Critically Endangered
Pacifastacus fortis
Pacifastacus fortis
Pacifastacus fortis (known as the Shasta crayfish or placid crayfish) is an endangered crayfish species endemic to Shasta County, California, where it is found and first described in 1914, only in isolated spots along the Pit River and Fall River Mills.
Range and habitat
Pacifastacus fortis (known as the Shasta crayfish or placid crayfish) is an endangered crayfish species endemic to Shasta County, California, where it is found and first described in 1914, only in isolated spots along the Pit River and Fall River Mills. The exact subpopulations for the Shasta crayfish were discovered in 2004 through a genetic study that determined three different genetic clusters: Crystal Lake, the Big Lake group (that includes Big Lake Springs, JeShe, Lava, and Spring Creeks), and Thousand Springs.
Pins are Wikidata “endemic to” fields. Orange dots, when present, are GBIF occurrence tiles — survey bias included.
Habits
P. Fortis is nocturnal and remain idle behind cover for the majority of the day.
In crisis
The Shasta crayfish was designated as a rare species by California law in 1980 and an endangered species in 1988 both by the State of California and by the Federal Government. Throughout numerous 5-year species reviews from 1988 to 2013, this endangered classification has not changed.
Pacifastacus fortis is Critically Endangered on this catalog because that is the IUCN category stored on Wikidata. Confirm the official criteria and any later count on iucnredlist.org.
Sources
Written for this catalog from the English Wikipedia article on Pacifastacus fortis, Wikidata item Q3888507. Family and order context is original field-guide writing about the group, not a copied assessment of this one species. Wikipedia text is CC BY-SA. Not an IUCN assessment. Counts, when quoted, can change — confirm them on the recovery programme and on iucnredlist.org.



