Eastern Black-tailed Rattlesnake
Crotalus ornatus
Silhouette: Bill Bouton (source photo) & T. Michael Keesey (vectorization) · PhyloPic
- KingdomAnimalia (Animals)
- PhylumChordata (Chordates)
- ClassSquamata
- FamilyViperidae (Vipers)
- GenusCrotalus (Rattlesnakes)
- SpeciesCrotalus ornatus (Eastern Black-tailed Rattlesnake)
About the Eastern Black-tailed Rattlesnake
The black-tailed rattlesnake (Crotalus molossus) is a venomous pit viper species found in the southwestern United States and Mexico. Four subspecies are currently recognized, including the nominate subspecies described here.
A 2012 revision showed that eastern populations from Texas and central and eastern New Mexico form a distinct species separate from C. molossus: Crotalus ornatus Hallowell 1854. Alternate common names are green rattler, and Northern black-tailed rattlesnake.
This medium-sized species averages from 76 to 107 cm (30 to 42 in) in length. Large specimens are usually not much more than 100 cm (39 in) long, although lengths of 125.0 cm (49.2 in) (Gloyd, 1940), 125.7 cm (49.5 in) (Klauber, 1972), and 129.5 cm (51.0 in) (Shaw & Campbell, 1974) have been reported. The females tend to be larger than the males.
They range in color from yellows and olive greens to browns and black. As their name implies, one of their most distinguishing features is, despite variations in body color, entirely black tail scales. Often, this rattlesnake has a black band across its eyes extending diagonally down to the corners of its mouth... Wikipedia →
Recent sightings of Eastern Black-tailed Rattlesnake in Big Bend National Park
LIVEiNaturalistClosest Relatives at Big Bend National Park
Global Distribution
Warmer areas are where this animal is recorded most often.
Parks Where Found
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Big Bend National Park | 🇺🇸 United States | |
| 2 | Guadalupe Mountains National Park | 🇺🇸 United States |
Quick answers
What are the chances of seeing a Eastern Black-tailed Rattlesnake in Big Bend National Park?
About 30% of wildlife watchers report a Eastern Black-tailed Rattlesnake sighting in Big Bend National Park, based on 143 verified sightings from GBIF citizen-science data.
When is the best time to see Eastern Black-tailed Rattlesnake in Big Bend National Park?
August has the highest sighting rate for Eastern Black-tailed Rattlesnake in Big Bend National Park in our monthly data.