Freshwater stingrays were originally found in South America. They live in freshwater, unlike most cartilaginous fish, which prefer saltwater. They are somewhat submissive, but stingrays cause more human injuries annually than any other predator in Amazonian waters, thanks to a spine that constantly sheds and regrows. But how does the stingray stinger cause injury, and how can you avoid it?
What Are Stingrays?
Cousins to sharks, stingrays are boneless, wide-bodied flat fish. The body’s support system is made of cartilage, like the hard tissue that makes up your nose. Stingray fins are broad and grow the full length of the body, which gives them a round, flat shape. While swimming, the stingray moves its entire body to propel itself through the water in a wave-like motion. This is different from other species that flap their fins to "fly" through the water.
Stingrays in freshwater can grow to a width of 18 inches. The tails can be about an inch wide and as long as one foot. Though researchers don’t know how long a stingray can survive in the wild, in confinement by humans they can live up to 10 years.
Why Do Stingrays Sting?
Stingrays have a tail ready for defense. Some types of stingrays have sharp spines in the tail. A stingray will use its hard, barbed tail to attack. The small spines contain venom and can penetrate a human’s skin. The stinger will usually leave a mark and cause swelling and pain that might last multiple days to weeks. Stingray stings can also cause allergic reactions and life-threatening shock.
Despite its reputation, the stingray is gentle and shy, preferring to retreat rather than strike. It usually reserves attack mode for predators like large carnivorous fish and sharks. It will only strike a human when it feels threatened or is stepped on.
Are Stingray Stings Dangerous?
Most stingray stings require emergency care. Injuries usually happen when an unsuspecting person is swimming in a bay, ocean surf, or backwater and steps on a stingray. It may be buried in sand both in and out of water. When provoked, the stingray will push its tail up and forward, embedding the spines into a person's skin. The skin-like sheath around the spine will burst, and the venom will enter through the person's wound.
Stingray Sting Symptoms
The most common symptom of a sting from a stingray is instant, severe pain. The injury is usually limited to a certain area, but the pain can spread very fast. The pain usually reaches its greatest intensity in less than 90 minutes. Usually, the pain slowly lessens in six to 48 hours but in some cases can go on for days or weeks.
In worst-case scenarios, respiratory distress and death have occurred. More common symptoms include peripheral vasodilation — a change in blood vessels in some parts of the body to direct more blood to an injured area — which may lead to weakness, fainting, anxiety, and nausea. Other symptoms include:
- Vomiting
- Sweating
- Diarrhea
- Inflammation of lymphatic channels
- Generalized cramps
- Groin or armpit pain
The sting wound is usually swollen and jagged, with discolored edges and concentrated tissue destruction, and bleeds heavily. Wounds are often contaminated with bits of the skin-like sheath from the tail embedded. As with any puncture wound, an infection can occur.
Stingray Sting Treatment
Irrigation and debridement — when health care providers clean a wound and remove any particles of debris — are the mainstays of stingray sting treatment. The extremity containing the sting should be irrigated gently with salt water to remove contaminants like spine pieces, glandular tissue, and skin sheath. Whether you’re in the water or on land when the sting happens, do not remove the stingray spine unless it has penetrated the thorax, neck, or abdomen, it has fully severed an injured limb, or it is only weakly embedded.
Attempt to stop bleeding by applying pressure to the area around the injury. Soaking in warm water is not a verified early sting treatment, but some health care workers recommend it. After a patient arrives in the emergency room, providers should check the wound for leftover sheath. The ER staff may give a local anesthetic. If spines are embedded, they will be treated like other foreign objects. If the patient was stung on the trunk of the body, the staff should examine closely for injury to internal organs. They’ll decide whether to close up the wound or cover it and allow it to heal. Staff may administer treatment for symptoms, including medication for pain or nausea, as well as a tetanus shot. Some people may receive a prescription for antibiotics to fight potential infection.
After the patient leaves the hospital, health care providers will probably recommend rest and elevating the injured area for several days.
How to Avoid Stingray Stings
To stop an injury before it begins, do not swim in an area where people have seen stingrays. Always follow posted signs, follow lifeguard instructions, and take precautions. Stingrays like shallow warm water near the shore. They spend time lying nearly submerged here or buried in the ocean floor to hide from predators.
It can be difficult to spot a stingray partially hidden in the sand. Shuffle your feet while you are walking, which may scare the stingray away before you step on it.
If you see a stingray, avoid getting too close, and be careful where you walk and swim in areas that might be home to stingrays.