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checkyourmirrors
December 17th, 2008, 10:45 AM
While diving in Coz last week I rubbed up against what looked like black weeds where my skin was exposed. It caused immediate pain similar to bee stings that lasted a few minutes. Almost like underwater stinging nettles.

Does anyone know what this was and I didn't think it was fire coral?

driftin' by
December 17th, 2008, 11:47 AM
I always known it to be called hydra which happens to be a type of fire coral.
Stinging Hydra Is A Close Relative Of Fire Coral- Suite101.com Images (http://www.suite101.com/view_image.cfm/507811)

ggunn
December 17th, 2008, 11:48 AM
While diving in Coz last week I rubbed up against what looked like black weeds where my skin was exposed. It caused immediate pain similar to bee stings that lasted a few minutes. Almost like underwater stinging nettles.

Does anyone know what this was and I didn't think it was fire coral?

I've always heard it called "hydroid". It's a colony animal related to jellyfish. Usually one encounter such as yours is enough to get you to pay attention and avoid touching it. I know it was for me. ;^)

driftin' by
December 17th, 2008, 12:18 PM
Gordon has the correct scientific name, it's definately a hydroid (http://www.marinelifephotography.com/marine/cnidaria/hydroids.htm). 'Hydra' is just my Spanglish interpretation I've gotten over the years from DM's. In any event, once you've encountered it, you'll never forget it!

Dave Zimmerly
December 17th, 2008, 12:33 PM
Yeah, I got stung on my hand both in May and November (same hand!). Since I dive with my hands behind my back, it's still a mystery how I came into contact with it.

Takes about a month for it to heal.

Regards,
Dave (aka "Squirt")

Sue Sue
December 17th, 2008, 01:08 PM
It leaves the most delightful raised red rash as well :doh: This stuff really stings and it does take 4-6 weeks to completely heal. You can try topical treatments, but I have yet to find anything that really helps. I too got hit with this stuff... twice. Once, I admit, due to my error, with another occurrence from out of the blue, literally.... I was going along, in the middle of nowhere, away from any coral or reef and POW, huge sting on my ankle. Once on top, I had the same hive like rash that I had from the prior incident. Could it perhaps come from floating hydroid that had broken off somewhere else? Or maybe just from another type of stinging critter of sorts. Maybe this is what happened to you Dave. ???? Regardless, hydroid is a very good reason to pay close attention to buoyancy.

driftin' by
December 17th, 2008, 01:28 PM
Could it perhaps come from floating hydroid that had broken off somewhere else? Or maybe just from another type of stinging critter of sorts. Maybe this is what happened to you Dave. ???? Regardless, hydroid is a very good reason to pay close attention to buoyancy.

Or are the symptoms just delayed? That seems to have been my experience with it... it'll take a few moments to realize you had an unfortunate encounter. And I've seen broken bits of it floating around and have done what I can to avoid it. So I guess anything is possible?

Prop Joe
December 17th, 2008, 04:12 PM
Yup, Hydroids. You will see the dive masters with the same issue's from the dang things. I get stung by them every year. No matter how careful I am I always seem to get stung. Easy to brush against while chasing critters with camera as they do not show up through the view finder. I've also been setting up for a shot in close quarters and had another diver swim above me blowing the hydroid into my hands with one kick of their fins. Get the strongest hydroquartizone cream you can and apply frequently. That is the only thing that seems to help my skin. I've also tried scraping the stingers off with the backside of my EMT shears before surfacing... Seemed to help. Takes a few weeks to go away. Mileage may vary.

cduffey
December 17th, 2008, 05:07 PM
My husband seems to encounter it just about every time we're in Coz. His reaction is almost like poison ivy and the docs treat it like they would treat a poison ivy reaction.

parrotheaddiver
December 17th, 2008, 05:39 PM
Yup...been there done that:D

Christi
December 17th, 2008, 05:40 PM
You've gotten great info...and just to confirm from a DM/Instructor's perspective...yes...they can be broken off and floating. A few weeks ago while doing my ascent I felt a sting on my hand. I was in mid-water column, so it wasn't from brushing up against anything. A day or two later, I had a rash on my hand. It takes three to four weeks to completely go away. Applying vinegar as soon as you get back on the boat helps, but since it's too late for that..apply hydrocortizone cream often and be very careful about scratching it...it actually can spread.

