Assessment Notes

Justification

This species is currently only known from a small number of disjunct sites in the mountains of western USA, most of which are in California. While its distribution is large, the very small number of records, even in well sampled areas, suggest that is a rare species. Given its apparent rarity over a large geographic area it is tentatively estimated that it occurs in up to 100-200x the number of known sites or 900-1,800 sites with an estimated population size between 9,000-27,000 (with a best estimate of 10,000-15,000) mature individuals occurring in scattered subpopulations of 1,000-1,500 mature individuals. While it is not possible to infer precise population trends due to the small number of records, based on changes in habitat quality across its distribution range it is suspected that the population is undergoing some decline. Given the wide population estimate and need for further sampling to better document its abundance and distribution it is assessed as Near Threatened C2a(i) .

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Taxonomic notes

Bovista californica was described from a collection made at Hat Lake in Lassen National Park (Kreisel 1967). Jarvis (2014) noted that B. californica and the European B. limosa are very closely related, based on ITS phylogenetic data and suggested that they may be synonymous, while noting slight morphological differences. More work is needed to confirm that B. californica is a distinct species. It is considered as a distinct species for this assessment pending data from other DNA markers that may provide additional resolution.

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Geographic range

The species is endemic to western USA. It is only known from isolated subpopulations in the Sierra Nevada and San Bernardino Mountains of California, USA, plus single sites in Oregon, Idaho and Washington and Wyoming.

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Population and Trends

The species is currently only known from a small number of disjunct sites in the mountains of western USA, most of which are in California. While its distribution is large, the very small number of records, even in well sampled areas, suggest that is a rare species. Given its apparent rarity over a large geographic area it is tentatively estimated that it occurs in up to 100-200x the number of known localities or 900-1,800 sites. If there is an average of 10-15 mature individuals at each site the estimated population size rages between 9,000-27,000 (although the best estimate is 10,000-15,000 mature individuals) occurring in scattered subpopulations of c. 1,000-1,500 mature individuals. While it is not possible to infer precise population trends due to the small number of records, based on changes in habitat quality across its distribution range it is suspected that the population is undergoing some decline.

Population Trend: Decreasing

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Habitat and Ecology

Bovista californica is saprotrophic; growing in humus and rich or sandy soil, often on the shores of alpine lakes, riparian zones and seeps in meadows. It is has mostly been found in clusters or groups, rarely solitary, and fruiting in summer and early fall.

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Threats

Trampling of lake shorelines near recreation areas is a probable source of habitat degradation for this species. Cattle grazing and hoof damage in and around meadows and seeps is also common and very likely to degrade suitable habitat.

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Conservation Actions

Cattle grazing should be limited and tourist access controlled in habitats where it is known to occur in order to reduce habitat declines. Targeted surveys for this species to better document its population size and habitat requirements are needed. Revisiting sites of historic collections is also needed. Taxonomic research with additional genetic markers is needed to determine the relationship between Bovista californica and European B. limosa.

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Use and Trade

No use/trade is known.

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Source and Citation

Mueller, G.M. & Siegel, N. 2025. Bovista californica. The IUCN Red List of Threatened Species 2025: e.T217580554A217581564. Accessed on 23 November 2025.

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