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Do they normally turn blue after a while????

After the last two molts he's a new striking blue.



Is this normall? Or am I lucky?


Angel EEl

I read about this happening a long, long time ago, so I know that it is not totally unusual, though I couldn't tell you why it happens.

Hoping that there must be a word for everything I mean...

ANyone know why it happens??????



ANgel EEl

A few bits of info I found in a search and asking people:

A crayfish's colour is in part influenced by the colour of the water. As the animal grows, it sheds its hard exoskeleton and produces a larger one. At each moult, the colour of the new exoskeleton will be influenced by the water colour. Muddied waters can produce darker crayfish, whilst blue and clear water can help produce the popular brilliant and iridescent blues and whites.

Maybe they are changing color from the water in the place where you are keeping them. Wild crawdads are that red color for camouflage. When we catch baby crawdads and keep them in an aquarium tank, they grow up to be blue. I suppose that if the water was that dark color that is in the pond we catch them from they might change back to red....just a possibility.

Typically there are two types of blue crayfish. One that is genetically blue and one that has a blue color because it is missing something from its diet. If you have a genetically blue animal it will not change color over time, but if you have an animal that is blue do to nutrition, it may eventually molt back to its normal color once it begins getting the right things in its diet. Some breeders know these things and probably sell them to stores knowing that they are not truly genetically blue animals.

Sham, can you quote your source and/or provide a link please?


It'll be environmental. You can get them to turn white if you keep them in a milky coloured water (experiment done by a company that produces cray for restaurants)

For animals, the entire universe has been neatly divided into things to (a) mate with, (b) eat, (c) run away from, and (d) rocks. - Terry Pratchett

Really??
So is my cray blue from bad diet or from the water????


:%)


I think he has a fantastic diet, live fish, shrimp pellets, flake bloodworms....so for some reason I don't think thats it..


That was a good peice, Where is it from?


Thanks
Angel Eel

I strongly suspect that some shrimp change colour according to heat and diet too, ive had armored fan shrimp change from blue to pink and vice versa, and the light in the tank is totally consistant. The one that stays primarily blue does a lot of scavenging of missed fish food, and the primarily pink one eats mostly brineshrimp.

Certainly a lot of shrimp can match their colour to match surroundings, often marine types such as those that inhabit nudibranchs can come up with perfect colour matches , although I think freshwater species are typically less able to do this.

Last edited by longhairedgit at 02-Sep-2005 21:39