FishOutUvH2O
December 17th, 2008, 05:44 PM
This was taken last month in Cozumel, a couple of days after my encounter with a Hydroid. . .
http://i179.photobucket.com/albums/w303/EnviroCon/DSC_0411-2.jpg

There are several "remedies" that people suggested to deal with the itching:
1. Divemaster urine- This just wasn't going to happen!!!
2. Vinegar- I tried this and it helped a little.
3. Hydrocortisone (in Spanish Hidrocortisona) cream, 2.5%- This stuff worked the best. You can get it at pretty much any of the pharmacies down there. Make sure it's the 2.5% one. It's prescription strength, so use it sparingly.

BTW: Don't let Christi (BlueXTSea) see it or she'll scold you for touching the reef!

ggunn
December 17th, 2008, 06:26 PM
Or are the symptoms just delayed? That seems to have been my experience with it... it'll take a few moments to realize you had an unfortunate encounter. And I've seen broken bits of it floating around and have done what I can to avoid it. So I guess anything is possible?

Not for me. I got hit on the back of my hand by a hydroid a few years ago and it was like an electric shock the instant I touched it.

Sue Sue
December 17th, 2008, 06:29 PM
Thanks Christi for letting us know that it can free float and still do its damage. The second time this happened to me I was actually upset because I didn't think I had come in contact with anything. Also, the one thing that did help a little bit, once I got home was ...of all things, Preparation H. At least the swelling and redness went down somewhat, but it didn't take the itch away. I guess I should have been more aggressive with the Hydrocortisone. Hope I don't have a next time. S

driftin' by
December 17th, 2008, 06:55 PM
Not for me. I got hit on the back of my hand by a hydroid a few years ago and it was like an electric shock the instant I touched it.
Interesting... I guess like a bee sting, people react differently. Also, mine never looked as bad as FishOutUvH2O's! Dude, that looks nasty. Ouch! I know one of the times I got it, I was getting in tight to photograph a pesky juvenile spotted drum with my camera and one raked the back of my hand. Other then jerking away thinking I was touching something precious, there was no immediate pain... just a persistent itch that followed with little swelling.

FishOutUvH2O
December 17th, 2008, 07:37 PM
. . . Also, mine never looked as bad as FishOutUvH2O's! Dude, that looks nasty. Ouch!
It looked far worse than it felt. I only vaguely remember running into it. It never really itched that bad and has pretty much disappeared. It's scary when you find out what caused it, because those little buggers are everywhere down there. It's kind of funny because random strangers will see it and just say, "Hydroids or jellyfish?" So it's a great conversation piece. Still, I don't recommend touching them if you don't have to.

Christi
December 17th, 2008, 08:49 PM
BTW: Don't let Christi (BlueXTSea) see it or she'll scold you for touching the reef!

HEY! Be nice...haha! I didn't scold you that bad :D

deborahdelamar
December 18th, 2008, 02:18 PM
Usually you'll feel it when you are stung by hydroids -- little prickles, not painful. Best to treat the site immediately with vinegar or ammonia to dissolve the bits that are in your skin (jes, Windex is good.) Don't rub! When it starts to itch, soak in the hottest water you can stand for as long as you can stand it. Treat the itchies with whatever works for you: Antihistamine caps or topicals, hydrocortisone cream, or simply seal from the air with hairspray (hairspray works great for itchy bug bites, too.) There's also a cream that's sold at American Pharmacy on Calle 3 near the waterfront that works well for the initial rash -- don't remember the name; starts with an "A." The itching shouldn't last more than a few days. When it stops, treat the rash with anti-scar cream or hydrcortisone cream. The rash takes from about 10 days to a month to dry & heal. It's fine to dive with it but seawater slows healing.

Dave Zimmerly
December 18th, 2008, 04:36 PM
I found that lots of hot water did help and a product called "Xyloderm" sold at Cedrual (sp?).

