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Crayfish, Crawdads, Yabbies, Ditch Bugs Trauma

FAQs on Crayfish Disease: Crayfish Disease 1, Crayfish Health 2, Crayfish Health 3, Crayfish Health 4, Crayfish Health 5, Crayfish Health ,
FAQs on Crayfish Disease by Category: Diagnosis, Environmental, Nutritional, Infectious, Parasitic, Social,

Related Articles: Forget Crawfish Pie, Let's Make a Crawfish Tank! By Gage Harford, Invertebrates for Freshwater Aquariums by Neale Monks, Freshwater Shrimp, Crayfish, "Lobsters", Prawns Freshwater to Brackish Crabs

Related FAQs: Crayfish 1, Crayfish 2, Crayfish ID, Crayfish Behavior, Crayfish Compatibility, Crayfish Selection, Crayfish Systems, Crayfish Feeding, Crayfish Reproduction, Freshwater Invertebrates/Use in Aquariums, Freshwater Crustaceans for the Aquarium, FW Crustaceans 2, Fresh to Brackish Water Crabs, Hermit Crabs,


Blue crayfish injury      6/14/17
Hi there, I have a blue crayfish and whilst moving it from the tank for cleaning (I scooped it up in its terracotta cave ) I tried to pick it up... it jumped. ..! I jumped.., dropped the pot and banged it's head!
The injury is about 4weeks old. Is this injury likely to kill it? It looks no worse after these weeks.
<That the animal has survived this long is a good indication that it will persist; and clear this crack with the next moult or two.
You do administer Iodide regularly? I'll list the reading: http://www.wetwebmedia.com/fwsubwebindex/crayfishdisfaq.htm
Bob Fenner>

Re: Blue crayfish injury     6/14/17
Yes, marine iodine, half dose as specified in your previous q&a's. Will it moult again though?
<Yes; if it lives>
It's approximately 3yrs old, I didn't expect it to get any bigger, though I'd be delighted if it did.
<Moulting frequency decreases with age/size, but never stops altogether>
Does the head area moult too?
Is the discoloured fur on its pincers normal or should I attempt to remove it?
<Looks like algae of some sort... this will come off w/ the moult>
Thanks for your swift response
<Welcome. Bob Fenner>

Yabbie Question for the forum      8/26/16
Ammonia = 0
Nitrites = 0
Nitrates = >40ppmm

