Snakes and spiders in Siskiyou County, California
Siskiyou County, home of Yreka, has 14 snake and 10 spider species on record, from 1,466 licensed snake and 197 spider records. Venomous species here: the western rattlesnake and the western black widow.
Are there venomous snakes or spiders in Siskiyou County?
Yes. The western rattlesnake: 32 licensed records, 1% of all California records of it. The western black widow: 2 licensed records, 0% of all California records of it.
What snakes are in Siskiyou County?
In all, 14 snake species are on the Siskiyou County list. The most recorded are the western terrestrial garter snake (735), the common garter snake (306) and the western aquatic garter snake (197).
| # | Species | Records | Share of California records |
|---|---|---|---|
| 1 | Western terrestrial garter snake Thamnophis elegans | 735 | 3% |
| 2 | Common garter snake Thamnophis sirtalis | 306 | 5% |
| 3 | Western aquatic garter snake Thamnophis couchii | 197 | 5% |
| 4 | Aquatic garter snake Thamnophis atratus | 82 | 2% |
| 5 | Western rattlesnake venomous Crotalus oreganus | 32 | 1% |
| 6 | Gopher snake Pituophis catenifer | 27 | 0% |
| 7 | California mountain kingsnake Lampropeltis zonata | 16 | 3% |
| 8 | Northern rubber boa Charina bottae | 15 | 2% |
| 9 | Eastern racer Coluber constrictor | 14 | 1% |
| 10 | Northwestern garter snake Thamnophis ordinoides | 9 | 4% |
| 11 | Striped whipsnake Masticophis taeniatus | 8 | 9% |
| 12 | California kingsnake Lampropeltis californiae | 5 | 0% |
| 13 | Ring-necked snake Diadophis punctatus | 5 | 0% |
| 14 | Sharp-tailed snake Contia tenuis | 5 | 1% |
When are snakes out in Siskiyou County?
Observation records of snakes in Siskiyou County run mostly April through September, peaking in July with 32% of them; across California the peak is May.
What spiders are in Siskiyou County?
In all, 10 spider species are on the Siskiyou County list. The most recorded are Hypochilus kastoni (40), the goldenrod crab spider (7) and the Johnson jumper (6). Siskiyou County holds more than half of all California records of Hypochilus kastoni.
| # | Species | Records | Share of California records |
|---|---|---|---|
| 1 | Hypochilus kastoni | 40 | 93% |
| 2 | Goldenrod crab spider Misumena vatia | 7 | 3% |
| 3 | Johnson jumper Phidippus johnsoni | 6 | 1% |
| 4 | Colonus hesperus | 4 | 1% |
| 5 | Koch's wolf spider Alopecosa kochi | 4 | 0% |
| 6 | California flattened jumping spider Platycryptus californicus | 3 | 3% |
| 7 | Western black widow venomous Latrodectus hesperus | 2 | 0% |
| 8 | Marbled cellar spider Holocnemus pluchei | 1 | 0% |
| 9 | Western lynx spider Oxyopes scalaris | 1 | 0% |
| 10 | Western parson spider Herpyllus propinquus | 1 | 1% |
When are spiders out in Siskiyou County?
Observation records of spiders in Siskiyou County run mostly April through September, peaking in August with 23% of them; across California the peak is April.
What stands out in Siskiyou County
Species for which Siskiyou County holds a large share of all California records: Hypochilus kastoni, 93% (40 of 43).
Common in California, not on the Siskiyou County list
Among the snakes most recorded across California, these do not reach the county list: the sidewinder (1,923 statewide), the two-striped garter snake (1,620 statewide), the western shovel-nosed snake (1,482 statewide) and the glossy snake (1,425 statewide). Few records here can mean the species is rare in the county, or that few people have looked.
Among the spiders most recorded across California, these do not reach the county list: the bold jumper (2,606 statewide), the half-edged wall jumping spider (2,178 statewide), Steatoda nobilis (1,914 statewide), the false black widow (1,201 statewide), the buttonhook leafbeetle jumping spider (825 statewide) and Habronattus pyrrithrix (800 statewide). Few records here can mean the species is rare in the county, or that few people have looked.
Harmless lookalikes in Siskiyou County
Rattlesnakes are on the county list, and so are harmless species often taken for them: the gopher snake. Coral snakes are not on the California list, but GBIF holds 3 coral snake records of any license in California (Sonoran coralsnake 3): treat any snake like this as venomous until identified. Harmless species often taken for them here: the California mountain kingsnake.
Siskiyou County among California counties
By licensed snake records Siskiyou County ranks 17th of 58 California counties with any.
Other California counties with their own page: San Diego County, Lassen County, Shasta County, Riverside County, San Bernardino County, Humboldt County, Sonoma County and San Mateo County.
The whole state: venomous species in California, all snakes, all spiders.
GBIF records read 2026-09-29. Listed: any license. Counted: CC0/CC BY only. How we count.