Black-necked Gartersnake
Thamnophis cyrtopsis
- KingdomAnimalia (Animals)
- PhylumChordata (Cordats)
- ClassSquamata
- FamilyColubridae (Colúbrids)
- GenusThamnophis (Garter Snakes)
- SpeciesThamnophis cyrtopsis (Black-necked Gartersnake)
Closest Relatives at Big Bend National Park
Checkered Garter Snake
Thamnophis marcianus
Trans-pecos Ratsnake
Bogertophis subocularis
Chihuahuan Nightsnake
Hypsiglena jani
Coachwhip
Masticophis flagellum
Long-nosed Snake
Rhinocheilus lecontei
Gopher Snake
Pituophis catenifer
Great Plains Ground Snake
Sonora episcopa
Big Bend Patchnose Snake
Salvadora deserticola
Baird's Ratsnake
Pantherophis bairdi
Plain-bellied Water Snake
Nerodia erythrogaster
Glossy Snake
Arizona elegans
Striped Whipsnake
Masticophis taeniatus
📅 Monthly Probability
☀️ When They're Spotted
Most active during daytime hours (6am–6pm) · across all parks (global)
Global Distribution
Where this species is recorded worldwide. Restricted to human observations from 2019 onwards — the same kind of record and the same period the probabilities on this page are built from, so collar-tracking studies, camera-trap arrays and museum specimens are excluded. Around Santa Rosa that removes 5,924 GPS fixes from a handful of tagged jaguars.
where this species is recorded (GBIF density — it tracks where observers go, not how likely a sighting is) · parks where it occurs — tap a pin for the sighting probability there
Parks Where Found
| # | Park | Country | Probability |
|---|---|---|---|
| 1 | Big Bend National Park | 🇺🇸 United States | |
| 2 | Cumbres de Monterrey National Park | 🇲🇽 Mexico | |
| 3 | Guadalupe Mountains National Park | 🇺🇸 United States | |
| 4 | Grand Canyon National Park | 🇺🇸 United States |
Quick answers
What are the chances of seeing a Black-necked Gartersnake in Big Bend National Park?
About 16% of visitor-days record a Black-necked Gartersnake sighting in Big Bend National Park, based on 37 observer-days of citizen-science data from GBIF.
When is the best time to see Black-necked Gartersnake in Big Bend National Park?
July has the highest sighting rate for Black-necked Gartersnake in Big Bend National Park in our monthly data.