How You Can Help Fiddler Crabs

Over the years since i acquired my first fiddler crab i have learned quite a bit and written about what i've learned here.  This blog refers to the fiddlers a lot even though it is a blog i started for basically whatever random things i could come up with.  Anywhoo, on this journey of raising fiddlers and writing about them i have learned that resources about their behavior in captivity are hard to come by.  Really, information on fiddlers at all is kind of hard to come by.  There are basic pages describing tank set up but nothing really digs into the life of the fiddler crab and what all it will need aside from its tank set up.  This is an area all you fiddler caretakers can help with.  If you have fiddler crabs, write about them on the internet.  Start blogs or just put in forum entries about them on aquarium forum websites.  The more accurate resources people have on these creatures the better off the fiddlers will be.  We can teach people with our experiences and observations.  Others can learn from our mistakes and our triumphs.

These little creatures are sold off as cheap throwaway pets, which is ethically deplorable, but if we band together and show that they are just as valuable as any other marine animal then we will be helping them.  Write about their behavior, their needs, what foods they like, how you interact with them, how you maintain their aquarium, what diseases they may be experiencing and what you did to remedy those diseases if you found anything that actually worked on them.  All of that is necessary information.

A huge issue exists regarding a total lack of information about diseases that fiddler crabs get in captivity.  There are a host of parasites, fungi, bacterial and viral infections that fiddlers can likely get but little is written about these diseases and even less is available on the internet.  The information i've found deals with other larger species of crab, it seems likely fiddlers can get the same or similar diseases, but i'd like to be 100% sure just what diseases the fiddlers can get.  So if you have a knowledge of fiddler diseases, by all means post your information on the internet.
Even if you don't know what disease your crab has, post pictures if it has physical symptoms, if it dies, this will sound morbid, but do a little inspection to see if there are visible parasites, deformities, or fungi.  If you happen to have a microscope, even a junior microscope that kids can get at wal-mart, put the organs and body parts under it and observe them, write down what you find.  Sometimes we have to do our own science so we can become better at what we do.

We have these creatures usually because we love them.  If we want to give them what's best, we need to fully understand them and that can only happen through sharing information and resources.  So if you have fiddlers, write about them every chance you get, document their behaviors that seem out of the ordinary, note any physical anomalies.  This is how we all learn and how we help our crabby little friends, through experience, through discussion, through observation, and through sharing.

Steve the Fiddler

Steve is my little trooper, i've had him since 2013 and he has gotten rather large.  I do wonder if he is approaching the end of his lifespan as he has become less active and prefers to spend most of his day hiding.  His molt frequency has declined as well.  When i brought him home he was rather large, which indicates that he was older when he was captured and shipped.  I'm holding out hope for him though, he does still come out occasionally and will still get out of the way if disturbed so i'm not going to give up on him.

Chlorine Dioxide, Kerri Rivera, and Why Kerri is Evil Scum

I must note this article will be brief and it will contain obscenities.

This past year it came to my attention that quacks and sociopaths looking to make money are peddling dangerous and lethal autism "treatments" and "cures" online.  There is an evil sociopathic woman named Kerri Rivera behind a very damaging movement that involves giving autistic children multiple chlorine dioxide enemas a day.  In some cases the scary bitch recommends feeding the children chlorine dioxide. 

For those that don't know, chlorine dioxide is a gas and is used as a bleaching agent.  It is used primarily in the paper making process (to make paper white) and in water treatment as an antimicrobial (by the time it makes it to the tap it is so diluted it isn't likely to cause any bodily harm).  When mixed with water chlorine dioxide forms chlorite ions.  In drinking water the max allowed chlorine dioxide levels are 0.8 milligrams per liter, the max for chlorite ion is 1.0 mg/L.  Larger concentrations of chlorine dioxide and chlorite can cause inflammatory responses and they are gastric irritants.  The body removes chlorine dioxide and chlorite through the kidneys.  Animal studies have shown that high concentrations of chlorine dioxide can cause brain development hindrances during the fetal and postnatal phases.  In humans chlorine dioxide inhalation has been shown to reduce the blood's ability to carry oxygen throughout the body and, if more is inhaled, it can lead to pulmonary edema (the lungs filling with fluid and thus drowning the individual).  Skin contact can cause chemical burns and rash.

