Agkistrodon contortrix
Silhouette: Steven Traver · PhyloPic
In 3 days ~70% in a week ~90%
The eastern copperhead (Agkistrodon contortrix), also known simply as the copperhead, is a widespread species of venomous snake, a pit viper, endemic to eastern United States of America; it is a member of the subfamily Crotalinae in the family Viperidae.
The eastern copperhead has distinctive, dark brown, hourglass-shaped markings, overlaid on a light reddish brown or brown/gray background. The body type is heavy, rather than slender. Neonates are born with green or yellow tail tips, which progress to a darker brown or black within one year. Adults grow to a typical length (including tail) of 50–95 cm (20–37 in).
In most of the United States of America, the eastern copperhead favors deciduous forest and mixed woodlands. It may occupy rock outcroppings and ledges, but is also found in low-lying, swampy regions. During the winter, it hibernates in dens or limestone crevices, often together with timber rattlesnakes and black rat snakes. The eastern copperhead is known to feed on a wide variety of prey, including invertebrates (primarily arthropods) and vertebrates. Like most pit vipers, the eastern copperhead is generally an ambush predator; it takes up a promising position and waits for suitable prey to arrive.
As a common species within its range, it may be encountered by humans. Unlike other viperids, it often "freezes" instead of slithering away and fleeing, due to its habit of relying on excellent camouflage. Bites occur due to people unknowingly stepping on or near them. Copperhead bites account for half of the treated snake bites in the United States.
Five subspecies have been recognized in the past, but recent genetic analysis has yielded new species information. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Shenandoah National Park | 🇺🇸 United States | |
| 2 | Congaree National Park | 🇺🇸 United States | |
| 3 | Great Smoky Mountains National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Dallas | 🇺🇸 United States | |
| 2 | Washington | 🇺🇸 United States | |
| 3 | Houston | 🇺🇸 United States |
Possible
About 30% of wildlife watchers report an Eastern Copperhead sighting in Great Smoky Mountains National Park on a given day, based on 180 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 8th most-seen of the 27 reptiles we can rate there. Over three days the chance rises to about 70%, and over a week to about 90%, if each day is a fresh chance.
July
In that month about 50% of wildlife watchers report an Eastern Copperhead in Great Smoky Mountains National Park on a given day, against under 5% in November to February, the lowest months.
Between 7 and 10 pm
Across all the parks we cover, that three-hour window holds the most Eastern Copperhead sightings with a recorded time, and about 6 in 10 of them come between 6 am and 6 pm: it is seen both by day and at night.
3rd of 3
Of the 3 parks where we can rate Eastern Copperhead sightings, Great Smoky Mountains National Park ranks 3rd at about 30%. The best odds are in Shenandoah National Park (United States, about 40%) and Congaree National Park (United States, about 30%).
GBIF citizen-science records
It is estimated from how often the Eastern Copperhead is recorded against all the reptiles logged in Great Smoky Mountains National Park (180 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.
