Blue leg hermit crab expecting babies?

clownfishmama

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When it was stretching I saw some orangeish reddish balls along its back are these eggs?
 

Paul B

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Yes, they spawn all the time. It's hard to see because of their shell. Sometimes, usually at night you can see hundreds of tiny swimming crabs. But you need real good eyes.

These guys lived to about 12 years old and would spawn all the time. But very hard to see unless they change shells.

 
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Yes, they spawn all the time. It's hard to see because of their shell. Sometimes, usually at night you can see hundreds of tiny swimming crabs. But you need real good eyes.

These guys lived to about 12 years old and would spawn all the time. But very hard to see unless they change shells.

Should I put it in a breeder box? I’ll try and rear them. And when do I expect for the babies to be born
 

Cheese Griller

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Should I put it in a breeder box? I’ll try and rear them. And when do I expect for the babies to be born
AFAIK nobody has successfully raised the larvae of blue legged hermits before, and if they were to, a breeder box wouldn't cut it. They would require a dedicated setup just to larval rearing, which is difficult to make especially since this has never been accomplished so far. I know people have successfully raised terrestrial hermit crabs before, so that may be a place to start looking at rearing setups.
 

ISpeakForTheSeas

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Should I put it in a breeder box? I’ll try and rear them. And when do I expect for the babies to be born
You'll want a larval rearing tank (sounds fancier and more complicated than it is), and you'll need both brine shrimp nauplii (Baby Brine Shrimp) and shells for them to settle into - the shells are likely the hardest part.

For a very simple larval rearing tank, take a container, put saltwater in it, add an airstone/gentle sponge filter, and - if needed - a heater that is blocked off by a fine mesh (preferably less than 40 microns).

Some larvae may need more than just room-lighting/ambient lighting too, but, IIRC, I don't believe these do.

Anyway, once you have the tank set up, you basically just add the larvae (probably easier in this case to add the hermit with the eggs and just pull it out once the eggs have hatched), add the baby brine shrimp, add some phytoplankton (like Tetraselmis or Isochrysis) to tint the water green (this is done for a number of reasons I can explain if you want), and watch - as they grow, you may need to increase the size of the food you're offering them, and once they get to settlement you'll want to start offering regular fish food.

To summarize:
-Little, simple tank.

-Add hermit larvae.

-Add baby brine shrimp (food) and phytoplankton.

-Adjust feeding as needed as the larvae grow; start feeding regular fish food in addition to the brine shrimp around settlement.

-Add tiny shells for larvae to settle into.

-Adjust shell size as needed as settled juveniles grow.

For an example of a simple larval rearing setup:
For specific info on hermit rearing:
Once you've got the crabs spawning, I'd assume the shells would be the hardest part (as mentioned above). Hermit crabs of a variety of different genera and species have actually been reared with some frequency in laboratory settings, but to my knowledge they rarely get the crabs to actually settle past the megalopa or glaucothoe stages (likely due to the lack of shells). Rearing them to that point, however, typically only takes Artemia nauplii (Baby Brine Shrimp)
For the shells, you could either try to breed your own snails for the shells, or you could make your own (3D-print or hand make). The first requires the right kind of snails while the second requires you to shape the inside of the shell in a way that is preferred by the hermits (the inside is the most important part - they don't seem to care much about the outside - and you'd need to imitate their preferred snail shell interior to the best of your abilities). Both methods would require you figuring out the proper size of shell for the hermits - if there's a specific species you'd like to breed, you could estimate size based on the average larval hermit size for that species at the time they go to molt to leave the megalopa/glaucothoe stage and enter the first crab stage.
some megalopa stage hermit crabs have a carapace length of 0.8 to 1.0 mm (and some may be even smaller than that). So, you may need shells in the 1.0-2.0 mm range as well.
Hermits will accept glass shells - again, as long as the inside is right, they'll usually take it (though there have been studies showing that the hermits will be more likely to accept a shell if you coat it in calcium carbonate).
For the specifics of the feeding and rearing tank stocking, it seems most labs stock ~100 hermit larvae per liter, and the only report I found that listed the amount of BBS fed used ~5,000 nauplii per liter (so roughly 50 nauplii per hermit).
I'll see if I can't dig up some info on a timeframe for your eggs and on preferred shells for these, but that's all I've got for now.

You may see better survival with copepods, but start with the Artemia (brine shrimp) since that has a proven track record with hermits at this point.


___________________________________________________________________________________
Edit: Found the shells - these guys prefer Cerithium spp. shells - so Cerith shells are their preferred shells. Assuming you can't get a ton of the shells in small enough sizes, you can imitate/DIY these in a few different ways - silicone molds (take a mold of the interior; cover the mold with a sturdy material and remove the interior mold before the material finishes curing/drying); 3D printing, DIY rock, sculpted from clay, etc.; figuring out which material is best to provide sturdy yet lightweight shells may take some experimentation.

Also, keep in mind that it's best if you imitate the shells as they would actually be at the size you need (an adult snail shell will have more spirals and such then a young snail; the hermits will likely prefer the shell of the snail as they would find it in the wild).

If you don't have any access to tiny shells of the species, then let me know or look up what the shell would be like at those sizes and imitate it as best as you can.

As a note, the shells of the adult hermits (particularly the females) also plays a major role in their reproduction, seriously impacting the number of eggs they carry in a clutch.

I can't find a timeframe on the hatching for these guys, but they reportedly hatch after lights out (which is fairly common).
 
