Wednesday, July 27, 2016

Things that Sting and How to Avoid Them - Part 2 - Fire coral & Stingrays

Disclaimer - I am NOT a doctor.  I am just a scuba instructor who has been around for a while and has seen (and been stung by) a lot of things.  This is not meant to replace professional medical advice or replace visiting your doctor or calling the professionals at Diver's Alert Network for advice.  If any of your symptoms are severe or are affecting your breathing or pulse, please get yourself to a hospital immediately!  



Image by Nhobgood Nick Hobgood via Wikipedia

FIRE CORALS - They come in many shapes and sizes, but their brownish orange color helps distinguish them from the other corals.  Fire corals are not true corals.  They secrete a hard skeleton and add structure to the reef like other corals, but they are more closely related to jellyfish.  Among the more commonly seen types of fire coral are branching fire corals and encrusting fire corals.  

Image by Nhobgood Nick Hobgood via Wikipedia

Image by Derek Keats via Wikipedia
Branching fire corals often have white coloration near their tips.  Encrusting fire corals can form on anything that has been underwater for an extended period of time.  Fire corals can encrust on mooring lines, dock pillars, rocks, shipwrecks, sea weed, and even other corals.

Image by Public.Resource.Org via Wikipedia

If you look very closely you can see tiny white hairs or bristles coming from the fire coral.  Each of these fine hairs contains a "nematocyst" that is barbed and contains a toxin.  Fire corals use their barbed toxic nematocysts by shooting them out to paralyze their prey (plankton) as well as to defend themselves against potential predators when they get too close.  It's these almost microscopic nematocysts that stick in your skin and cause you extreme pain when you touch fire coral.  

Image by Steel Worker 2nd Class Metro Sayre via Wikipedia
Image by Amy Kelley

To avoid getting stung, cover your skin with a rash guard or a wetsuit and keep a safe distance from the reef.  If there is a lot of surge, give an even wider cushion of safety.  Divers should practice good buoyancy control, and consider taking PADI's Peak Performance Buoyancy course to improve their control in the water.  Be aware that fire coral can encrust on any underwater surface, so avoid touching, brushing into, or grabbing onto anything underwater.  It is important not to touch things underwater for conservation purposes too - you don't want to harm any underwater organisms!  If you find it necessary to hold onto a mooring line and you are not wearing gloves, look at the line carefully before deciding where to grab it.  Avoid the parts of the line that seem to be covered in hydroids or fire coral.  Instead of grabbing the line with your whole hand use what I like to call "shrimp claws."  That means grabbing the line delicately with just two fingers.

Image by Derek Keats via Flickr

In saying that, I have been stung by fire coral numerous times.  I can tell you from personal experience that it does feel like fire.  It is not pleasant at all.  For me, the pain is usually very intense and gives me a head rush because it triggers endorphins to help my body cope with the pain.  I am usually with students or guiding divers when it happens, so I do my best to suck it up and pretend like nothing happened.  It most often occurs when there is significant surge and I am focused on helping another diver rather than paying attention to my own position in the water.

Image by Razvan Marescu via Flickr

If you do touch fire coral you will know it.  You will feel a painful, hot, fiery sting, and will probably see a welt or a rash soon after you accidentally brush up against the fire coral.  Avoid the temptation of rubbing the sting, as you will spread the toxic nematocysts around and end up getting stung even more.  Flush seawater over your sting, and when you get out of the water rinse it with vinegar.  Acids have been proven to stop the nematocysts from continuing to fire.  Later on, the sting location may begin to itch severely.  Try to avoid scratching it.  Instead, apply anti-itch medication and take Benadryl if the itching is unbearable.  Tylenol or Ibuprofen can be used to reduce the pain.  If the sting is so bad that it affects your breathing or pulse, seek emergency medical care immediately.



Image by Barry Peters via Wikipedia
Image by Richard Giles via Flickr

STINGRAYS - Despite their reputation as man-killers after the untimely death of Steve Irwin, the Crocodile Hunter, stingrays are actually very gentle creatures.  They are by no means "out to get you."  However, people can get stung by stingrays when they feel threatened.  Every creature needs a defense mechanism to survive, and the stingray defends itself by arching its tail forward and plunging its venomous sharp barb into whatever threatens it.  Stingrays only sting out of self-defense.  In Steve Irwin's case, the stingray felt threatened because Steve hovered too closely and directly above it.  In most cases when someone is injured by a stingray, they accidentally step on one.

Image by Marek Jakubowski via Wikipedia

Image by Adamantiaf via Wikipedia
Stingrays eat mollusks, shrimp, crabs, and small fish.  They can be found along the reef, in sea grass beds, and in the sand.  They shuffle through the sand, using mostly their sense of smell and electroreceptors to find their prey.  While resting, stingrays often partially bury themselves in the sand.  Stingrays are quite incredible to watch.  They use their spiracles, the openings behind their eyes, to take in water and to expel the undigestible bits as they filter through the sand for food.  Next time you are snorkeling or diving and find a stingray, take some time to observe it, but give it plenty of space. 

Image by Tomas Willems via Wikipedia

Image by Jlwelsh via Flickr
To avoid any negative encounters with stingrays while diving or snorkeling, do not touch them or corner them.  Especially avoid hovering above them, as that is their strike zone if they feel threatened.  While hanging out at the beach, shuffle your feet through the sand so you don't accidentally surprise a stingray hiding in the sand.  

Image by Andrew Beckwith via YouTube

I cannot say firsthand how badly a stingray sting hurts, since I have never been stung by one.  However, I am certain that it is an extremely unpleasant and very painful experience.  It would be like being stabbed with a serrated knife, plus the effects of the venom.  

Image by Freebin via Wikipedia

If you get stung by a stingray, stay calm.  Remove the stinger (unless it is in a vital organ, such as with Steve Irwin).  Apply pressure to stop the bleeding.  Evaluate the severity of the symptoms, and determine whether or not emergency medical care is necessary.  Typical symptoms include pain, swelling, bleeding, and muscle cramps.  If bleeding is severe and uncontrollable or breathing or circulation are affected, consider it a medical emergency and get to a hospital immediately.  If it's not an emergency, soak the wound in hot water (but don't burn yourself!) for 30-90 minutes to deactivate the venom and relieve the pain.  You can take a painkiller such as Tylenol or Ibuprofen to ease the pain, and an antihistamine such as Benadryl to relieve itching and swelling.  Keep the wound clean and monitor it for signs of infection.    

Image by Symac via Wikipedia

Diver's Alert Network, also known as "DAN," is the dive industry's number one dive safety resource.  Every diver should have their phone number, since they are the best resource for dive safety.  They have a 24 hour emergency hotline, as well as an information line for non-emergency medical questions.  Even non-members can get free advice.  I highly recommend becoming a DAN member, since they provide affordable and high quality dive insurance, travel insurance, a monthly magazine called "Alert Diver," and a wide variety of dive safety educational resources.  

DAN Non-emergency medical information line
Mon-Fri 8:30am to 5:00pm EST.

A big "Thank You!" to our local diver John F. for suggesting this blog topic!  I look forward to hearing everyone's ideas and suggestions for future blog topics.  Feel free to leave comments on this blog or on our Aqua Action Divers Facebook page.

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