30 Dec 2008

Lazarus (Shrimp) in Israel?

Dear Blue Lobster:

I am getting ready to start growing triops with the kids.

Are you aware whether there are fossils of triops in Israel? Where could I go with the kids to see them?

Thank you,

Nathan Wirtschafter
Hashmonaim, Israel

23 Dec 2008

Will My Ten-Incher Get Bigger?

Dear Blue Lobster:

I bought a blue lobster from WalMart about 3 years ago. He is now about 10 inches long (tail to claw) and still growing. How big do these get?

Bill Schamp

Dear Gentle Sir:

Without knowing the species, it is hard to say. Typically, there are only two species sold at retail chains in North America: Orconectes immunis, which reaches around 14cm (5½ in.) or Procambarus alleni, which grows slightly largers at 15cm (6 in.). Since your cray is roughly twice the length, it is possible that it's an Australian variety, as Australian species often exhibit insular gigantism. Whether it's a Cherax destructor, fabulosis, quadricarinatus, or tenuimanus, or another less common species, it could easily grow upwards of 34.5cm (13½ in.).

Since your cray is quite large and will likely grow larger, you should have a twenty gallon tank at a minimum, if not twice that. Considering the better conditions the cray will recieve in your tank, and the possibility that there are growth-inducing chemicals present in the water itself (from birth control pills, industrial runoff, etc.), your cray would be safest in a one hundred gallon tank. This would allow him or her to grow to an impressive 45cm (almost 18 inches!) and still feel unstifled. You can also create quite the reproduction of a natural environment with the extra room, including logs, rocks, shallows, and substantial flora.

In the future, when asking for help regarding a specific cray, include some documentation that might help identification. This includes some photographs from different angles, especially the cray's underside, place and date of purchase, and the common or scientific names and any other information given at the store. One may be able to deduce from some of the less direct evidence what family or genus the cray is, if not the species. This can help make any advice regarding your cray more accurate and therefore more beneficial in the care of your little crustacean friend.

16 Dec 2008

The Case of the Colorized Cray

Dear Blue Lobster:

We have an Electric Blue Lobster. He's gone through at least two molts and is if anything a much richer, deeper blue (with bright red spots in places). Does this mean he has not been artificially injected with blue dye?


Dear Gentle Sir:

Though cray owners usually complain of the opposite—their cray's colors fading into disturbing shades of slimy brown-green-grey, factors that don't include unnatural dyes or make-up can cause a cray's colors to become brighter and more pronounced.

Lighting is important. Despite being a bottom-dweller, crayfish are used to and require regular doses of sunlight throughout the year. Without this exposure, they fail to form vitamin D and other compounds necessary for robust health. With crayfish, poor health means poor color.

Your substrate can also affect your cray's coloration. Like any animal, the cray will try to blend in with its surroundings, and like some specific animals, the cray can change its coloration. If your gravel is bright, your cray is likely to become brighter over the course of several molts.

During some species' mating phase, the cray may ingest local minerals or plants to augment their look. This serves to make the cray more attractive with specific muds causing reds, blues, or yellows come out in their shell. Some species even wear algae or fungi as wigs.

Keeping a picture journal of your cray can help document its color changes. Whenever you perceive a coloration change, use your favorite webcam to take pictures. Then upload the pictures using your favorite blogging software and you can over time adjudge the what, if any, change has occurred.

22 Apr 2008

Black Market Crustacea

Dear Blue Lobster:

I was reading your web page when I came across a really neat marine shrimp, Lysmata cyanea. I figured that you might know someone that works with this particular species of shrimp or where they originate. Would you be able to help me in acquiring some specimens? Any help with this would be greatly appreciated.

Best Regards,

Dear Gentle Sir:

Many species highlighted in academic research are not part of commercial trade. These species are often rare or endangered or, in the case of new discoveries, not classified or surveyed yet. In other words, there's no commercial access to such species that are so well outside commercial aquarium trade.

That isn't to say there's no way at all to obtain specimens, however.

There is a thriving underground black market for rare and valuable crustaceans driven mostly by private collectors but also fueled in part by academia and museums: unscrupulous collectors and curators and university students, faculty, and staff. In Africa, for instance, importing O. rusticus is quite lucrative as the return on successful aquaculture in Africa is estimated to be worth hundreds of millions of euros annually, small change in comparison to other markets, but huge in the scope of source of the specimens.

