More than 4' long and 14-15 rattles.
They don't come much bigger than this in Griffith Park:
In 2009, this grandmomma rattlesnake, looking very pregnant, scared quite a few visitors around Amir's Garden for a couple months. At the time, Park Rangers were patrolling for her so that they could relocate her safely to a less-traveled part of the park.
But Grandmomma suddenly dropped off the map. No sightings! As the garden caretaker, I seriously had eyes peeled for this gal. When she disappeared, I was worried something or someone had gotten to this beautiful creature before she could be safely moved. That said, rattlesnakes are territorial, and big ones maintain big territories. She could be anywhere in her territory.
Meanwhile, as we wondered where she might be, this photo kind of went viral throughout the park community. People kept asking me if I'd seen the big snake they saw in their email. I had to say 'no'.
At the end of August this year, Grandmomma suddenly reappeared in Amir's Garden. Terrified calls from garden visitors again went to the Park Rangers and this time they got up to the location just as she was leaving the area. They carefully placed her in a travel container and moved her to her new home in the park.
Here is Grandmomma circa early September 2011 - 15+ rattles strong but not so pregnant, cruising into her new low-density home where she won't terrify too many humans. What a gorgeous girl!