Rearing metamorphs

A long time ago I noticed that if I provided them with little to no land area and fed them only in the water C. cyanureus would come out of the water for a very short period of time and then basically revert to an aquatic lifestyle. (they would also morph at a larger size, occasionally as large as an adult C. orientalis) As a result of this the larva would grow extremely rapidly and reach reproductive age within about a year.
After reading Sparreboom's articles on rearing this genus, I noticed that he pointed out that if you set them up like I had the cyanureus you could rear the larva aquatically so I decided to try this with a different species, C. pyrrogaster (of which Jen was kind enough to send me some eggs). This species is easy to rear to metamorphosis but metamorps at a small size when it becomes more labor intensive to care for resulting in most people only rearing small numbers. I took the batch of eggs (which was probably about 30 eggs) and set them up in a larger rubbermaid container with a 12/12 photoperiod. Post hatching the larva were fed on chopped blackworms (and I suspect there was some cannibalism but I did not actually note any) daily. Larval growth was rapid and the larva metamorphed. Again I provided some haul out spots via floating plants (in this case Java moss) and provided no food to the larva above the surface. After two weeks the first larva began to feed underwater and all but 4 (out of 20 metamorphs) were feeding underwater on chopped blackworms. These four held out until they were noticiably skinny before converting to aquatic feeding and as a result were much smaller than the others requiring them to be seperated into another container. The metamorphs do not stay in the water all of the time and appear to submerge and feed and then come back out of the water. The growth rate on these is to my memory less than that of cyanureus but is more than what I anecdotally remember from trying to rear them conventially on land. Even if it is initially less the resulting lessing of labor in rearing the metamorphs should make more than make up for any slower growth periods.

I suspect that this may be an adaptation for the metamorphs who move onto land and are unable to find food or a habitable niche.

Ed

As a postscript in a moment of carelessness I lost most of the metamorphs by forgetting to make sure the lid was tight when I wasn't going to be home for several days and the majority of the metamorphs escaped and were not recovered.
At some future date, I would like to rear two batches side by side to see if the growth rates are different and not just my wishing.

Ed

thanks ed, one question-what temps you do this at with the pyrro's?

I have found that the willingness of Cynops morphs to stay aquatic depends on:
1. Lower temperatures
2. Still water - even a gently bubbling filter tends to make them more terrestrial.
I like to raise them as Ed describes, plastic box crammed with plant. Simplicity itself.

alan, so you say low temps slow morphing? i have had it do that but unfortunately post morphing the low temps seem to cause them not to eat well-do you tweek up the temps post morph?

Well, yes, lower temps will slow morphing. IMO this is advantageous as they morph at a larger size.
However, What I meant was that they are more likely to be aquatic at lower temps, terrestrial at higher temps. When I say lower temps here, I'm referring to less than 20C, not very cold. At average "room temperature", e.g. 25C, they don't want to stay in the water and start climbing the glass.

the temperature in my basement is usually between 65 and 74 F (18-23C) but it fluctuates up and down a little outside of those ranges based on outside temps. (I expect it to get about 76 F in later August but if it doesn't I may actually have to "heat" my tylos enclosure to stimulate breeding.

Ed

Thanks for the writeup, Ed. Based on my experience last year, I gave up on trying to raise C. pyrrhogaster in water. It's good to know that it can be done. Maybe I should try again with more java moss. This year I'm keeping them terrestrial with fruit flies, whiteworms, and small cut-up earthworms, and they are growing surprisingly well. I'll be posting some photos shortly.

My experience with ensicauda and cyanurus has been quite different. They have done well for me semi-aquatically.

Nice report Ed, Alan, Jen.
Most of my last years (cynops orientalis) morfs are still on land are very time consuming to feed. This year I'm rearing some in a similar setup as you describe, but at room temperature. By adding duckweed in the water I can see when they have been in and out of the water

No skinny morfs here. They started eating underwater within days. However they spend most of the day on (wet) land.

I also noticed that my last years morfs are more willing to head into the water when I refresh it with <u>cooler</u> water. So that also seems to confirm your findings.

Joeri

Inspired by Jen; here's a picture of this years morfs and one of their setup (a plastic box with moss, duckweed and a few plastic leaves that stick out of the water as well - the island is moss on a stone)

Here are some pictures of recently metamorphed cynops in the water feeding (they did not like the camera flash).

Ed

Ed/Joeri:

What water depth are you guys using for these aquatic setups? It looks like enough to totally submerge the morphs? IME it seems that right before morphing Cynops orientalis are very prone to drowning(even in quite shallow water). Does letting them out onto land temporarily solve that problem?

(Message edited by fishkeeper on August 22, 2005)

Hi Joseph,

They can get out of the water if they choose by climbing on the emergent moss mats but I do keep the water deep enough for them to totally submerge. The water in that shot is about 2.5 cms deep. I have not tried this with orientalis as of yet but the literature does indicate that it can be done with that species as well.

Ed

My water is about 2cm deep. They can climb out the water very easy using moss as well. But I have to admit that last week a morf died. It had morfed some weeks ago. I think it drowned. The others are still doing fine.

Ed, I love that red stripe on their back. Is it as bright as in the pictures or is that because of the flash?

No the stripe is really that bright and is not just an artifact of the flash.

Ed

very nice pictures, i am going to try this rearing method with my next batch of c.o. the female looks like she is about to start producing eggs.

Here is a updated picture to give an idea of the amount of growth that has occurred in the last several weeks.

Ed




<font size="-2">(Ed, I added a space between the photos ;) -- Tim)</font>


(Message edited by TJ on September 01, 2005)

Looks like they doubled in size!
At least they became twice as fat

Looking good Ed!

they have indeed almost doubled in size.

Ed

[Duncan]

Hi All,
I've been raising my C.e.popei in pretty much the same way as Ed. Here's my setup and a few of the current residents. The ones that stay (and feed) more frequently in the water definitely seem to be growing faster. These are by far my most colorful juveniles that have hatched out, I can't wait to see what they look like as adults.
Duncan

One word... WOW!
Good job Duncan