Rearing Fiddler Crab Larvae

[LittleRed]

I'm currently a graduate student at UNC Charlotte working on a PhD in biology, concentrating in coastal and marine ecology. My lab does a significant amount of research on fiddler crabs and right now we are focusing on a project using the Atlantic sand fiddler crab, Leptuca pugilator. UNC Charlotte is about 4 hours minimum from the coast and we therefore don't have access to a filtered seawater system.

Currently, we take carboys with us on trips to the coast and fill them with filtered seawater from the field station and we bring it back and filter it in the lab. We then keep ovigerous females in containers with the filtered seawater until they spawn, then we return them to where they were collected and rear the larvae for our research.

I know it's a long shot, but my question is, does anyone know of any instances where Ocypodidae larvae, such as ghost or fiddler crabs, have been reared in an artificial seawater mix such as Red Sea or Instant Ocean? I've been looking up papers and trying to find out if it has been done before, but most universities with marine biology programs have a filtered seawater system. We do know that the adult crabs do fine in artificial seawater, but the larvae are far more delicate and we can't really afford to risk any larvae to test it out. Does anyone have any resources or know of any instances where this has been done?

 

[Big G]

Contact Red Sea and/or Instant Ocean. They may be able to give you a source that is already using their products.

 

[Larry L]

@LittleRed Relaying a message from Geneviève Ouellet in the "Marine Breeding USA" Facebook group:

"Not fiddlers but check out Canada Aquamarine on Facebook - he rears and hermits he’s in Quebec City and the info is mostly in French but he speaks English . He might have some input!?"

 

[sabeypets]

With everything that is being aquacultured for the aquarium trade it shouldn't be a problem. IO would be the preferred salt.

 

[sabeypets]

With everything that is being aquacultured for the aquarium trade it shouldn't be a problem. IO would be the preferred salt.

 

[sabeypets]

With everything that has been raised for the aquarium trade it shouldn't be a problem. IO would be the salt of choice.

 

[LittleRed]

Contact Red Sea and/or Instant Ocean. They may be able to give you a source that is already using their products.

I have reached out to both companies, but as of yet, I have not heard back. Hopefully, they get back to me and then I can pass my findings along here for anyone interested.

 

[LittleRed]

With everything that has been raised for the aquarium trade it shouldn't be a problem. IO would be the salt of choice.

For a lot of things, that is definitely true, but in my research I have yet to find any commercial reared fiddler crabs, the vast majority for the pet trade are wild caught. Research labs rear them but ever single paper I've found uses a filtered seawater system as they're close enough to the ocean that they can do that. Fiddler crab zoea are extremely delicate and there papers by researcher, Dr. Jocelyn Crane, that suggest artificial seawater can be used in an emergency situation, but shouldn't be used long term for fiddler crab larvae. That being said, her work is fairly old and I haven't seen where anyone has tried rearing them with the much better quality commercial salt that is available now.

 

[Surfzone]

It would seem like the answer to your question is to try it out. Fiddlers are not used much in the ornamental trade out side of feeders for puffers and trigger fish. I would think that Red Sea salt in the blue bucket or IO would be fine, but I have no experience with culturing any invetabrate outside of bubble tip anemones and they do the work for you.

 

[LittleRed]

It would seem like the answer to your question is to try it out. Fiddlers are not used much in the ornamental trade out side of feeders for puffers and trigger fish. I would think that Red Sea salt in the blue bucket or IO would be fine, but I have no experience with culturing any invetabrate outside of bubble tip anemones and they do the work for you.

I would like to try it, but my PI does not want to risk losing any zoea if it doesn't work. The mortality rate of each spawning is extremely high, so risking the ones that survive that is not necessarily worth it to her.

 

[sabeypets]

On the flip side you may find that the mortality rate drops with artificial seawater. Like already stated you need to answer your own question. I would think that shrimp zoea that takes 60- 90 days to settle would be just as sensitive or more so than crab zoea. Not to mention other sensitive larvae now being raised in artificial seawater like wrasse, tangs, angels, butterfly fish, basslets, ect.
IO is going to be the best salt. You don't want to use a salt like Red Sea that has elevated alk, mag, ca, ect. I'm not knocking Red Sea it's a great salt.

 

[twinkiebabie]

I'm currently a graduate student at UNC Charlotte working on a PhD in biology, concentrating in coastal and marine ecology. My lab does a significant amount of research on fiddler crabs and right now we are focusing on a project using the Atlantic sand fiddler crab, Leptuca pugilator. UNC Charlotte is about 4 hours minimum from the coast and we therefore don't have access to a filtered seawater system.

Currently, we take carboys with us on trips to the coast and fill them with filtered seawater from the field station and we bring it back and filter it in the lab. We then keep ovigerous females in containers with the filtered seawater until they spawn, then we return them to where they were collected and rear the larvae for our research.

I know it's a long shot, but my question is, does anyone know of any instances where Ocypodidae larvae, such as ghost or fiddler crabs, have been reared in an artificial seawater mix such as Red Sea or Instant Ocean? I've been looking up papers and trying to find out if it has been done before, but most universities with marine biology programs have a filtered seawater system. We do know that the adult crabs do fine in artificial seawater, but the larvae are far more delicate and we can't really afford to risk any larvae to test it out. Does anyone have any resources or know of any instances where this has been done?

Can you advise how to read the larvae please? My female fiddler just dropped her zoea and I have one tank going with natural sea water, one with ocean water I believe is filtered from a LFS and the rest of the zoea were dropped in their moms brackish water habitat. I have a bubbler and thermometer in the sea water tanks. The brackish water habitat has no bubbler but they seem to be the most active. I bought refrigerated rotifers and am really winging it the best I can. If you can give me some guidance I would really really want to keep some alive until crab stage!!

 

[twinkiebabie]

*rear the larvae

 

[ISpeakForTheSeas]

Can you advise how to read the larvae please? My female fiddler just dropped her zoea and I have one tank going with natural sea water, one with ocean water I believe is filtered from a LFS and the rest of the zoea were dropped in their moms brackish water habitat. I have a bubbler and thermometer in the sea water tanks. The brackish water habitat has no bubbler but they seem to be the most active. I bought refrigerated rotifers and am really winging it the best I can. If you can give me some guidance I would really really want to keep some alive until crab stage!!

Sorry I found this so late - how'd it go? Any survivors?

From what I've been able to find, it sounds like you'd need Artemia nauplii (Baby Brine Shrimp) for the crab larvae to feed on, but the larval rearing differs somewhat from one species to another - do you know what species you have?

Edit: I found one source that says they used Rotifers (but I'm assuming they transitioned to Artemia at some point in the rearing process).