The sad part about students mixing up with the seedy underbelly of animal trade is that both people and crustaceans die needlessly. Recently, pirates murdered the crew of a ship carrying several tons of O. rusticus; eight are known dead and two are missing. Last June, the crew of a trawler secretly hauling Diamond crabs were killed after engaging in a gunfight with the West African Coast Guard.

Ultimately, such disregard for animal life goes against the tenets of research and objectifying specimens leads to a loss of knowledge and endangerment of those involved, whether they are foolish undergraduates or sunburned pirates. Do not support this illicit trade and instead report it to your local authorities. If an animal is unfamiliar enough to remain outside the aquarium trade, leave it that way.

15 Apr 2008

Why Did My Fiddler Crab Die?

Dear Blue Lobster:

We volunteered to take the Fiddler Crab from my son’s in-class science project. The crab appeared to be doing well, eating and taking some dips in his “pool” of salt water. We changed his water and his food regularly. He burrowed through the substrate mixture (sand and humus?) in the bottom of his cage – and often slept under his see-through pool (the container the class used to provide salt water).

He was more lively than usual over the weekend – climbing up and over the flat seashell, ½ coconut shell, fake plant, and swimming pool.

Today, he appears liveless – he is upside down in his cage and has not moved since we woke up this am. There doesn’t appear to be any new appendages or a new crab anywhere in the cage.

Can you tell me how to tell if he is dead, molting, or already molted?

This mom is unfamiliar with fiddler crabs and wants to make sure we know what “Thunder” is doing, before assuming him dead.

Thank you.
Linda Adams

Dear Gentle Sir:

Thunder, from your description, appeaears to be dead. I am so sorry for your loss.

A crustacean's living conditions general health affect its ability to molt. Sick or otherwise unwell crustaceans molt abnormally and may not molt at all, and if a crustacean can not molt when it needs to, it will die.

When an illness or stressful situation limits the crustacean from molting, it will literally explode in its shell. The cracks induce sepsis from the numerous infectious agents now able to attack the soft inner body.

In Thunder's case, it appears that his living conditions were suitable generally and he was in more or less robust health, so what other factors might have been at play?

It is possible that, despite Thunder's well-kept tank, the stress from too many visitors kept him feeling unprepared for a molt. Did one of his numerous visitors offer him something potentially poisoinous?

One must keep in mind that Thunder might have been nearing the limits of his lifespan. You don't mention a physical description, but most Fiddlers live no more than two or three years. One species, Uca senex, lives to be seven years old in some cases, but that is an exception to the norm.

It is possible Thunder had scuttled through the greater part of his life when you inherited him, and either his own old age or the stresses of students and moving to your residence finally knocked him off.

One must not blame onesself for such tragedies, however; only in dealing face-front with crustacean rearing and death does experience build. Check out some crustacean or aquarium literature from your local library and consider your time with Thunder. The next little friend you take in will benefit.

8 Apr 2008

Sudden Crustacean Death Syndrome

Dear Blue Lobster:

We purchased "Pinchy", an electric blue lobster about 7 months ago from a local fish shop.

He has been extremely healthy as far as I can see, always eating, molted about every 60 days, great colour, very active in the tank torturing our other fish. Tank is 90 gallons, pH about 6.5, temp about 76 degrees.

Last night "Pinchy" was alive and well, cruising around the tank looking for treats. This morning "Pinchy" was dead, lying on the bottom, no signs of struggle. Water is fine in the tank, nothing is broken, nothing else is dead, the other fish had not even touched him yet.

What is the average lifespan for this type of lobster? Also, anything off the top of your head that you think he may have "caught" disease-wise? It just blows my mind that he died for apparently no reason.

Looking forward to hearing your opinion,
Brett MacLean

Dear Gentle Sir:

There is nothing more shocking than seeing your perfectly healthy little friend lying belly-up at the bottom of the tank, legs gently swaying in the current. It is this kind of unexpected, unsymptomed death in otherwise healthy individuals that is called Sudden Crustacean Death Syndrome, or Scruds for short.

As with any syndrome, Scruds describes related symptoms but not the underlying cause. In your case, Pinchy may have had several conditions, including a bacterial infection, a congenital neural disorder, or chronic aging.