GH = 29*
Kh = 5*
One drop iodine during 1/4 water changes each week.
I teaspoon aquarium salts at each water change.
I chunk of cuttlefish bone, two filters with aeration, two good hiding places.
Hi there,
I hope you are still answering Yabbie questions!
<We try!>
I have a blue yabbie, approx 10cm in length in a 38 litre tank - have had him for 5 months, for the first month he lived in a 25 litre tank. He moulted after 4 weeks and then again 4 weeks later but not since.
<Moulting becomes less frequent as they age. At maturity, they may moult very infrequently, maybe even once a year, if that. In any case, the triggering factors are multiple, and not just good diet, but also availability of calcium and iodine, temperature, even day length.>
About 6 weeks ago he escaped from his tank during the night when one of the children moved his tank cover, and was found at midday the next day on the floor under shelves near his tank - so was out probably for at least 8 hours- and returned to the tank (I put him straight back in, not realising that wasn't a good idea).
<No worse than leaving him out of the water! Definitely did the right thing.>
He lost the top 2/3rds of his large antennae during the escape and was very 'wobbly' when moving around for about a week afterwards, kept his tailed curled under all the time and generally looked a bit traumatised.
<I bet.>
He is now physically as he was before, but has been very reclusive and has not eaten much (I used to feed him algae wafers daily and occasionally dried shrimp or goldfish pellets, but less frequently now since he doesn't seem hungry). I see him pick something up food every four days or so but often he just drops it immediately and goes back to hide. My questions are - would the loss of antennae make him unable to detect or eat food?
<Absolutely! For a crayfish, these are the main instruments used to sense their world. Their eyes are far less useful, mostly used to detect movement and shadows that help avoid predators. But the antennae are used to detect dissolved chemicals and probably vibrations in the water too, and these
help them find food.>
Is 3 months too long between moults for such a little guy?
<Nope. Wouldn't worry about. I don't know if crayfish ever stop moulting completely, but they can certainly go months between moults.>
GH seems high - is it too high?
<Nope; hard water is ideal. Actually, carbonate hardness is even more useful. Your water is fine.>
His tank is in a warm low-light bedroom and is generally at 22-23 degrees - should I move the tank or make it warmer?
<Neither. But the only thing I'd suggest doing is freshening up the tank a bit. Give it a good clean, and do a series of decent water changes across a few days, perhaps a third of the water each day, so that his entire world improves. Get rid of any decaying organic muck that will be sucking oxygen out the water. Don't bother adding food for a while if he's not interested.
After a week of starving him, offer him something really good, like a small unshelled shrimp or a small opened mussel. Something with a good strong
smell. See if he shows an interest. If not, remove; but if he's happy, let him dine like a king!>
Have you heard of long-lasting damage from an escape or am I anthropomorphising him?
<Neither. Just because an animal doesn't think like a human doesn't mean it doesn't think. In his own way, yes, he had a rough time and it'll take a while for his brain (such as it is, perhaps) to comprehend that his life is now safe and cozy, and that he doesn't need to stay in an alarm mode. In the wild, crayfish do get beached when it's a dry spell, and might be holed up in a burrow for weeks. Their bodies switch over to a sort of suspended animation that keeps them from needed as much food or oxygen. All very useful. But if he's been switched into this mode now, it might take several
days to switch back to his normal mode. Make sense? I just don't know. But I'd speculate that if he's moving about and breathing, he'll be fine, but he just needs time to readjust.>
On that note, what can I do to cheer him up, and/or encourage mouthing so he gets his antennae back?
<Moulting will fix any/all physical damage like this. May take time though, i.e., more than one moult.>
Many thanks for the amazing website, I use it a lot.
<Welcome. Neale.>

Blue crayfish injury?       8/29/15
Good evening,
<Good morrow here now Sheila>
We have a question about our blue crayfish. He managed to climb up into a rock decoration in our cichlid tank. He was in there for a full day and we could see him, twice, try to get out and was unable to squeeze out the hole.
<Unusual.... should be able to get out of anything it can get into>
We left him alone while turning the rock cave upside down hoping he would get out. We became concerned after an entire day/night in the rock/decoration so we decided to break the rock to get him out. We did not break the rock where he was but next to where he was. He was finally able to crawl out on his own but now we can see what appears to us as "white
flesh" popping out the top of his shell right behind his head. He is now hiding under a log, one he can't climb in, and is on his "tip toes" so to speak. Is there anything we can do to help him?
<Yes; this physical injury will heal sooner given good water quality and nutrition. Plus, I'd up the dosing of iodine (ide-ate actually) here.
Please read: http://wetwebmedia.com/CrayTraumaF.htm
and the linked files above; till you feel confident in how to proceed>
Thank you,
OD Family
<Welcome. Bob Fenner>

Crawfish dying within 24 hours   4/10/13
<Hi Eric, Rick here>
I live near a store that regularly offers live crayfish for sale.
<I know you don't live near me, crayfish are a rampant invasive species in Arizona and are therefore restricted by Game and Fish!>
With my young daughters prompting, I've tried twice to pick a lively one out of the box and place it into a well established aquarium.
The test strips all read okay and I had a submersible filter in for filtration and supplement air.
Both specimens died within a 24 hour time period.
After researching care for these guys, I can't seem to find a reason for them not to be making it.
If there was something wrong with the tank, I would think they'd at least make it longer than a day.
Any ideas would be helpful.
<The only thing that comes to mind for me at the moment is that perhaps they weren't properly acclimated to the tank. What procedure did you use to make the transfer from plastic bag to tank?>
Re: Crawfish dying within 24 hours 4/9/13– 04/10/13