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Paul B

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Should I put it in a breeder box? I’ll try and rear them. And when do I expect for the babies to be born
About impossible in a home tank. But good luck
 
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clownfishmama

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You'll want a larval rearing tank (sounds fancier and more complicated than it is), and you'll need both brine shrimp nauplii (Baby Brine Shrimp) and shells for them to settle into - the shells are likely the hardest part.

For a very simple larval rearing tank, take a container, put saltwater in it, add an airstone/gentle sponge filter, and - if needed - a heater that is blocked off by a fine mesh (preferably less than 40 microns).

Some larvae may need more than just room-lighting/ambient lighting too, but, IIRC, I don't believe these do.

Anyway, once you have the tank set up, you basically just add the larvae (probably easier in this case to add the hermit with the eggs and just pull it out once the eggs have hatched), add the baby brine shrimp, add some phytoplankton (like Tetraselmis or Isochrysis) to tint the water green (this is done for a number of reasons I can explain if you want), and watch - as they grow, you may need to increase the size of the food you're offering them, and once they get to settlement you'll want to start offering regular fish food.

To summarize:
-Little, simple tank.

-Add hermit larvae.

-Add baby brine shrimp (food) and phytoplankton.

-Adjust feeding as needed as the larvae grow; start feeding regular fish food in addition to the brine shrimp around settlement.

-Add tiny shells for larvae to settle into.

-Adjust shell size as needed as settled juveniles grow.

For an example of a simple larval rearing setup:
For specific info on hermit rearing:





I'll see if I can't dig up some info on a timeframe for your eggs and on preferred shells for these, but that's all I've got for now.

You may see better survival with copepods, but start with the Artemia (brine shrimp) since that has a proven track record with hermits at this point.


___________________________________________________________________________________
Edit: Found the shells - these guys prefer Cerithium spp. shells - so Cerith shells are their preferred shells. Assuming you can't get a ton of the shells in small enough sizes, you can imitate/DIY these in a few different ways - silicone molds (take a mold of the interior; cover the mold with a sturdy material and remove the interior mold before the material finishes curing/drying); 3D printing, DIY rock, sculpted from clay, etc.; figuring out which material is best to provide sturdy yet lightweight shells may take some experimentation.

Also, keep in mind that it's best if you imitate the shells as they would actually be at the size you need (an adult snail shell will have more spirals and such then a young snail; the hermits will likely prefer the shell of the snail as they would find it in the wild).

If you don't have any access to tiny shells of the species, then let me know or look up what the shell would be like at those sizes and imitate it as best as you can.

As a note, the shells of the adult hermits (particularly the females) also plays a major role in their reproduction, seriously impacting the number of eggs they carry in a clutch.

I can't find a timeframe on the hatching for these guys, but they reportedly hatch after lights out (which is fairly common).
Oh wow, thank you very much! My father suggested I leave it and let the fish eat the eggs. But I plan to do this sounds like a challenge but I'm willing!
 

ISpeakForTheSeas

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Can you maybe link me some sites to find all the stuff I need if not it's fine!
For the brine shrimp and phyto - culturing your own is ideal (it gives you a stable, constant supply that doesn't break the bank), but that may feel too overwhelming at the moment in addition to trying to rear hermit larvae, and you can make do with buying as needed (the phyto is much harder to come by in a pinch than the brine shrimp for these purposes).

If you don't want to try culturing them, then you can buy a thing of brine shrimp eggs and just add enough per day to the tank to feed each hermit larva when the brine shrimp eggs hatch (honestly, you probably wouldn't even need 2 oz for a single batch of hermit larvae if you have a decent hatch rate).

[Ideally, you'd hatch the eggs out of the tank, remove the shells, and add just the nauplii, which you can do in a number of ways (with a hatchery, a net/sieve, or by decapsulating the eggs before adding them), but that is an extra step which I would honestly ignore if it makes the attempt feel more daunting at the moment. You can always worry about this with future attempts.]

I would however, recommend culturing your own phyto regardless of if you want to culture the brine shrimp. Isochrysis would be ideal, but it's notoriously difficult to culture. So, instead, you may want to go with something like Tetraselmis, which should be much easier to culture. If you have somewhere that stays warm and gets plenty of sunlight, you wouldn't need a light for the phyto culture; if you don't have somewhere like that for it, then you would need a light (you can absolutely get a cheap light for this, you definitely do not need a fancy reef light).

For the eggs:
This place also sells stuff like hatcheries, nets/sieves, etc.

For the phyto:

(Amazon links often don't work on here anymore, so if this link doesn't work, it's Mercer of Montana 16 oz Tetraselmis [~500 ml]).

For the food once they're ready to start settling, I'd recommend TDO Chromaboost (probably the X-Small, but possibly Small, depending on the size of the hermits).

For the shells - again, this is the hard part. I don't know how big the hermit you're working with (Clibanarius tricolor) is at it's megalopa stage (the stage it goes to settle at), but looking at other species in the genus, I'd expect them to be around 1-3 mm at the time of settlement. The only place I can find that sells Cerithium (or similar) shells that might work for that size is Cinquantagefleur's ebay shop:
They also have these shells available in a wide variety of sizes, so you should be able to get ones that are appropriately sized for the hermit to transition into in their shop as well - I expect you'd need ~1/8"-1/4" (~3-6 mm) shells to start, then ~1/4"-1/2" (~6-12mm), then 1/2"-1" to finish out their growth. I doubt you'd need larger than 1" shells, but you can find larger if needed.
 

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