The possibility of a bacterial infection here seems minimal since you describe Pinchy as being healthy and active, though sepsis-related Scruds of healthy individuals is not unheard of. It also doesn't sound like you are unfamiliar with aquarium maintenance so the possibility of a bad water change, temperature shock, or chemical poisoning seem likely.

In the case of a neurological disorder, the defect is inborn and there is no real way to prevent its onset. Crayfish family histories are so hard to track outside of a lab that buying an animal commercially is a crapshoot as far as genetic health goes. If this was the case with Pinchy, a shift in water temperature, introduction of a specific bacteria, or an slight shift in chemicals or other factors could have caused his nervous system to short circuit.

The most likely explanation for victims of Scrubs remains, however, is chronic aging. Chronic aging is a perennial issue with any life-based organism, as complex systems wear out over time due to the degradation of DNA during the replication process. You didn't mention how old your crayfish was, only that you'd had it for seven months.

Species typically sold as "Blue Lobsters" (see the end of this entry) typically live from two to four years with some captive specimens living five or six years. One notable case, a specimen named Methuselah, lived to be an astounding ten years of age and only died when an undergraduate lab tech cooked and ate him.

Size is the key to your cray's age. Anything beyond four inches is a good indicator that the cray is at least middle-aged and one can only hope for a few sweet months and expect to get them. This is one reason why buying younger crays is a good idea as you get more cray for your money; that is, until a treatment or cure for chronic aging is discovered.

11 Mar 2008

Not So True Blue Two

Dear Blue Lobster:

Recently I bought a blue yabbie and a electric blue. I know electric blue lobsters are usually many different breeds all thrown into the same name but I have one that's exhibiting really odd coloring. He looks like the standard blue at 6 inches or so except his last molt he developed bright orange almost see through sides to his claws, the part that's stationary not on a joint.

One more thing, my blue yabbie was very brown except for his claws when i purchased him, after 5 molts he seems to be slightly turning blue and developing red spots along his tail but I'm worried if he will ever turn the bright blue or dark black I see from others pictures, and if so, how long should I expect?

Its amazing looking but I was hoping you could tell me the reason behind this. From your last posts I gather it may possibly be mating colors.

Thank you tremendously for your time and please keep up your highly informative blog.

Matthew McMullen.

Dear Gentle Sir:

Your guess of mating colors is a good one, though it's hard to tell what species you're working with as there are at least a dozen species with blue morphs; there are likely three or four times as many that just haven't been documented properly yet. One is lucky to see even the label "crayfish" at pet stores.

As to why the drastic change in color has happened so recently, another factor might be at play aside from mating colors. When cohabiting different species, mating colors can mean that the two species are attempting to intimidate one another in order to establish dominance. Since their tankmate's body shape and language aren't as expected, mating colors are a surefire way to show off.

There's no telling what direction their color changes might take unless you were able to identify what species they were; likewise their mating morphs might prove helpful in doing so.

As for worrying about the crays color changes, I would instead recommend that you sit back and watch the fireworks. Animal adaptability is a wonderful phenomenon to watch and, so long as your crays are not violent with one another, you might as well marvel at their chromatic displays.

For the record, species known to have blue color morphs include Cambarus diogenes, gentryi, and monogalensis; Cherax destructor, quadricarinatus, and tenuimanus; Orconectes immunis and obscurus; Pacificastus leniusculus; and Procambarus acutus, alleni, and clarkii.

4 Mar 2008

Freeze-Dried Fiddler Food

Dear Blue Lobster:

We just brought home 3 freshwater crabs from the pet store and my kids LOVE them, we would really like to take good care of them. The pet store sent home Freeze dried pellets for them and I am desperately looking on the web to see if these are appropriate for them to eat, or what the best food for these liitle guys is. Can you help? Also what kind of healthy behavior should we expect from Ashlyn, Cherry and Galatian?(the crabs not my kids:)


Dear Gentle Sir:

Freeze-dried pellets, while not optimal, are just fine for your crabs to eat. They are composed primrily of fish and shellfish offal and sometimes farm runoff as well and so provide nutrients however dried and pressed they might be. Live foods are usually superior because they are not processed and stored, both of which degenerate nutrients. Live foods are also not susceptible to the underhanded practices of big business.