Hey Rick,
Thanks for the quick response.
Honestly, I took them out of the bag and placed them into the tank.
Keeping in mind these guys were sitting in a crowded box with no water at the store, I figured the sooner I got them into the water the better.
<Hmm. I'm not sure what you can do here because every acclimation process always assume the fish starts in water. Could there have been a large temperature difference between the bag and the tank water?>
The second time I tried, the crawdad lived over 24 hours in the tank and was very active and feisty. Next day, he was gone.
<It certainly sounds like stress of some kind.>
I wonder if what they've been through to get to market is just so traumatic,
they don't have much of a chance past a certain point.
<Possibly. You might try easing them into water. Empty your tank and form the substrate so there is a hill. Put enough water so there is a pond on one side of  the tank and dry land on the other side. Place the crawdads on the dry land part and let them enter the water on their own. Once they are in the water regularly, add a half gallon at a time until the tank is at the desired level. Also, take a look at this website I stumbled across.
http://lifestyle.iloveindia.com/lounge/crayfish-care-13248.html   It has some ideas on how to transfer, but again, it assumes the fish starts in water.  It might be that being out of water at the store is the root cause.
Their gills must be moist to work properly in air. Actually, as I proofread and think about this some more, I wonder how long the fish has been completely out of water. Could be the gills are already dried and damaged before you bought the crayfish.  - Rick>

blue crayfish stuck in shell    9/18/12
Good afternoon,
I bought a blue "lobster" from the pet store back in May, and this is the first time he molted. I noticed his old tail is still stuck over the new one. I'm not sure how long it's been like that since he molted while I was sleeping. Do I just leave him and eventually he'll get it off on his own?
Will this cause damage to his tail?
Thank you,
<Do you provide supplemental iodine supplement (actually iodate/iodide) in the form of marine aquarium iodine drops? Failed/improper moults are a VERY common symptom, result of not providing iodine. In a normal moult the entire moult should come off and usually the crayfish turns right round and eats it, recycling the calcium therein. If the moult doesn't detach completely, that's bad, and tends to imply a problem with moulting (ecdysis, do read online re:). There's no fix, and if the crayfish will recover, it will under its own steam. But do acquire, use iodine supplement (or at least an iodine-rich food, e.g., seaweed, sushi Nori). Cheers,
Re: blue crayfish stuck in shell    9/18/12

<Just in case Neale is out for the day (he's in the UK), am responding as this appears to warrant prompt response>
So don't try to pull it off? Just let him do it?
<Don't pull, let this animal "do it">
Will the iodine effect the
other fish (a Pleco and dwarf gourami)?
<Will not affect negatively>
And is the iodine with the saltwater stuff?
<It is>
 Last time I asked for it the employee gave me a strange look and told me I don't need it.
<Search WWM re Crayfish and Iodide-ate... they DO need it, along w/ adequate alkalinity and alkaline earth presence. Bob Fenner>
Re: blue crayfish stuck in shell    9/18/12

So don't try to pull it off?
<Not a good idea.>
Just let him do it?
<If he can, he will.>
Will the iodine effect the other fish (a Pleco and dwarf gourami)?
<Well, since you shouldn't keep crayfish with tropical fish this is normally not an issue. But no, the iodine supplement is safe if used as instructed. You only need about half the dose quoted on the bottle.>
And is the iodine with the saltwater stuff?
<Correct. Do note that while we're throwing around the term "iodine" here, speaking of the element, we actually mean iodide or iodate salts, so NOT the iodine solution (tincture) used to clean cuts and sold in drugstores.
If memory serves, it's potassium iodide that's normally provided to invertebrates like crayfish.>
Last time I asked for it the employee gave me a strange look and told me I don't need it.
<The world is full of contradictions. Do you research, reading and then come to your own conclusions. There's an ample literature re: ecdysis of crustaceans and the key role played by iodide/iodate. Cheers, Neale.>

blue lobster, injured    6/11/12
I have a blue lobster and have had him for about 2 months. Last night he escaped from his tank and fell about 15 feet
onto tile. We found him still alive this morning (not sure how long he was out of the tank) and put him back in his tank, but he isn't moving much and appears to have trouble moving his left side. He did eat an algae wafer we put into his tank, but still isn't moving much. Is he suffering, or will be able to recover from the fall? We aren't sure what to do.
<These animals can be very tough... even if the exoskeleton was cracked... given good care, food... it should recover and molt to having a full test in time. Read here re: http://www.wetwebmedia.com/FWSubWebIndex/crayfishdisfaq.htm
and the linked files above. Bob Fenner>
Re: blue lobster   6/12/12
Thank you for your reply. We'll see what we can do and hope he makes a full recovery!
<Ah yes, BobF>
Re: blue lobster   6/12/12

