The Land Snails and Slugs of Great Basin National Park

Land snails and slugs live in woodland leaf litter and soil, boulder fields and talus slopes, streamside meadows and the plants around springs throughout the Great Basin. They matter to these mountain habitats: they break down dead plants so bacteria and fungi can use them, recycle nutrients such as calcium and nitrogen, carry fungal spores through the litter, and are a vital source of calcium and protein for the birds and mammals that eat them.

The survey

In 2016, Mark Ports, emeritus professor of biology at Great Basin College in Elko, Nevada, was in the last season of a three-year survey (2014–2016) of the park's land snails and slugs: which species live there, which habitats they prefer and how dense their populations are. By then 17 species of land snail and one slug had been recorded.

Where they live

The number of species at a site ranged from one, at 2,000 m in dry pinyon pine and Utah juniper woodland on Lower Lehman Creek, to nine, at 2,800 m in moist mixed aspen–conifer woodland on upper Strawberry Creek. Both sites sit on granitic schist, which offers snails little free calcium for their shells; snails in places like these have been shown to get calcium and nutrients from decaying leaves instead.

Where the bedrock is limestone or dolomite, there is free calcium. With a moist understorey of shrubs, such rock supports eight species below Grey Cliffs on Baker Creek and on the South Fork of Big Wash. The highest snails in the park live at about 3,200 m, at Stella Lake and in a nearby bristlecone pine woodland.

Most of these communities depend on moist woodland and shrubs, but some species are specialists:

• On limestone boulders and talus with shrub and grass cover: both mountainsnail species and the Montane Snaggletooth.
• In wet meadows and springs only: the Meadow Slug, the two amber snails and the Cross Vertigo.

The species and habitats found in the park resemble those of other high ranges of the eastern Great Basin: the Deep Creek Range to the north along the Utah border, the Ruby Mountains to the northwest in northeastern Nevada, and the Schell Creek Range west of the Snake Range.

Words on this page from people and organisations outside the federal government are paraphrased; rewritten in hubnx's own words.

Sources

• Mark Ports, biology professor (emeritus), Great Basin College, "Land Mollusks of Great Basin National Park," The Midden (Great Basin National Park), vol. 16, no. 1, summer 2016, National Park Service. https://www.nps.gov/articles/000/land-mollusks-of-great-basin-national-park.htm
• The article's photographs, supplied by the author, are not reproduced here.