Thamnophis cyrtopsis
Silhouette: Alex Slavenko · PhyloPic
In 3 days ~20% in a week ~40%
Common names: blackneck garter snake, black-neck garter snake Thamnophis cyrtopsis, the blackneck garter snake, is a species of garter snake of the genus Thamnophis. It is native to the southwestern United States, Mexico and Guatemala, and can be found in a wide range of different habitats, often near water sources.
There are three recognized subspecies of the blackneck garter snake, two of which, Thamnophis cyrtopsis cyrtopsis and Thamnophis cyrtopsis ocellatus, are described below. Thamnophis cyrtopsis cyrtopsis (Kennicott, 1860) The western blackneck garter snake may attain 107 cm (42 inches) in total length. The snake is colored dark olive with an orange-yellow stripe that is displayed on the middle of the body from the top while the underside is usually a cream or light shade of gray. The western blackneck is a water snake that lives near rivers, swims, and eats small fish and tadpoles.
Thamnophis cyrtopsis ocellatus (Cope, 1880) The eastern blackneck garter snake is smaller than the western blackneck garter snake, with an average total length of less than 51 cm (20 inches). It is frequently... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Saguaro National Park | 🇺🇸 United States | |
| 2 | Guadalupe Mountains National Park | 🇺🇸 United States | |
| 3 | Big Bend National Park | 🇺🇸 United States | |
| 4 | Cumbres de Monterrey National Park | 🇲🇽 Mexico |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Austin | 🇺🇸 United States |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Arizona-Sonora Desert Museum | 🇺🇸 United States | |
| 2 | ABQ BioPark Zoo | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Black-necked Gartersnake sighting in Austin on a given day, based on 67 verified sightings from GBIF citizen-science data. It is the 21st most-seen of the 37 reptiles we can rate there. Over three days the chance rises to about 20%, and over a week to about 40%, if each day is a fresh chance.
February, April and June–November
In those months about 10% of wildlife watchers report a Black-necked Gartersnake in Austin on a given day, against under 5% in March, May and December–January, the lowest months.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Black-necked Gartersnake sightings with a recorded time, and about 7 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Only Austin, in our data
Austin is the only city on Wallace's Line with enough records to rate Black-necked Gartersnake sightings: about 10% of wildlife watchers there report one on a given day.
Same genus: Thamnophis
The closest relatives of the Black-necked Gartersnake that you can see in Austin (genus Thamnophis, Garter Snakes) are Western Ribbon Snake (about 10%) and Checkered Garter Snake (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Black-necked Gartersnake is recorded against all the reptiles logged in Austin (67 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
