can you breed emerald crabs?

[travis_]

I went and bought what I am told is a female and male emerald crabs for my refugium. I checked out their adomen and they are both pointed which I typically take as male, but the LFS store lady assured me they were female and male, one has very large claws, the other very small. They appear to be very happy in my refugium eating hair algea, I am amazaed at how much of a reduction I have already seen in just over 1 week.

First question, even though they both have pointed abdomen, could these still be male and female? I didn't get a great look so I am not 100% sure.

Second question, could I get them to breed? There are no preditors in this refugium so I was hoping nothing would eat the babies.

thanks,

 

[Herefishyfishy]

I went and bought what I am told is a female and male emerald crabs for my refugium. I checked out their adomen and they are both pointed which I typically take as male, but the LFS store lady assured me they were female and male, one has very large claws, the other very small. They appear to be very happy in my refugium eating hair algea, I am amazaed at how much of a reduction I have already seen in just over 1 week.

First question, even though they both have pointed abdomen, could these still be male and female? I didn't get a great look so I am not 100% sure.

Second question, could I get them to breed? There are no preditors in this refugium so I was hoping nothing would eat the babies.

thanks,

On sexing Mithrax sculptus, Some say that females are more likely to eat algae, and less likely to cause trouble. I cannot say this is true or not, but to play it safe we picked female Emeralds. There are two pieces that make up the crab, the carapace and abdomen. Generally the sex of Emeralds can be identified by their abdomen. The abdomen is only used in mating, and is what you want to look at on the underside.

On Males, there will be a disruption of the horizontal plates that looks very much like the Eiffel Tower. It starts at the rear legs and merges up the abdomen towards the mouth

They do lay eggs and hold them untill hatched. The problem is keeping the larvae well fed on plankton and not predated on by other inhabitants

 

[Chichas01]

emrald crabs

My only comment would be that if your refugium is for the purpose of providing a refuge to pods and worms and other critters that provide food/benefits for your fish and the overall system, then those will probably be wiped out by your emerald crabs. They eat algae, but they really eat anything that tastes good them. I would put them in your sump with a little LR.

 

[travis_]

I have been spending a lot of time watching my crabs, and so far they have no interest in the other critters, worms, etc. I saw a small bristle worm crawl right past a crab while he sat happily eating hair algea. If I do see any decline in life I will take them out. Plus I see the crabs as being to slow to catch any of the pods and worms anyway.

Also, I feed my tank daily with DT, I feel that is why I have such a health pod and worm popualtion. I would hope that this dauily feeding could sustain the crab babies, but who knows and I can only hope. I am also not agains setting up a seperate tank for rearing the babies, I am planning on doing this anyway to raise rotifers.

thanks for your input!

 

[acrylic_300]

Mine had babies...it was pretty cool. I just happened to be checking the tank out after dark. I noticed a spooky amount of "pods" swimming everywhere. Further inspection revealed an emerald crab up high on the rock-work fanning babies out of a flap on her underside into a high flow area.

Even in a 300 gallon tank it looked like a snow storm. None of them lived, but if all of them had lived I would be in trouble. I'm guessing it was around 5,000 pods.

It was akin to witnessing one of the Wonders of the World.

 

[Bricky]

I too caugt my crab spawning and got lucky with some pictures. Maybe one or two will live and I won't have to pick up anymore for the near future.

 

[Bricky]

I saw the female pictured above again last night (1/2/09) with another round of eggs. She was also only inches away from a male. I wish I had taken more pictures.

 

[travis_]

I saw the female pictured above again last night (1/2/09) with another round of eggs. She was also only inches away from a male. I wish I had taken more pictures.

that is really cool, hopefully some will live. Do you have a refugium? If so, what about scooping out some of the babies and putting in there away from preditors?

 

[azgard1]

anyone know the approx life span of a crab?

 

[travis_]

one of my female emerald crab's abdomen looks extended, like there are a bunch of eggs or something under it. Does this mean she is going to lay eggs? Should I remove her to a tank without preditors? Maybe the one that the my mysis shrimp are living?

thanks for the help,

Travis