Timber rattlesnakes are medium-sized venomous pit vipers found in the eastern United States. Males typically weigh around 2 pounds and reach 100-115 cm in length, while females weigh up to 1.3 pounds and reach similar lengths. They are carnivorous, giving birth to live young numbering between 5-20 called baby rattles. Timber rattlesnakes protect themselves by shaking their rattlers and biting if threatened, and are endangered due to loss of habitat.