RIO GRANDE VALLEY, Texas (ValleyCentral) — It is a chilling sound like no other in nature. Nothing rivets your attention quite like the threatening rattle of an agitated Diamondback rattlesnake.

When a rattler buzzes you, it is a serious warning, “Don’t tread on me.” Failure to heed the alarm could result in serious injury or death.

A black forked tongue flicks ominously, as the imposing snake “tastes” the air. The tongue gathers scent particles and then retracts, delivering them to the Jacobson organ on the roof of the mouth.

Diamondbacks are pit vipers, and just beneath each eye are heat-sensitive receptors. These heat-sensing facial pits enable rattlers to locate their prey even in total darkness.

Diamondback rattlesnakes are the most common venomous snake in Texas, and if you spend enough time in the wildlands an occasional encounter is inevitable.

Approximately 7,000 people are bitten by venomous snakes annually in the United States, with some dozen resulting in death. On average, one or two people in Texas die each year from envenomation.

The majority of these encounters are avoidable as most result from people attempting to harass or handle the serpents. However, it is best to be on your guard when trekking thru the brush country of South Texas, as you don’t want to provoke a rattler into launching a defensive strike.

Experts agree that the best snakebite kit is your car key. The quicker you use it the better, with hopefully someone else driving, as only antivenom administered at the hospital emergency room can neutralize the rattler’s toxins.

The record length for a Western Diamondback rattlesnake is reported to have topped seven feet, but a true six-footer is somewhat of a rarity in deep South Texas.

The “cascabel” as it is known in Spanish is normally not aggressive and most want to avoid humans, but watch your step, as dry tail “slim” does not always provide a courtesy rattle.