Regards,
Dave (aka "Squirt")

drbill
December 18th, 2008, 05:55 PM
It would be interesting to see pix of this species. I dove Belize for several months and didn't have a problem (but I recognized several of the stinging hydroids there). We also get free swimming siphonophores (relatives of the Portuguese man of war) out in Catalina waters that may break up and leave welts if they come in contact with your skin).

deborahdelamar
December 19th, 2008, 10:37 AM
Do any of you photographers have shots of Punta Tunich Dropoff for Dr. Bill? (That site's a carpet of them, so they should be very easy to see.)

driftin' by
December 19th, 2008, 11:03 AM
It would be interesting to see pix of this species
I only take pictures of things I like. :D Actually I'm sure I have one but it's easier to find someone else's example on the net. I don't want to post someone else's work so you'll have to click the link below. I think this is a good example of the one we're talking about?

http://reefguide.org/pixhtml/stingingbushhydroid1.html

ggunn
December 19th, 2008, 11:22 AM
I only take pictures of things I like. :D Actually I'm sure I have one but it's easier to find someone else's example on the net. I don't want to post someone else's work so you'll have to click the link below. I think this is a good example of the one we're talking about?

Stinging Bush Hydroid - Macrorhynchia robusta - Isla Mujeres, Mexico - Photo 1 - Tropical Reefs (http://reefguide.org/pixhtml/stingingbushhydroid1.html)

Oh, yeah, that's the stuff all right. When the picture popped up it made me want to jump back from my computer. ;^)

driftin' by
December 19th, 2008, 11:50 AM
:lol: Me too!

budaman
December 19th, 2008, 01:38 PM
Gee, and all this time I thought this was just a cool looking coral. Glad we didn't brush up against it! Took last May on our trip.

Mike

http://gallery.mac.com/csealove/100105/IMG_0377/web.jpg

Sue Sue
December 19th, 2008, 03:56 PM
Oh what a delicate, feather-like, airy, harmless looking little bush...:evil: As I mentioned, I have encountered this stuff twice....not something I want to happen again. Thanks for the photo Sue

down4fun
December 20th, 2008, 10:23 AM
Thanks to all for the information. I just returned from Coz yesterday and my Left hand shows the battle scars of some free floating nasties. I think the little college princesses next to me on the plane were afraid I was contagious. It was actually kind of fun in my own sadistic way:crafty:

drbill
December 20th, 2008, 03:28 PM
Fortunately I've experienced a number of species of hydroid with stings that can cause welts, so I would recognize this critter as most likely one of that group. Don't remember seeing it further south in Belize, but knowing what it was I might have just ignored it. Thanks for the pix.

caseybird
December 21st, 2008, 04:49 PM
Whenever I talk to non-divers about diving, they always ask me if I'm scared of sharks. Of course, I put on my best "sea hunt" face and tell them that's all part of the job, nothing to worry about. I usually don't tell them what really hurts is the little stuff that doesn't move. If it's on a reef, looks helpless and can't possibly hurt you, It's full of stingers.
Someday I'll get home from Coz sting free.

ggunn
December 21st, 2008, 05:48 PM
Whenever I talk to non-divers about diving, they always ask me if I'm scared of sharks. Of course, I put on my best "sea hunt" face and tell them that's all part of the job, nothing to worry about. I usually don't tell them what really hurts is the little stuff that doesn't move. If it's on a reef, looks helpless and can't possibly hurt you, It's full of stingers.

On a long ago Coz trip, before I was a diver, while out snorkeling I picked up a bristle worm. Lesson learned, the hard way. ;^)

naitram
December 29th, 2008, 01:01 AM
I ran into that stuff in the first 10 minutes of my first dive a couple weeks ago. My hand still looks pretty disgusting.

NOT fun stuff.

Sue Sue
December 29th, 2008, 10:57 AM
I ran into that stuff in the first 10 minutes of my first dive a couple weeks ago. My hand still looks pretty disgusting.

NOT fun stuff.

Stick with the hydrocortisone ointment/cream or even try my Prep H treatment..I know it sounds crazy but it kind of sort of helped with the red swelling aftermath from my last encounter. Also, try not to scratch it, this stuff can really drive you crazy :wacko: Good luck ! Sue

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