|
For those of you who know me I've been getting more and more excited about my attempts to crack the code on breeding Mythraculus Sculptus (The Emerald Crab). As of lately I've found a lot of interesting things on the species in regards to breeding in captivity and hope to soon establish protocols and procedures for others to sucessfully breed and raise this wonderful tank inhabitant. I have thus far spent countless hours over several months time examining and changing parameters in my test system to figure out what needs to be done to induce spawning and raise the resulting larva.
Why am I doing this you ask? Early on it started as something to try as people verbally seem to mention "you could always breed these guys, I heard it's fairly easy". The crabs are quite interesting and great to watch so it made sense. Later in the process the resons changed. Have you ever tried to find definitive useful information on Emerald Crab breeding? I'm willing to bet that's how you got here as there simply isnt much out there on the species and there's even less that proves useful. I'm not a scientist, and a hack of a reefkeeper at best, but if I can find and document a process that works hopefully someone can kick off into the next level and we can acheive great success with this species. You can say it's a goal shift, but I enjoy it and hopefully my findings can help someone out there.
Why no protocols yet??
Aha.... This page is more of a placeholder and a place for my notes. To be brutally honest I have much more work to do but I want to get what I have figured out up in the hopes that someone else may be able to use the information. I could easily slap out a handbook citing my theories and assumptions as the way to go but I'd rather put info up as I confirm it. If anyone out there thinks... "But copepod geek, I simply MUST have all the information your working with" they can email me at info @ copepodgeek . com at any time! For now, just the information I am finding and confirming. Check back every few weeks. I'm hoping to have some great breakthroughs in the coming months! On to the info
Breeding Mythrax Crabs
Notes and findings from the Copepodgeek
Gender Density and Sexing of the Emerald Crab:
Gender density for breeding is one area that could esily have more study in my realm, however I am finding that a 3:1 ratio in favor of females has allowed me the opportunity to induce spawning more often and with great success. There is good documentation out there regarding sexing the emerald crab and probably the best can be found at http://www.projectdibs.com/forums/showthread.php?t=1278 Project DIBS is a great resource for a ton of info if you havent already stopped by. The easiest way to think of how this sexing peice works is that the females carpace is for the most part one solid section under the abdomen, it opens from the front like a flap (remember those pajama flaps, just like that) during molting or more importantly during release of larvae. The series of plates extend across the entire bottom of the crab with no separations in the middle.
Initial broodstock tank parameters:
I feel it's important for all to know my initial broodstock tank parameters. While not much of a deviation from the norm for marine reefs save a couple of oddities here and there this will come to light for induction of spawning. Standard parameters are held at 78* F for temp, Specific Gravity of 1.026. The tank is high nutrient however nitrogen levels are kept low and most times are undetectable. The broodstock tank is not equipped with a skimmer however macro algaes are used for nutrient export. Lighting is via NO flourescents and run on a 14 on 10 off cycle. A few small peices of live rock are provided for habitat. Water changes are only performed in nutrient increase events or when inducing spawn (see inducing spawn)
Feeding of Broodstock:
Broodstock is fed heavily to encourage spawning. A mixture of Marine flake and Formula One pellets are fed two to three times a day in an amount large enough to allow for leftover food to settle within a few minutes for later feeding of the broodstock that remains hidden in the live rock.
Inducing Spawning:
Thats what you were after wasnt it. Thus far I have been able to recreate success with the following procedure a total of 6 times. While I cannot guarantee success I am currently delving into the statistics and parameters to find out exactly what is inducing the spawns. I post this now as I have a good bead and am hoping for input from fellow hobbyists.
Spawning seems to be successful most often when induced on a 4 week cycle, more examination of this needs to be done (as I have not been able to record which female has spawned each time). The spawning cycle begins with a slow rise in salinity from 1.026 to 1.029 over a two week period of time. The broodstock system is then maintained at increased salinity for a period of 7 days and then water changes are performed over a period of 24 hours to bring the salinity back down to 1.026. This sharp drop in salinity seems to be the trigger for spawning. Iodine is then added in standard reef dose amount to the water to aid in the future molt.
Within a week the shells of the females will begin to lighten as they prepare for a molt. Females who are carrying can be spotted and identified easily as the underside of the carpace will open up like a flap revealing larvae waiting to be ejected. Larvae are typically expelled and the female begins full molt within 6-10 days from salinity bounce.
Thats it for now!!!
I can ramble on about other crap I'm trying, a ton of other theories, and what I'm doing today (today is spawn day, the flaps open and the fry are ready.... get to collect and plop the larvae in the kreisel). But it wont do anyone else much good. I'd love to hear from others that have attempted to spawn Mythrax and compare notes for sure! Drop me a line if you have tried or decide to try and lemme know what you know.
Yours in plankton land,
~J
|