While many backward fools support the chlorine dioxide treatment regimen as a cure for autism (there are no cures for autism), it is not a cure nor is it a proper treatment.  By administering the chlorine dioxide (often referred to as MMS aka miracle mineral solution) by way of enema, the intestinal linings of the autistic individual are "melted" off and excreted through the anus.  Kerri Rivera, a horrible sadistic bitch that i wouldn't mind seeing strung up and gutted (i don't care who reads that, she's a horrible human being that shouldn't be allowed to continue to exist), tells these foolish, easily brainwashed, easily led parents that the intestinal linings are "rope worms".  The evil sadistic bitch refers to autism as a parasitic infection.  There are no such thing as rope worms and anyone with the most basic understanding of parasite anatomy can clearly tell that the intestinal linings are NOT worms at all.  The parents, when first noticing the shedding of these mucosal linings, will often send them for parasite testing.  The tests come back negative for parasites.  Kerri Rivera then tells these deluded saps that the scientists/doctors were lying and that big pharma is covering up that autism is caused by parasites.  This is how she sells her product and this is how the sociopathic bitch is making her millions.  Meanwhile, while this twisted scum bitch is peddling her products, children (mostly in the US but this is catching on in other countries too) are suffering at the hands of their own parents.  By giving chlorine dioxide enemas to the children and continuously damaging the intestinal linings, it causes chronic inflammation which sets the child up for colon and rectal cancer later in life.

Knowing she can profit off the stupidity and conspiracy cultism, Kerri Rivera also peddles CD for the treatment of other ailments such as cancer.  She has a book out about how to cure autism using this method and she has a facebook group where she tells parents not to use their real names and not to tell people they're using the protocol.  Child protective services have been called on some parents and some cases are ongoing.  If you know anyone doing this to their child, please call your local CPS and turn in the parents.  You may be wondering why the bitch Kerri is still free.  She hides in Mexico and, scary as it sounds, there is a cult that is connected to this ridiculous protocol so that it can fall under religious protections in some areas just like faith healing falls under the same bullshit religious protections.  I invite you to please join the facebook groups listed at the bottom of the article.  Bitch Kerri has to come out of hiding eventually and when she does we need to make sure she gets put in prison or mysteriously disappears (whichever comes first). 

Do note that the opinions (that the bitch should be eliminated) in this article are my own and do not reflect the views of the facebook groups (they just want her imprisoned).  I do not run any of the facebook groups and do not want them to receive any bad press or bullshit for anything i might say.  They're doing good things and exist to save children from the wrath of incredibly stupid parents.

https://www.facebook.com/pages/Stop-Kerri-Riveras-Abuse-of-Autistic-Children-and-Adults/594889167310547?fref=ts 

https://www.facebook.com/fightingcd?fref=ts

https://www.facebook.com/pages/ADHD-ASD-Myths-Misinformation/658534877602198?fref=ts

Lastly, stay away from Generation Rescue, they support the idiocy of the anti-vax and anti-autism movements.

Natural Rocks in the Fiddler Aquarium

This is going to be a brief article as i am limited on time at the moment but feel this issue should be addressed, even if just briefly.

While many of us look to save money by taking rocks from our yards, local lakes/rivers/ocean side to use in our fiddler crab or aquarium tanks, it may not be such a wise idea.  Rocks generally contain minerals and some metals and those minerals and metals can be dangerous to the aquarium environment.  A lot of rocks contain calcium and/or magnesium, which can pollute a tank by raising ph and water hardness.  Some rocks contain copper, zinc, and iron.  Copper is incredibly dangerous to aquatic invertebrates and iron should be kept out of the aquarium as should zinc because both can poison aquatic animals.  Some minerals can raise or lower the ph of water.  When the ph of the tank gets lower, some metals in certain stones that were once "inactive" can become "activated" and leach into the water to cause havoc for the animals in the aquairum. 

Calcium is fairly easy to test for in rocks.  You can put white vinegar on a rock to see if the rock will give off a bit of fizz/bubbling.  If it does, calcium is present and that rock should not be put in a tank with animals.  Iron is somewhat easy to spot in some rocks exposed to rain and the elements, it takes on a rusty orange appearance.

As a general rule, avoid rocks that you can scratch easily with your nail, that can break easily (like sandstone, shale, limestone), that get muddy after being wet, and those that feel chalky.

