2010) state that Cascade Range spring snowpack declined 23% during 1930-2007 while Fyfe et al. (2017) cite a 21.8% loss between 1982-1993 and 2000-2010; and models suggest that the rate of snowpack decline will increase substantially by the end of the century (Mote et al. 2005, 2018; Rhoades et al. 2018). As this species is restricted to snowbanks, an ongoing and future population decline of over 30% over three generations (50 years; Dahlberg and Mueller 2011) can be suspected.
Population Trend: Decreasing
Habitat and Ecology
Hygrophorus vernalis is an ectomycorrhizal fungus occurring in high elevation forest with Pinaceae, maybe also associating with hemlock. Fruiting occurs in late spring or early summer, when winter snowpacks melt. The fruitbodies occur scattered on melting snowbanks; often growing up through the snow, or on the immediate edge of banks. The ectomycorrhizal fungal mycelia is perennial and may live for several decades and potentially much longer with a continuous presence of living trees in appropriate habitats.Threats
Hygrophorus vernalis is a rare mycorrhizal snowbank fungus dependent on thick winter snowpacks to fruit. Snowbank fungi, unique to the western North American mountains, occur in areas with ample snowpack. They fruit in the spring and summer, as the snow melts and recedes. As the climate changes, warmer and drier winters have elevated and lessened the average snowfall. Climate change, continued loss of habitat, decline in area of old growth forests, and hotter, stand replacing fires are detrimental to this species.Snowpack decline in the western North American mountains has been well documented (Mote et al. 2005, 2018; Stoelinga et al. 2010; Zeng et al. 2018). Stoelinga et al. (2010) state that Cascade Range spring snowpack declined 23% during 1930-2007, and models suggest that the rate of snowpack decline with increase substantially by the end of the century (Rhoades et al. 2018).