Yes, about 15 feet. He got out of my son's room and crawled into the hall and fell through the banister to the foyer below. It's a 2 story foyer and there's no carpet so he fell directly onto the tile. My husband found him on his back, but still alive.
<Yeeikes! And yay! B>

Crawdads pinchers 11/11/09
My crawdad is five years old. He was molting and his pinchers got caught in the old and I had to help him. However, he was caught for about seven hours cause I thought he would eventually get them off. Now that they are free, his pinchers are upside down and he stays on his back. It's freaky.
If I cut his pincher/pinchers off at the base, will he still live? help!
<I wouldn't pull the pincers (not pinchers!) off since that requires a great deal of force, and you're likely to damage the crayfish in the process. It would certainly be very traumatic for the animal. Much better to let nature take its course here. Do note that many "failed" moults come down to insufficient iodine, and for freshwater crabs and crayfish, supplying iodine really makes a big different in terms of success. Some crustacean-specific pellet foods may cover this aspect of things, but otherwise use a standard marine aquarium iodine supplement at about half the quoted dose. Cheers, Neale.>

Found a crawdad in our backyard 6/18/2009
Hi my name is Deanne I live by Castaic Lake. Today my daughter found a crawdad in our backyard, and we have no clue as to how it could of gotten there.
<Most often carried/dropped by dogs, cats, raccoons, birds, and so on.>
We had Terminex come and spray for pesticide yesterday, and Im afraid it might of ingested some of it.
<May well have done, or else simply damaged or stressed by being carried and dropped out of water.>
He was still alive when we found it, but moved it a couple time not sure where to put it. We finally decided that the fish tank was the best place for it. It seemed to be doing fine, moving around etc, but after a while it kinda just fell over onto its side and hasn't moved since. Nothing but a few leg twitches and a claw closing but tats it, is there anything we can do for the poor thing?
<Probably very little; by all means improve circulation and oxygenation, and ideally provide water that isn't too warm if this you live in a temperate zone area rather than the tropics. Observe, and if the thing dies, do remove the body quickly.>
Thank you
<Good luck, Neale.>

Blue Crayfish Dear Crew, especially Sabrina, <Sorry, I stole the email from Sabrina, Gage here, your local Crawdaddy fanatic.> I have a little blue crayfish, nearly 3" long, 2 years old, called Lopez. At the last molt (Sunday) he got a leg stuck and when he finally got it out, the leg/pincer was at an odd angle, kind of backwards, clumsy looking. He is moving and eating (lots) and can still use the leg and pincer, but it is certainly not right. It is bent backwards and gets in his way when he tries to hide in his jar/burrow, though he gets in in the end. I am wondering whether to somehow tweak it off (ouch) so he can grow a new one. But really, I am scared to hurt him and would rather think he will be fine and that he is not in pain as he is. What do you think? How can I tell? And if you think I really must tweak it off, any advice on how to do so...?? I really like this little fellow and want to do my best for him. Any help appreciated. <I vote to leave it, I do not think it is worth the stress of breaking it off. Chances are he will correct it himself in the next few molts. Best Regards, Gage> Cheers, Andy
Blue Crayfish, cont'd
Many thanks for the swift reply. I am inclining towards leaving it. <I definitely agree with Gage here, better to leave it.> If he was in pain, I think I'd see differences in his behavior wouldn't I? <I would think so, yes. If he's eating, acting normal, let 'I'm be.> He looks to be acting as usual, but with a dicky leg... Andy <I would strongly recommend adding iodine to his tank if you don't already, and if you do, to increase the amount by just a bit until his next molt. I use Kent marine iodine, at a rate of one drop per ten gallons every week. Wishing your lame pal a swift recovery, -Sabrina>

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