Salvadora grahamiae
Silhouette: Alex Slavenko · PhyloPic
In 3 days ~20% in a week ~40%
Salvadora grahamiae, also known commonly as the eastern patch-nosed snake and the mountain patchnose snake, is a species of snake in the family Colubridae. The species is native to the southwestern United States and adjacent northeastern Mexico.
The specific name, grahamiae, is in honor of Colonel James Duncan Graham, United States Army Corps of Topographical Engineers. S. grahamiae is found in the US states of Arizona, New Mexico, and Texas, and in the Mexican states of Chihuahua, Coahuila, Querétaro, Tamaulipas, and Veracruz.
S. grahamiae occurs in a wide variety of habitats including forest, savanna, shrubland, grassland, and desert, at altitudes from sea level to 1,980 m (6,500 ft). S. grahamiae may attain a total length (including tail) of 47 in (120 cm). It has eight upper labials. The posterior chin shields touch or are separated by only one small scale.
S. grahamiae preys predominately upon lizards, especially those of the genus Aspidoscelis. It also eats reptile eggs, small snakes, nestling birds, and small mammals. S. grahamiae is oviparous. Eggs are laid in April–June, and... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Guadalupe Mountains National Park | 🇺🇸 United States | |
| 2 | Big Bend National Park | 🇺🇸 United States | |
| 3 | Saguaro National Park | 🇺🇸 United States |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Phoenix Zoo | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report an Eastern Patch-nosed Snake sighting in Big Bend National Park on a given day, based on 9 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 41st most-seen of the 48 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.
September
In that month about 30% of wildlife watchers report an Eastern Patch-nosed Snake in Big Bend National Park on a given day, against under 5% in July–August, October and December–February, the lowest months. That is one of Big Bend National Park's wettest months, with about 50 mm of rain against 10 mm in April.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Eastern Patch-nosed Snake sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
2nd of 3
Of the 3 parks where we can rate Eastern Patch-nosed Snake sightings, Big Bend National Park ranks 2nd at about 10%. The best odds are in Guadalupe Mountains National Park (United States, about 20%).
GBIF citizen-science records
It is estimated from how often the Eastern Patch-nosed Snake is recorded against all the reptiles logged in Big Bend National Park (9 verified sightings from 2019 to 2026), 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.
