Well I think I must have things just right for my crabbies, because two of my females have eggs. One is absolutely loaded. Both sets are still dark, not light as in close to hatch time.
What I'm wondering is whether or not anyone has any experience actually trying to hatch and raise zoeae. I understand that they can either be fed newly hatched rotifers or sometimes finely ground fish food. I also understand that the female is supposed to take her eggs to an intertidal pool and disperse them there in time for hatch.
What I need to know is how to set up a place where she can do this and feel natural (I have some ideas), basic ideas on how to set it up (I assume salt-tank salinity, aeration, no filtration, teensy starter shells on up, and a crawl area).
Also, other than being maddeningly tedious and very difficult, if I'm the type that enjoys that type of thing has anyone done it?
At the very least, I'd like to be able to release the hermies into an intertidal pool in Galveston so that they have a chance there.
Looking forward to replies,
Nathalie
Two females loaded with eggs
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Guest
Topic author
just a shot in the dark
ok... I tried to get to a site where a very interesting article was found on c.compressus... but for whatever reason I have to now "subscribe" to see it (at least I managed to print it first!)... so without further ado (I apologize in advance for typos.. this is retyped, since it actually came from a pdf file):
from the Journal of Crustacean Biology, issue 21, pages 715-732
Renae Brodie and Alan W. Harvey
(under Materials and Methods)
Several ovigerous C. compressus (generally 3-10 crabs) were intercepted just above the surf zone in Culebra Beach, Naos Island, Panama, shortly before hugh tide on evenings from March through May 1997. Each crab was kept inside a round plastic washtub (diameter = 0.5m) partly filled with damp sand into which was placed a 300ml Pyrex dish filled with filtered sea water. Tubs were checked every 2-3 hours until at least one female had shed zoeae into it's water dish.
Larvae from nine females were reared for this study. One batch of larvae each hatched on the evenings of March 7, May 4, and May 6, respectively. (three batches total). These zoeae were housed individually in partitioned plastic boxes holding 20ml of filtered sea water in each of 18 compartments. Three females shed larvae on the evening on April 2 and three more on the evening of April 3; on each occasion the three batches were combined and larvae were randomly selected for rearing. These larvae were placed five to a compartment in larger plastic boxes holding 75ml of filtered sea water in each of 24 compartments and were not tracked individually through development. All subsequent rearing took place at the Smithsonian Tropical Research Institute's marine facilities on Naos Island, Panama.
The larvae were reared on a 12:12 L:D light cycle at 26C, the average local sea-surface temperature for several days before the first batch was collected. Zoeae were transferred to clean compartments and fed Artemia nauplii daily; newly hatched Artemia were consumed for the first two weeks of development, after which they fed upon larger 1-2 day old Artemia.
When the March 7 batch of individually reared larvae metamorphosed into megalopae they were moved to small plastic conatiners holding about 4ml of sea water. Each container was sunk into damp sand in the larger compartmentalized boxes, so that indiviodual megalopae had the first opportunity to leave sea water. Megalopae were fed fish flake food daily and provided small vacant gastropod shells (Nerita modesta). On April 24 the 16 surviving megalope were moved to covered plastic cups (diameter = 9cm) also containing sea water and sand and placed outside in an open-air covered arena where they experienced natural daily fluctuations in light and air temperature....
So uhmm... looks like there have been some successes with hatching eggs. It's a pity that this is now subscriber only, because the entire article (18 pages) is pretty interesting.
from the Journal of Crustacean Biology, issue 21, pages 715-732
Renae Brodie and Alan W. Harvey
(under Materials and Methods)
Several ovigerous C. compressus (generally 3-10 crabs) were intercepted just above the surf zone in Culebra Beach, Naos Island, Panama, shortly before hugh tide on evenings from March through May 1997. Each crab was kept inside a round plastic washtub (diameter = 0.5m) partly filled with damp sand into which was placed a 300ml Pyrex dish filled with filtered sea water. Tubs were checked every 2-3 hours until at least one female had shed zoeae into it's water dish.
Larvae from nine females were reared for this study. One batch of larvae each hatched on the evenings of March 7, May 4, and May 6, respectively. (three batches total). These zoeae were housed individually in partitioned plastic boxes holding 20ml of filtered sea water in each of 18 compartments. Three females shed larvae on the evening on April 2 and three more on the evening of April 3; on each occasion the three batches were combined and larvae were randomly selected for rearing. These larvae were placed five to a compartment in larger plastic boxes holding 75ml of filtered sea water in each of 24 compartments and were not tracked individually through development. All subsequent rearing took place at the Smithsonian Tropical Research Institute's marine facilities on Naos Island, Panama.
The larvae were reared on a 12:12 L:D light cycle at 26C, the average local sea-surface temperature for several days before the first batch was collected. Zoeae were transferred to clean compartments and fed Artemia nauplii daily; newly hatched Artemia were consumed for the first two weeks of development, after which they fed upon larger 1-2 day old Artemia.
When the March 7 batch of individually reared larvae metamorphosed into megalopae they were moved to small plastic conatiners holding about 4ml of sea water. Each container was sunk into damp sand in the larger compartmentalized boxes, so that indiviodual megalopae had the first opportunity to leave sea water. Megalopae were fed fish flake food daily and provided small vacant gastropod shells (Nerita modesta). On April 24 the 16 surviving megalope were moved to covered plastic cups (diameter = 9cm) also containing sea water and sand and placed outside in an open-air covered arena where they experienced natural daily fluctuations in light and air temperature....
So uhmm... looks like there have been some successes with hatching eggs. It's a pity that this is now subscriber only, because the entire article (18 pages) is pretty interesting.
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Guest
Topic author
That's brilliant, thanks! Just the type of information I was looking for. My females had a shell party this weekend, so I don't know which is which. I'm going to remove all the suspects to another cage with seawater and see if anything happens.
I'll post if I have any luck, or even if I don't. Who knows!
Thanks again, and have a great weekend!
Nathalie
I'll post if I have any luck, or even if I don't. Who knows!
Thanks again, and have a great weekend!
Nathalie
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Guest
Topic author
just curious as to how the females are doing? 
I hope all is well and please keep us posted. did the females get impregnated while in your care 
or did you purchase them and then discover that they were carrying eggs? :roll: i've read that this is breeding season and that some kiosks and petstores might have some female with eggs and they dont even know it. anyway good luck ! 
I hope all is well and please keep us posted. did the females get impregnated while in your care or did you purchase them and then discover that they were carrying eggs? :roll: i've read that this is breeding season and that some kiosks and petstores might have some female with eggs and they dont even know it. anyway good luck ! -
Guest
Topic author
My girlies are doing well, though after their shell change it's hard for me to tell who is who. I think I'm going to mix shells up again and see if they'll switch for me.
One of the crabs (the one with the fewer eggs) was just recently purchased, but from Petsmart - I don't know that there will be much luck with that. The one that is loaded has been in my tank for a long while.
I had to laugh at the crabbies are addicting part. I actually had dreams last night of going to the beach and finding dozens of crabs, all different sizes. Ahhhhh what a dream!
Nathalie
One of the crabs (the one with the fewer eggs) was just recently purchased, but from Petsmart - I don't know that there will be much luck with that. The one that is loaded has been in my tank for a long while.
I had to laugh at the crabbies are addicting part. I actually had dreams last night of going to the beach and finding dozens of crabs, all different sizes. Ahhhhh what a dream!
Nathalie