In 1993, the aquarium industry was hit with a wave of strange deaths; thousands of vertebrates and invertebrates alike acted sluggish, then died. Over the course of several weeks animal death climbed some 15% above normal rates and eventually the Foodeaze line of pellets, from the now-defunct Fisheaze company, were blamed.

Investors and aquarium trade companies filed suit against Fisheaze and during the course of the trial the details became horrifyingly clear: Fisheaze had been buying and using not just fish, pork, and horse offal but also manure and farm sewage for their pellet lines, something clearly against industry regulation. The manure contained strains of deadly bacteria that, upon entering water, reactivated. It was like an aquarium Plague.

By the end of the trial, Fisheaze was required to pay out some $2 billion to the industry, the largest such judgement at the time. Perhaps the most disturbing result of this mess was that Fisheaze had invested in several fish farms where the animals were intended for human consumption and was supplying the farms with feed; the Department of Agriculture began investigations into the company before the folded in 1998.

Though nothing like this has since happened, it boldly underlines the importance of knowing the food you give to your crustacean friends comes from a trusted source. Fresh food is not only healthier but generally safer as well, since the responsibility is directly on you and not some process stretched out over thousands of people and tens of thousands of miles.

19 Feb 2008

Glow-in-the-Dark Yabbies

Dear Blue Lobster:

My red claw molted last night and came out with white spots on legs and claws as well as a white bad across the tail at a joint. I am wondering if this might be the white spot fungus (possibly caught from the feeder shrimp I buy at the local pet store).

Yabbie is about 3years old now. He lives in a tank with a few other small fish. I guy glass shrimp and sea monkeys once a month or so. I was just wondering if there was anything I could do to help him, or if it’s just a sign of his age.

Thank you!


Dear Gentle Sir:

Unlike your grandfather, shrimp do not get spots as they age. This is plainly a sign of infection, though what your shrimp is infected with is debatable without seeing him in person. If the disease came from the feeder shrimp you purchased it's most likely a fungus, possibly Topicalis albinus, better known as White Spot Disease.

At the time of that article, however, I stated that tetracycline would be ineffective since it only treats bacterial, not fungal, infections. New research (Giles 2007) suggests that tetracycline does indeed have efficacy against albinus, though the mechanism isn't yet understood. Tetracycline is a safer possible solution to White Spot than copper, which is hazardous to invertebrates.

To administer the tetracycline, simply grind the pills using a pill grinder and mix the powder in distilled water, adding one drop a day to your aquarium using an eyedropper. If your cray has holes in his shell from his infection you might want to inquire about Actisite, a thread-like fibrous form of the drug usually used in dentistry; it make have similar applications for crustacean shells.

Though tetracycline is generally safe, one side-effect is that it causes keratin, found in bones and hair, and chitin, found in arthropod shells, to glow under UV light. This isn't a negative, however, as adding a UV to an aquarium is cheap and you and your family could become the envy of the neighborhood with your glow-in-the-dark yabbie.

5 Feb 2008

Marmorkrebs: Das Klonen Kräfisch

Dear Blue Lobster:

I had an arthropod physiology class and in it we discussed Marmokrebs, a crayfish that clones itself. Apparently it is taking over fresh and brackish water systems in Germany and there is fear that it will overrrun Europe unless a way is found to stop it. How is it possible there is a cloning crayfish? I am curious about this topic, many thanks for answering my query.

Warmest Regards,

Dear Gentle Sir:

This crayfish species, named for its marbled shell, has raised debate in astacology recently, as each and every specimen of Marmorkrebs is molecularly identical; that is, each Marmorkrebs is a clone. Its origins are just as mysterious as its genetic pool, with Marmorkrebs only discovered in the Nineties. It still lacks a scientific name until it can be placed within a genus.

Marmorkrebs reproduces in three unique ways, setting it apart from not only other crayfish but all other crustaceans as well. On a regular cycle it goes in berry, holding a clutch of up to one thousand eggs for just over two weeks. The eggs are fertilized although there is no male contact — all Marmorkrebs are also female. The eggs then hatch and the craybies grow just as any other crayfish young.

