Crayfish Journal (Cambarellus Patzcuarensis sp. Orange)

Update with pics!

Batch 3 and 4 are doing well together in one breeder net. Because they were both born so close to each other (around less than a week apart), I was able to place both batches into one net without fear of the older ones attacking the newborns. I've been feeding them frozen bloodworms and some crushed snails. Mainly frozen bloodworms this time, I ran out of snails that were easy to crush. I have lots of MTS to crush but they have super hard shells and not much meat. Not worth my time >_>... anyone local wanna dump a ton of pond snails and ramshorn snails to me? :evil_lol:

Anyway, the bigger baby crays are growing fast! After I moved them into the tank, the extra space really helps them grow craaazy. So for people who are raising young, once they hit a decent size (around 1/4 inch with a stocky carapace), set them free to be with the parents. It should be safe by then for them to be not seen as free food. They grow MUCH faster once they are in a bigger environment. That's normal for all things though :) More room = faster growth.

Picture with my pinky is to show size. Of course, my pinky is closer to the camera, thus making it look much bigger than the cray... it's a rough estimate, so bare with me. The crays were right next to the glass when I took the pictures though. I also have a picture of the large female + her niece and nephews. This female was the smaller one of the two that I had and her original batch, batch #1 and #2 didn't really do too well because I left them in the tank with the parents. Her 3rd batch is now in a breeder net, along with female #2's (who is now dead) second batch. There's a ton in the breeder net (picture 1 and 2 represent first half of the net and the second half of the net) :-) The pictures make it hard to see though, because there's some old frozen bloodworms in there that turned clear so it kinda camouflages the babies who are still clearish with a slight tint of orange.

Anyway, without further ado, pictures!

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Well, if people have read up to date with the journal, then you may have come across the part where I said my single male died. And at that point, I was just waiting for one of his sons to grow up a bit more to impregnate his mother. (Oooooh, that's so nasty...)

In any case, today was that day. Now, the batch from 3/20/09 are still in various sizes. Some are noticeably bigger, others are still fairly small compared to the larger siblings. But, this does mark a day in when a crayfish can hit sexual maturity, for a male cray anyway.

Today is 5/26/09 and birth date was 3/20/09. So this means, it took 67 days for my leading adult male to hit sexual maturity. That's about 2 months!

Please note that many factors come into play.
For one, at an early age, they were kept in a breeder net. A safe place for them to be from parents but it IS confined. Therefore, a small room to grow = slower growth rate. Second, I fed crushed snails almost daily to enhance growth speed due to more food intake. I did skimp out a few days here and there though.

I did note that when I released them from the breeder nets, they grew at an incredible pace. I would think it is safe to assume that like all things, the bigger the room they have to grow, the faster they can grow. The faster they grow, the faster they can hit sexual maturity.


SUMMARY: It takes a little over 2 months to hit sexual maturity for CPOs. Or at least, for my crays anyway!
 
Wow,

thank you for this VERY informative thread and excellent pictures! You're right - this was very much needed. I'd read that with crays (I have cajun dwarf ones) the young would cannibalize each other during molts. But it seems (at least, with CPO's) that you've shown it is really the adults who kill off the majority.

Each time you were putting a bunch of the babies in together in the breeder net, I kept thinking "uh oh", and that they would prey on each other. Did you see that at all? Or I'm wondering did you provide lots of hiding places, and just lift the moss out at picture time?

The picture with several juveniles in your large tank is really impressive. I'm curious if you've seen any territorial behavior emerging. You said your male would display at you when you looked in, so I'm wondering if the newly mature male is showing this behavior as well.

Could you re-cap a few things, please?

You said the size difference between batches of hatchlings was very important, but you put some together from two batches that seemed safe together - how many days apart were they? And what would you suggest as the cut-off point for combining or not combining groups?

And how long did you leave them in the breeder net before putting them back into the larger tank with the adults? Did you put them in one by one as they reached a larger size, or decide that the whole group could be added to the tank?

