Breeding Journal, Species: Taliepus nuttallii (Southern kelp crab)

General
Species:  Taliepus nuttallii (Southern kelp crab)
Social Structure:  Male and Female "pair"
Size of Individuals:  3" - 4.75"
Age of Individuals:   Unknown, WC
Date added to Tank:  12/31/13

Broodstock Tank Details
Size of Tank:  30 gallon
Substrate Details:  sand
Filtration Details:  Canister filter
Water Changes:  25% every two weeks
Water Temperature:  58-60^o F
Lighting:  Fluorescent
Lighting Cycle:  12 hours on/12 hours off
Other Tank Inhabitants:  Bat stars, sea urchins, hermit crabs, assorted snails, etc.

Broodstock Feeding Details
Food Types:  Algae (Ulva and Kelp), algae sheets
Feeding Schedule:  constant grazing, every other day

Spawning Details
Date of First Spawn:  unknown
Spawn Time of Day:  unknown
Dates of Consecutive Spawns:  unknown
Courtship Details:  Male grabs onto the "back" of the female and stays with her until hatch and release
Egg Size:  unknown
Egg Color:  unknown
Egg Count:  unknown

Hatch Details
Hatch Date:  12/31/13
Hatch Time of Day:  unknown
# Days after Spawn:  unknown
Larvae Description:  Many small dots darting about the tank


Larval Tank Details
Temperature:  50-64 (ambient garage temperature)
Size of Larval Tank:  2L juice bottle
Substrate Details:  none
Other Tank Decor:  none
Filtration Details: none
Lighting:  Ambient, some fluorescent
Lighting Cycle:  about 12 on/12 off from the other tank lights
Water Changes:  100% every two days

Larval Feeding Details
Food Types:  Microalgae (live and instant), nhbbs (frozen and live)
Feeding Schedule:  constant

Metamorphosis/Settlement
Date of Settlement Start: 
Days after Hatch: 
Date of Settlement End: 
Description of Fry: 

Grow-Out Tank Details
Temperature: 
Size of Grow-Out Tank: 
Substrate Details: 
Other Tank Decor: 
Filtration Details: 
Lighting: 
Lighting Cycle: 
Water Changes: 
Size at Transfer: 
Age at Transfer: 

Grow-Out Feeding Details
Food Types: 
Feeding Schedule: 

Additional Information
(No Pictures or Videos in the Section Please)
Miscellaneous Information: 



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So, here is my "pair" in a container. You can't see the female very well because the male is just sitting right on top of her on her back.
 

 
This is the female releasing the babies with the male on her back.


 

Attached Image(s)

Here is a picture of the baby tank.

I think I might make or buy a larval catcher since I didn't get a lot of babies.

Attached Image(s)

I don't know anything about this particular crab, but looking on eol.org  about it, it looks to be a Majoidea crab and the reading I've done suggests that most of these have two zoeal stages followed by one megalopa (my research has been limited though).  I would focus on the live phyto and nhbbs.  I don't think the ulva will be all that helpful.  Perhaps it may serve as a settlement cue, but you could just add it once you see the megalopa stage.  Until then, it will just be something they can get all bungled up in.  Try to change the water 100% every couple days, but make sure to drip acclimate them after.  This is exciting!  They are very cool looking crabs!

Thanks so much! I found almost nothing about these crabs, except for their habitat and food, but just for the adults, so I am just trying to make it work... somehow. They don't seem to eat the nhbbs, so I am focusing more on the algae since they seem to clear their green water very rapidly. Last night I tinted their water a light brown, now it's almost completely clear. I removed the ulva and there were many babies on it, so that's fixed now. I'm not sure how long it will take them to molt into baby crabs since they are coldwater, but I am imagining around 2-4 weeks, hopefully on the shorter side though.

