A Southern Pacific Rattlesnake (Crotalus oreganus helleri) at Upper Las Virgenes Canyon Open Space Preserve (formerly Ahmanson Ranch).

The problem with rattlesnakes is that they can be notoriously difficult to see — especially when they are lurking in the shade on a narrow section of brushy trail and you’re wearing sunglasses.

Related post: Big Southern Pacific Rattlesnake at Ahmanson Ranch