Colors can be useful in identifying a venomous snake. Many poisonous snakes are brightly colored. This is one of those facts that’s true for many types of animals including frogs and insects. Brightly colored scales are a warning to predators that a reptile is poisonous.
A triangular head is a sign a snake is venomous. Compare the size of its head with its neck and you’ll see a notable difference in width. The copperhead is a great example of one with a triangular head.
Looking at a snake’s eyes in its triangular head can help in the identification process. A snake with slit-like, vertical pupils is likely to be venomous. Pit vipers are venomous and have eyes with vertical pupils.