Answer: rattlers

AnswerCrossword Clue
RATTLERSDiamondback and sidewinder
rattlersRATTLER, one that rattles (to make a quick succession of short, sharp sounds)
rattlersA rattlesnake
RATTLERSBusy babies
RATTLERSSome snakes
RATTLERSDangerous snakes
RATTLERSOnes that warn before they attack
RATTLERSDangerous varmints
RATTLERSVibrating vipers
RATTLERSFreight trains
RATTLERSDesert menaces
RATTLERSSnakes
RATTLERSSnakes.
RATTLERSFast freights: Slang.
RATTLERSCertain reptiles.
RATTLERSTail-wagging animals
RATTLERSDiamondbacks
RATTLERSOater menaces
RATTLERSNoisy snakes
RATTLERSDesert dangers