Safe Rocks:
Crystalline Quartz
Microcrystalline Quartz
Quartz
Slate (fairly cheap and easy to find at home centers and pet stores)
Granite (rather abundant in a lot of areas, fairly cheap at home centers and pet stores)
Pumice (technically a glass, it usually floats and should not be heated to sterilize it since it can blow up)
Obsidian (technically a glass, often sharp, use with great caution due to the sharpness)
Lava rock (refer to pumice).


Unsafe Rocks:
Sandstone (some animals can tolerate it in the tank but it's better to be safe than sorry, avoid it as it can raise ph and water hardness and sometimes can contain "fool's gold" and other trace minerals, if you don't know the composition of the sandstone, don't use it)
Limestone (raises ph and water hardness, may contain iron pyrite)
Coal
Fool's Gold aka Iron Pyrite (lowers ph making conditions acidic and can also contain lead, copper, and zinc)
Amethyst (a type of quartz but what gives it its purple color, iron and manganese, is what can harm your fish/invertebrates)
Gypsum/Alabaster (is pretty much entirely calcium sulphate)
Marble (made of calcite)

For mineral/rock reference: 
http://www.minerals.net/

Correcting Previous Errors and Adding New Info on Fiddler Crabs

Steve

When i ventured into the world of fiddler crab care everything was new and i had searched far and wide for adequate information on their care.  While i found some sound information i also found some information that was less than ideal and some that was erroneous and i had posted some of that info my first blog post on fiddler care.  Not liking to be wrong but not liking to look like a dumbass either i must correct my errors for the good of the readers.

With experience i have learned quite a few things about the fiddlers and the first issue i must address is the misidentification of north american fiddler crabs sold in the pet trade.  Incorrectly identifying your north american fiddler likely won't interfere with how you care for it but it is important to know just which crabs you're caring for should you want to buy more of the same type. 

First things first, fiddler crabs fall under the genus of Uca.  The ones commonly captured and kept as pets in North America are part of the sub-genus minuca.  Uca pugilator (referred to as a sand fiddler), Uca pugnax (referred to as a marsh fiddler), and Uca minax (also referred to as a marsh fiddler but more commonly referred to as a red jointed fiddler) are common along the east coast of the US and are found as far north as Massachusetts.

With our first fiddler, Bob, i was unaware of the small differences between Uca pugnax and Uca minax.  Upon further research and closer inspection i can say now with confidence that Bob was in fact Uca minax, not Uca pugnax.  On the bright side, their care is the same.  They are similar in size and color (with uca minax getting a bit bigger with age) and are often found in the same habitats.

In captivity the red joints on the Uca minax may not be red, they might be orange or a ruddy brown.  No matter how hard we humans try we really cannot provide these animals with the adequate diet or space for them to be like they are in the wild, this can result in physical appearances that deviate a little from what is seen in wild fiddlers.  Often the crabs are transported in less than ideal and less than adequate conditions and will become "ill" during transport.  Being kept in freshwater conditions or (as wal-mart stores sell them) in little plastic dishes with barely any water can result in the crab having problems later on down the line.  Uca minax and Uca pugnax can both tolerate low salinity, but cannot molt or live long in a freshwater environment.  Uca minax can tolerate lower salinity than Uca pugnax.  Uca pugilator can tolerate higher salinity (reef aquarium levels even) as well as low salinity.  For minax, ideal salinity would be would be between 18 and 22 ppt.  Pugnax would do well between 20 and 28 ppt.  Pugilator can tolerate salinity up to 32 ppt, but with the fiddlers it is best to keep it under that.  32 ppt and beyond is reef salinity and brine salinity and fiddlers do not require those conditions and may not be able to come through a molt in such salinity.  Brine salinity is deadly to most fiddler crabs.  I've noticed that in my fiddlers, if the salinity rises due to water evaportion, they gain an orange color.  It is a natural response to rising salinity levels.  If you notice this issue in your crabs, test your salinity and reduce it if it reads high (past 28 ppt).

