Can a Dead Stingray's Barb Still Be Lethal?

On Monday, Sept. 4, 2006, a tragic day for both humans and Dasyatidae, Steve "The Crocodile Hunter" Irwin was fatally injured while filming a documentary. While swimming above a large stingray of the Dasyatidae family off the coast of Queensland, Australia, the famed naturalist and TV personality died when the stingray's barbed tail flicked upward and pierced Irwin's chest multiple times. A barb from the tail broke off and became lodged in his heart.

Before Irwin’s unfortunate death, only two other fatalities from stingray stings had been reported off the coast of Australia [source: Peatling]. Irwin's death is especially heartbreaking because, despite their intimidating appearance, stingrays are generally peaceful creatures. They’re often referred to as the "pussycats of the sea" [source: Williamson].

The Dasyatidae family consists of around 70 species of stingrays, ranging in size from just under a foot to as large as 6.5 feet (30 centimeters to 2 meters) in diameter [source: McEachran and Carvahlo]. Stingrays typically reside in shallow coastal saltwater environments, though some species are also found in freshwater lakes and rivers in South America. These fish feed on mollusks, shellfish, and bivalves, using powerful grinding plates in their mouths to crush their prey’s shells. Stingrays use their deadly barbs solely for self-defense, not for hunting. Though typically gentle, the unexpected death of Steve Irwin demonstrated that their stingers can indeed be deadly.

It’s well-known that another potentially hazardous marine creature, the jellyfish (family Cyaneidae), can still pose a danger even after death. Its tentacles contain nematocysts (stingers) that deliver toxins used for defense and capturing prey. A dead jellyfish washed up on the shore can still cause pain if someone steps on it. Similarly, stingrays produce toxins through the barbs on their stingers. This leads to the question: Can a stingray's sting remain lethal after its death?

When Stingrays Strike!

To determine whether a dead stingray can still kill with its barb, we first need to understand how stingrays use their tails for defense.

Apart from its broad, flat, wing-like body, mouth, eyes, gill slits on its dorsal side, and its tail, a stingray is largely featureless. This helps the stingray in its natural habitat; it lies flat on the ocean floor and camouflages itself by blending with the sand. As stingrays often reside just off the shore, beachgoers can easily and unintentionally step on one that's hidden beneath the water's surface.

When stingrays are stepped on, handled roughly, or startled, their tails lash forward toward their heads like a scorpion’s or to the side. The end of a stingray’s tail (called its caudal appendage) contains its venomous apparatus. Long spines, several inches long and typically responsible for the "sting" in "stingray," rest in a grooved area in the tail known as the cuneiform area. These spines are hidden from view when the stingray feels unthreatened. However, the stingray is always ready for action; tiny barbs are embedded within the spine, constantly bathed in the stingray’s venom while resting beneath the spine’s surface inside the integumentary sheath.

When threatened, the stingray whips its tail, causing the barbs on the spines to tear through the delicate tissue of the integumentary sheath, and the spines extend at a nearly perpendicular angle to the tail. As the stingray moves, its tail becomes a whip-like weapon with a venomous barb protruding. The spines are rigid and, in some species, can even pierce bone [source: Lovgren]. However, they are also brittle and can break off, lodging in any wound they cause. The venom, contained in the mucus-like coating over the barb, is introduced into the body through the wound, a process known as envenomation.

It doesn’t sound like a pleasant experience, and indeed, it’s not. While it’s usually not life-threatening, it is certainly painful. Death from a stingray wound is possible, but what happens if the stingray is dead?

Can a Dead Stingray Still Kill You?

While it's possible to die from a wound caused by a dead stingray, it's highly unlikely. The tail movement is what causes the barbed spine to rise and tear through the integumentary sheath. In other words, there’s no muscle control over the spine or barbs; they become dangerous due to the tail's movement, much like how a folding knife springs open when flicked.

This means a dead stingray shouldn't be capable of inflicting the injury required to envenomate someone, unless it died in a defensive position. If the spine was already raised and ready to strike but hadn’t yet made contact when the stingray passed away, it could still pose a threat if someone handling the dead stingray punctured their skin with the spine.

Mytour couldn't find any reports of a person being killed by a dead stingray. However, there have been incidents where fishermen have died from encounters with dead or even frozen venomous fish. Even after death, the venom produced by the stingray while alive remains a danger to humans.

A person is far more likely to experience severe pain and possible complications from encountering a startled stingray than death. So what should you expect if you step on a stingray? First, prepare for intense pain. The wound caused by the barbed spine cutting through flesh can be excruciating by itself, but it’s the venom that truly heightens the pain at the site of the injury.

Stingray venom is a potent substance. In high enough doses, it can disrupt the electrical function of the heart, leading to either dilation or constriction of blood vessels [source: Williamson et al.]. However, in most cases, the venom doesn't reach the heart but stays around the wound, where it causes tissue necrosis, or cell death. To alleviate the pain, soaking the injury in very hot water has been found to provide some relief. Bacterial infections are common, so antibiotics may be needed if a stingray sting occurs. It's strongly advised that anyone stung by a stingray seek medical help, as the venom will continue to damage soft tissue without treatment and won't heal on its own.

In the end, it's wise to show respect to the 'pussycats of the sea.' Even the gentlest of pussycats will defend themselves when provoked.