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Stingrays are docile creatures found in almost every body of salt water in the world and even in a few major fresh water river systems. They rely on their venomous barbs locate along their whip-like tails for self defense. Most stings are not fatal. However, serious treatment should be taken if the wound is inflicted in the abdominal cavity. It is estimated that there are nearly two thousand human-stingray occurrences yearly in the United States alone. In comparison, 2010 recorded thirteen shark attacks along the coastal United States.

A stingray lying on the seabed.

Prevalence

Following are the number of recorded fatal attacks by different animals in North America in recorded history

Animal	Number of attacks
Mountain Lion	20
Black Bear	60
Brown Bear	65
Great White Shark	17
Bull Shark	9
Tiger Shark	27
Stingray	3

Following are the number of recorded attacks by different animals worldwide

Animal	Number of attacks
Mountain Lion	88
Black Bear	107
Brown Bear	93
Great White Shark	431
Bull Shark	139
Tiger Shark	169
Stingray	2000

Motivation

A stingray burying itself in the sand.

Against common belief, the stinging barb on a stingray is not used to catch prey. It is merely a defense mechanism against predators. Stingrays are extremely docile creatures; never attacking unless provoked or scared. Stingrays spend most of their time buried in sand with only their eyes above the ocean floor, waiting for potential prey to come into view. When disturbed, stingrays would rather swim away than attack. Most cases of stingray wounds are caused by victims stepping on the creature in shallow murky water. It then whips up its tail and jabs the barb into the victim’s flesh.

Biological structure of the barb

A stingray's barb (ruler in cm).

The barb is covered with rows of sharp flat spines, composed of vasodentin. Vasodentin is an incredibly strong cartilaginous material which can easily cut through flesh. The undersides of the spines contain two longitudinal grooves which run along the length of the spine and enclose venom-secreting cells. Both the venom-secreting tissues and vasodentin are enveloped in an epidermis that tears open when the barb is plunged into a victim. Some spines may break off as the barb exits the wound and stay within the victim causing prolonged envenoming.

Historical Uses of stingray barbs

Helen R. Haines, Phillip W. Willink, and David Maxwell observed Mayan iconographic images depicting self-sacrifice by stingray venom. Personal bloodletting was considered a sacred duty among the rulers at the time. It was believed that exsanguination opened a direct path between the natural and super-natural worlds. Many sacrificial beings may have been led to a state of visions and trances induced by the poison within stingray barbs.

Epidemiology

Many victims of stingray related injuries suffer from physical effects including nausea, vomiting, diarrhea, extreme pain at the wound, muscle cramps, and a laceration at the puncture sight. There have been cases of severe consequences which may include embedded spines, infection, hypotention (a slower heart rate), and even possible amputations or death. Stingray wounds have also been found to bleed profusely and for a long amount of time after the initial puncture. It has been suggested that there may be some sort of anti-hemoglobin agent incorporated with the secreted venom, but James H. Diaz, Professor at the School of Public Health has rebuked that theory .

Treatments

Treatment of a fresh stingray inflicted wound should not be taken lightly. Initial analysis should be taken right after the attack, followed up by professional care. Many authorities recommend immediate hot water immersion of the wound due to the heat liable quality of the venom. Bathing the wound in salt water has also been proven effective in disinfecting the wound. According to the Brazilian study by Katia C. Barbar the invasion of certain bacteria has been proven to help speed the process of healing in many individuals. If the barb is inserted in the abdominal cavity the victim should immediately be taken to emergency care. When the poison is injected within, or near, vital organs life may be at risk.

Prevention

Stingrays are gentle creatures, never fighting unless provoked. Since they tend to spend most of their time buried in sand, it is recommended to shuffle across the ocean floor. They would most likely swim away from a possible threat. Waders, snorkelers, and divers should always observe seafloors and never provoke a stingray. Most fatal interactions with stingrays occur with swimmers staying too close to the seabed and running into a scared stingray. If the stingray is swimming in open water, it is possible for its tail to whip around and catch a swimmer in the chest. If a stingray feels threatened, it will fling its tail around to keep anything and everything away from it. Many other stingray occurrences take place among fishing boats. Stingrays are often caught in fishing nets. Never try to dislodge a stingray from a fishing line or attempt to pick one up that is flopping around on deck.

References

• Diaz, James H. “The Evaluation, Management, And Prevention of Stingray Injuries In Travelers.” Journal of Travel Medicine 15.2 (2008): 102-109
• Rajainan, Hamid, Sajedianfard, Javid, Parto, Paria. “Study of patient's injuries by stingrays, lethal activity determination and cardiac effects induced by Himantura gerrardi venom.” Toxicon 54.6 (2009): 881-886
• Haines, Helen R., Willink, Phillip W., Maxwell, David. “Stingray Spine Use and Maya Bloodletting Rituals: A Cautionary Tale.” Latin American Antiquity 19.1 (2008): 83-98
• Barbaro, Katia C., et al. “The Influence of Environmental Bacteria In Freshwater Stingray Wound-Healing.” Toxicon 58.2 (2011): 147-153
• Ly, Binh T., Davis, Daniel P., Rao, Daniel. “Stingray Envomonization: A Retrospective Review of Clinical Presentation and Treatment in 119 Cases.” Journal of Emergency Medicine 33.1 (2007): 33-37