As time has progressed i have had 5 adult uca minax fiddlers.  Only one remains, his name is Steve and he is seen in the image above.  Bob passed away in early September 2014 from an unknown cause.  Bob lived alone in his tank, the salinity was great and the ph was perfect.  He had not been eating well for about a week and on his last day he had become sluggish and just wasn't himself.  He showed no outward signs of illness (no spots, no fungal growths, no missing limbs).  We figured it must have been age.  We had had him for 2 years and a couple months at that point. 
Both females i had passed away.  The first passed when i was ill in 2013 and unable to properly maintain the fiddler tanks.  Her name was Claudia and to this day i feel horrible because she passed due to my errors.  Our second female was murdered by Steve.  Her name was Fern, she was jolly and had a few egg sponges before the incident that caused her death.  I awoke one morning to Fern's molted shell and a dead Fern a few inches away near the filter.  She had a hole in her back and some of her claw tips were missing.  Steve had killed her and cannibalized her.  Then our most recent fiddler (purchased at wal-mart to save him from their negligence), Herb, we had for less than a month.  We purchased him at the beginning of January and he passed on a few days ago.  When we first brought him home he loved the tank, was eating good and was very active for the first couple of weeks.  Then he started slowing down, was hiding more.  We noticed his feeder claw had a strange black spot on it.  He was a young crab, his claw was small and he was about the size of a nickle.  There was hope he'd come out of whatever was wrong with him.  His condition deteriorated and he passed away.  After his death i did a bit of inspection, aside from the odd black spot on his feeder claw (which seemed to be part of the shell), he was missing a leg (which happened before we saw him at wal-mart but leg loss is usually not fatal in crabs), and on one of his leg joints there was a weird black spot in the tip joint.  The black spot made it impossible to bend the joint.  All his other legs bent just fine.  Just what these black spots were i don't know and it's incredibly difficult to find any information on fiddler crab diseases and disorders.  It's a mystery as to just what happened to him.  There's a little comfort in knowing he didn't die in the putrid centimeter of water in that awful wal-mart plastic dish, but due to his size i thought we'd have him for quite a while so his death was disappointing to say the least.

There's a myriad of problems these fiddlers can encounter in captivity.  Some of them we can control, most of them we cannot.  The problems we can prevent are chlorine/chloramine contamination, cyanobacteria (blue green algae) toxin contamination (occurs from overfeeding and too much light/sunlight after the bacteria has been introduced, which is usually by way of food), salinity issues, inadequate ph, ammonia contamination, and temperature changes.  Fiddlers are generally hardy little animals but they are arthropods and arthropods are sensitive to certain things other animals might not be sensitive to.  Avoid handling the fiddlers or putting your hands in the water if you just used soap, lotion, or hand sanitizer on your hands.

With some observation i discovered that fiddler crabs don't much care for loud music, it seems to scare them.  Fiddlers "hear" through the hairs on their body and some sound waves have negative effects on their behavior.  For that reason, it is wise to keep their aquarium away from loud noises and items such as TVs and stereos.

When i first started an aquarium with the fiddlers i thought they'd be fairly easy to care for.  In general they are.  What is difficult is when they die.  It's often for an unknown reason or may be the result of crab on crab violence.  With limited research existing for the public regarding diseases and disorders that may strike these animals, it leaves us humans with a lot of questions.

To any young people out there with a love for these creatures, please consider going into marine biology and specifically studying marine invertebrate diseases.  We need more scientists in the field.  So much is not yet understood about crabs and other marine animals, it would be a great benefit if more young people could pursue careers that would help these little creatures.

Hopefully i addressed all the errors i made previously.  Here's to hoping i didn't make any more in this post.  Further reading and information on the 3 most popular pet trade fiddler crabs in the US is below the picture of Herb.  There are also two links about hydrometers (one links directly to a hydrometer sale page). 

Herb (note the strange black spot on his feeder claw and then the strange black spot on the lower tip of his 2nd leg on the right side)

http://animaldiversity.org/accounts/Uca_minax/
http://animaldiversity.org/accounts/Uca_pugnax/
http://www.sms.si.edu/irlspec/Uca_pugila.htm
http://www.advancedaquarist.com/2002/1/chemistry
http://www.petsolutions.com/C/Aquarium-Hydrometers/I/Deep-Six-Hydrometer.aspx
http://www.geoexpro.com/articles/2012/04/marine-seismic-sources-part-xi-effect-of-seismic-on-crabs