This is really a great thread to see the process in such detail. A huge Thank You!
-Jane
 
Wow,

thank you for this VERY informative thread and excellent pictures! You're right - this was very much needed. I'd read that with crays (I have cajun dwarf ones) the young would cannibalize each other during molts. But it seems (at least, with CPO's) that you've shown it is really the adults who kill off the majority.

Each time you were putting a bunch of the babies in together in the breeder net, I kept thinking "uh oh", and that they would prey on each other. Did you see that at all? Or I'm wondering did you provide lots of hiding places, and just lift the moss out at picture time?
I did see them fight over dead snails when I dropped them in. Some would run around the snail and push everyone back. Then go to the snail and start eating it. His/Her siblings didn't really care though and charged right up at the snail as soon as the "defender" was busy eating. I witnessed mock fights but they're simply too young to kill each other. I witnessed none of that while they were in the breeder net, nor did I see any after I released them.
As for hiding spots, I don't think it's as important as people say. At least, not in my experience. As long as your babies are well-fed, they won't attack each other to cannibalize. They'll mock fight but they jump away after a second or two. The moss (actually, it's small pcs of moss covered in algae, LOL!) you see in the picture is pretty much all that's in there. I do not add any more. I did not lift anything up for the picture, I didn't want to get my hands dirty. Hahaha! But the logic to the whole cannibalism thing is simple. If you leave a baby crayfish hungry, they will have to fend for themselves and run around looking for food. When they run around looking for food to hunt. In order to prevent this hunting behavior, feed them! Lots! They'll be nicer to each other with a full stomach. Even then, this is only a theory. I have never seen my crays attacked each other to the death. Even when I left them hungry for a couple of days.
The picture with several juveniles in your large tank is really impressive. I'm curious if you've seen any territorial behavior emerging. You said your male would display at you when you looked in, so I'm wondering if the newly mature male is showing this behavior as well.
At the moment, I have not seen any of my new males acting the same way as my old male. Crays develop their own personality overtime. That male cray was just simply more daring than these I assume. Or perhaps time will help them develop a change in personality. I do not think all crays carry the same personality traits of being aggressive/daring.

Could you re-cap a few things, please?

You said the size difference between batches of hatchlings was very important, but you put some together from two batches that seemed safe together - how many days apart were they? And what would you suggest as the cut-off point for combining or not combining groups?
It was only 2-3 days apart, if my memory serves me right. Size difference must be BARELY noticeable if you are going to keep them together. It's hard to say what measurements to use because they're so tiny. So just make sure that they're under 1 week apart, and you should do okay. Feeding is important! They die without daily feeding. I neglected to feed mine for a few days because I ran out of snails and I experienced a big loss in my net. I cared more about my new hino CRS' newly cycled tank and I ended up neglecting the babies in the net. Out of 30+, I ended up with about 20. Sold a handful and gave a couple a way.
And how long did you leave them in the breeder net before putting them back into the larger tank with the adults? Did you put them in one by one as they reached a larger size, or decide that the whole group could be added to the tank?
About 1 month before I let them out. Daily snail feeding is required and they must reach a good size. Again, measurements on crays is difficult because they tend to grow stocky in carapace, not really length wise. I would just tell you to wait till they hit 1/4 inch but 1/4 inch can be easily obtained while they're still young. So, make sure they're visibly stocky and about the size of... this word: Stock. I do NOT include claws when measuring a crayfish. I also dumped the entire batch. I wait to make sure everyone is a good size before dumping them out. So once the runt is at a decent size, off they go.

This is really a great thread to see the process in such detail. A huge Thank You!
-Jane

And thanks for liking the thread! :-D
Any other questions are welcomed and encouraged. I start to run out on what to say in this thread...