It is almost certain that they will need more than just phyto.  If you have rots, throw some of those in there as well, but you would be shocked at how small of a larvae (a crustacean larvae at least) can eat nhbbs.  So I wouldn't give up on feeding the nhbbs.  I raised some peppermint shrimp and it was several weeks in before I actually saw or could really tell that they were eating the nhbbs.  
 
Do you have a scope?  That would make it a bit easier to determine stages.  By eye, it is difficult to tell Z1 from Z2, but when they molt to megalopa, you can definitely tell by eye.  They have a way different shape and they also swim a bit differently.  I have no idea about cold water species, so I have nothing to suggest in terms of development time.  The couple crabs I've worked with have molted to Z2 around day 3 or 4, but they weren't cold water species.
 
I did find this paper though about cold water crab development, although not your species, it may give you an estimated timeline:
http://epic.awi.de/7996/1/Ang2003b.pdf
This abstract also has some good info:
http://www.ingentaconnect.com/content/umrsmas/bullmar/1986/00000039/00000002/art00025
(Let me know if you want the full paper...I may be able to get it.)
 
From what I briefly read...they will take longer (months??) :/

At 59 degrees the larvae took 3.5 weeks to change into crabs... The average temperature in my garage is 58 so hopefully they form that quickly. I have some rotifer cysts, so I will start to hatch those. I will also hatch some more baby brine shrimp. I see some copepods in their parent's tank so I might throw some of those in. According to a website I read, it takes up to a year for the eggs to hatch, so if I mess this up then I have a whole year to wait... Wish me and the crabs luck!

I, unfortunately, do not have a microscope, but you might be able to tell which instar they are from their movements. They seem to be moving their tails a bit more, but they are still in that little orb shape popping around the tank.

Both the zoeal stages are ball shaped with a tail that flicks every once in awhile.  I think I can sort of tell by eye when they go from Z1 to Z2, but it's a combination of knowing when the SHOULD and seeing a very subtle size difference or other change that I can't even really describe.  Sorry I can't help with that one without a close up pic.  I think it would be pretty fair to assume they are Z1 and will be for awhile based on what those papers suggest.
 
The megalopae will look a bit more like a squished ball...they are wider and a bit more flat looking.  They start to look a little bit more like crabs...I guess that would be the best way to describe them, although when I read over that description I realize it doesn't sound very helpful at all! lol  If you watch them closely while you are rearing them, you almost can't miss it.  One day you will peek at them and just be like, "Holy moly, megalopae!"
 
Are you sure that this particular species only spawns once a year?  The paper/abstract made it sound like SOME species only spawn once a year...hopefully this isn't one of them!  Has the male remained on the female's back after the hatch?  I wonder if he just hangs out there waiting until she has eggs ready to be fertilized and then drops off again?  That is quite odd.  Where did you get these from?  

While on vacation, along the beach of the California coast, south of San Francisco and north of LA (About half way between there), I found theses guys on top of each other holding onto a piece of dead kelp. Thinking they were dead I put them in my in the bag (because they were so cool) that I was collecting shells with and I went home. When I was in the car they started moving around. When I got home, I acclimated them to my coldwater tank, and that night they had the babies.

So this website says that the female can withhold the sperm for many months, but they mate when she molts. http://www.bbc.co.uk/natu...ern_kelp_crab_bg.shtml
Hopefully she will fertilize her eggs right away!

The male is not on top of her anymore but they are close to each other.

Also, I might be getting a microscope this weekend.

How are these doing? Still have them going?

No, sadly there was a massive die out one day, and they just never really recovered. They just went down hill from there. The last three babies were placed in a smaller container, but they just disappeared one day. I did freeze one body to see what development stage it was in. They made it to 10 days.
The parents are still alive and well. They aren't really showing any courtship signs, and they tend to stay at their own sides of the tank.

Well now there's a new species to me!  Have you checked to see if we have it classified in the database yet?  If not, do so, and consider submitting the classification request for it so you can file reports and start earning points.  Has it been done before?

No it hasn't been done before. I'm going to submit it in soon