Mr. Willers the Clown

The big fuzzy beast loves playing in the hose and then laying in the holes he digs and that's why he's a mess in the pictures.  A few updates on him are in order.  Willers is approaching his 3rd birthday and thus far he has had some joint issues, mostly due to him being a big, clumsy, crazy clown of a dog.  At some point last November he did something to his knee and hasn't been able to walk without a limp since yet still manages run around like a total nut.  We took him to the vet and he gave us some anti-inflammatory pills which worked for a while.  Our vet feared Willers may have a ligament issue that would require surgery if MRI results came back positive for what he thought may have occurred.  Since the pills worked though for a while he was fine and it seemed that what he did to his knee may not require surgery but we'll have to check with the vet again soon.  We believe he got this injury from jumping off one of the beds.  He also has an ongoing issue where he will land badly on his right front paw and the wrist will suffer the consequences but he usually recovers from that after a day or even just a few minutes depending.  He's a tall, gangly dog and that gets him into some pickles.  Anywhoo, aside from those two issues he's been doing well, quite well actually.  A couple months ago he pilfered a frozen raw turkey off the counter top, unwrapped it, ate it and left a small piece which we assume he left for the rest of us lol.  He's also pilfered pork chops and other raw meats from the counter tops.  We have to hide thawing meat in the oven or microwave these days.  What amazes us is that he can unwrap things very well.  Back in September he pilfered caramel apple lollipops one night and managed to unwrap them and the very bizarre thing was that he put the wrappers in one pile and the sticks in another and left 3 for the rest of us.  We don't have kids or anything and there were bits of lollipop everywhere so we know the dog did it.  Humans have a difficult time opening these things but that dog opened them perfectly.  He's a very smart dog and he uses those smarts for his evil plans to take over the world of food.  We love him though, the crazy oaf.  Life is more interesting when you have a crazy dog.

The Female Uca Pugnax Fiddler Crab

Usually when one thinks of fiddler crabs they think of the males who have one large claw and one small but we cannot forget to consider the females (without which there would be no males).  The female uca pugnax fiddler crab is an essential part of her brackish marsh ecosystem.  Females generally eat more and in a shorter amount of time thanks to having two small claws that are commonly called "feeder claws".  They clean the sand and mud of detritus and dead things, thus making for a cleaner marsh.  Males also clean the sand of such debris but they are hindered by their large claw and therefore do not consume as much in the same time frame as the females do.  Due to the male's large claw which is an unfortunate hindrance and burden, he is also more prone to predation than the females. 

The females are the carriers of the eggs.  Once a female becomes fertilized by a male she will form an egg band (which looks like a small dark sponge) on the underside of her carapace.  This band is very noticeable.  The eggs are attached with a sticky substance.  In the wild the females release the eggs into the tides after about two weeks of incubation.  The eggs then hatch in the ocean and the baby crabs (also called larvae) become part of the zooplankton population.  Females can mate roughly every 4 weeks during spring and summer (and in captivity into later autumn, possibly even in to winter if the water temperature remains above 70 degrees Fahrenheit--this is a personal observation).  I must note that i have witnessed my female crab Fern eating the eggs off of her after they've been present for 2 weeks.  I am not 100% sure but that seems like a normal behavior that would occur if the female were not able to dispatch the eggs into the ocean.  I have also noticed that after each egg cycle she moults.

Fern, Female Uca Pugnax Fiddler Crab with Egg Sponge

Uca Pugnax females are burrowers and in the wild use those burrows to reside in while they are incubating (waiting for embryonic development) their eggs.  In captivity however the female may not be able to make a burrow so she may hide in an aquarium ornament or if she's not threatened by her tank mates, she may not hide at all.  Fern is not one to hide while she's carrying eggs and very much enjoys being out and about. She also enjoys staring at Bob in the other tank. I do feel Fern has a liking for Bob, it's a pity Bob is a jerk and cannot live with Fern and Steve.

Female crabs can be very social with other females and males but sometimes disputes do arise and females can become aggressive with both sexes.  Though it is somewhat rare for the females to get into altercations with males, it is not so rare for females to get a bit rowdy with other females.  Such disputes usually occur over territory and burrow/aquarium ornament rights but they usually don't involve injury.

While similar to the males, the females do have some differences.  If one observes the underbelly of the female they will see her carapace looks different than a male's.  There are also the obvious claw differences and sometimes the males will be darker or brighter in colour than the females.  In the aquarium setting females are more likely to escape because their climbing skills are a little better than the males' because the females do not have the hindrance of the large claw.

Fern attempting to climb the filter and aquarium wall

Fern side view (looking into Bob's tank)