The Marmorkrebs also buds, where during a series of several molts in the Summer months extra body parts grow and, at the end of the cycle, a completely new Marmorkrebs splits off and lives indepdenently of the original organism. This is a method employed by simpler organisms, including several classes of worms, sponges, and hydras as well as microorganisms like bacteria and fungi.

Analysis of Marmorkrebs DNA reveals several sequences, particularly in genes controlling reproduction, that are unique among Animalia. Research continues in placing Marmorkrebs within crayfish taxonomy, with one Dutch researcher commenting that the DNA is unusual for a crayfish, let alone an arthropod.

Further study will unlock the secrets of this exotic, mysterious new species. In the meantime most Western countries have placed a moratorium on the shipping or sale of the species due to its potential as a nuisance species, though China is investigating it as a cheap foodstuff.

8 Jan 2008

Cray vs. Frog

Dear Blue Lobster:

We have an electric blue crawfish and our frog try'd to eat it! What do we do?????!!??????~~~!@!!!!


Dear Gentle Sir:

This is serious business. Crustaceans and amphibians are natural sworn enemies, each trying to devour the other at any given opportunity since the beginning of their lineages. This started in the Devonion, when pisciforms first began their incursions on land, shallow pool-dwelling crustaceans being an abundant and natural prey. Since then, crustacean and amphibian evolution has been an arms race in which each side develops defenses against the other.

In your case, you likely have an odd pair. Most crays in aquariums are either species native to the Americas or the owner's locale, while most aquarium frogs are from Africa, which lacks native crayfish species; the two species in your tank have not encountered one another in millions of years. In this clash your frog and cray are both agressing against one another in order to establish either dominance or dinner.

For your cray's sake, separate them until they are roughly of equal size. Once neither has a clear advantage over the other, they will keep to themselves. You can achieve this by either using separate tanks or installing a tank divider, a cheap solution available at any pet store.

1 Jan 2008

Bloop: A Crustacean Phenomenon?

Dear Blue Lobster:

do you know anything about bloop? i learned that it was a sound that the government recorded and that it's from a living creature, but i don't know any more than that. it happened in the ocean near south america, so i figured since you spend time down there you'd know.


Dear Gentle Sir:

Bloop was recorded in 1997 not by the United States Navy but instead by the National Oceanic and Atmospheric Administration, a spying front for the United States military. Originating near 50º S 100º W, some 1,500 kilometres from the Republic of Chile, the sound was recorded by SONAR equipment more than 5,000 kilometres apart. Though researched by both academic and military specialists, no consensus was reached regarding the sound's origin.

A few facts about Bloop were disclosed that continue to intrigue the scientific community. One is that the frequency was outside the range of seismic and volcanic activity. It was, however, within the frequency that biological organisms create. The puzzler there is that the sound was so powerful no living creature, including Blue Whales or the largest known Giant and Colossal Squids, could have produced it.

To produce a sound strong enough to be heard across 5,000 kilometres of ocean at depths averaging four kilometres, the sound would have had to originate at roughly 300dB, loud enough to cause violent hemorrhaging, disorientation, and death in humans. To generate such a powerful sound, the creature would require a body mass of about 200 square meters, larger than even a Blue Whale.

There are few candidates to explain such a creature. The possibility of it being an unknown species of whale is slim, as whales must surface to breathe and an animal one and a half times the size of a Blue Whale would surely have been recorded. Theories about Bloop being a Giant Squid species or the Colossal Squid are without merit, as the largest of either species falls well below the required size and cephalopods also lack organs for generating sound.

One theory that does hold merit is that the creature is a gigantic crustacean. Lobsters and crabs "burp" bubbles of carbon dioxide gas from their gills and often retain the air to belch at other species and to impress potential mates. Comparing the Bloop sound profile to crustacean belches nets the most similarities despite obvious difference in strength.

Should Bloop have been a giant, heretofore unknown crustacean species, it would explain the similarity of the sound to crustacean burping. A crustacean at such depths would need a shell a foot or more thick to protect it from the crushing weight of the ocean, would grow incredibly slowly, and would be part of a breeding population of perhaps just a few dozen individuals.

Oceanographers and acousticians are currently examining new sounds recorded by the USNOAA, including Glop, Blorp, and Poot, that all have similar signatures in hopes of discovering the source of these enigmatic deep-ocean sounds.