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.