I have had requests for a full tank shot of my CPO tank. Trust me, it's not impressive at all. I didn't scape it at all. It wasn't even meant for CPOs. Originally, it was for my tiger shrimp and boraras urophthalmoides. But then my friend surprised me with a trio and I kinda just dumped them in there and let them do their thing. Next thing you know, I fell in love and turned it into a CPO tank. I took out the tigers and left the boraras in there. There are no caves in that tank. I have a few ratty rotalas, lots of green spot algae, some blue green algae and a ratty old filter that is suppose to be strong enough for 20 gallons (or was it 30?) but it just barely trickles out water now. That tank looks awfully neglected, and it is! All I do is stop by, squish some snails and stare at my other tanks. Mainly my new SS-SSS crs tank now :)
 
You know what? I recall saying I was too afraid of trying to sex crays because I didn't want to damage the ones I had. Well, I have plenty and it's time to overcome that fear! They're hardier than many people think and I keep telling people that. It's time I start doing what I preach! Time to pick them buggers up!

And I did.
I learned how to sex them. I also developed a better way of holding them, which I will explain first.

HOW TO HANDLE YOUR CRAYFISH (Without holding their carapace!)
Scared you'll squeeze your little babies to death? Well, here's a method that I use.
First, get your fish net and scoop a crayfish out.
Now, take it out of the water and place it on the palm of your hand. Make sure your hand is wet, so dip your hand in the tank. Keeping your hands moist helps the crayfish stay wet.
Next, dwarf crays are quite clumsy and almost immobile on land. Take advantage of their weakness! They trip easy and flip over clumsily. I use my other hand and tip them over or make a hand motion to make them flip over. It sounds cruel, I know. But I don't trust my own strength and it's much safer handling them this way in order to flip em over to sex.
Once they flip over, you've got a few seconds to take a peek. They'll lie on the palm of your hand, trying to get back upright. If it takes you a while to flip em over, make sure you dip them back in the water every 20 seconds or so. Keep them wet!

Now that that tutorial is over... here are the pics!

The male out of the water! :-D Super cuteeee!!!
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This is the male. Notice the lower part of his abdomen (the lower part of the white section of his underbelly!) There's like a triangular-ish forming of small legs. That will indicate MALE.
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Now, female out of the water! Super cute too!
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This is the female. Also, look at the lower part of her abdomen, same section as the male. This time, there won't be that triangular-ish forming of small legs. What you will see is a small nub. It almost looks like a tiny penis. (Can we say penis?) This indicates FEMALE!
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To be honest, all you gotta do is remember that females have that little nub thing. If your crayfish lacks it, it's a male. If your cray has it, it's female. The images above are crays that are about 2 months old. So by this size, you should be able to sex them. You can sex them once they hit about 1/2 an inch really.

Now, check out this AMAZING (sarcasm) tank.
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This is their home folks. Impressed? Because you shouldn't be.
:lol:
There's over a dozen crays in that tank, not including the babies in the net. They're hiding in the rotala in the back left corner. Some behind the driftwood and others inside the thick fissidens bush.
Tank Stats:

- Aquasoil Amazonia I

- Some kind of HOB filter. One of them doesn't churn out water much anymore (The black one). The one in the middle was added a few days ago to create more flow to mess up the BGA in the tank.

- Ghetto heater, not sure if it even works properly. I have to set it at like, 69 degrees to hit 75 in the tank.

- Lee's breeder net for my little babies!

Plant list:

Bacopa Carolina
Cryptocoryne Wendtii 'Green Gecko'
Cryptocoryne Albida
Rotala sp. 'Green'
Rotala Indica (regular, not singapore)
Rotala Rotundifolia
Fissidens Fontanus (seen on the driftwood that lies horizontally in the middle)
Fontinalis antypiretica var. gigantea (On the driftwood to the right)

Algae - Should I even count this? LOL!

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Wow!

Excellent photography! Never expected to be so entranced looking at Crayfish "bits", LOL!

And hey... your tank is producing excellent baby CPO's! Nothing to sniff at there!

Thanks for the updates - the How-To with pictures is great!
-Jane
 
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