Harlequin shrimp questions

[lnevo]

Hey all,

 

I proposed these questions in MR but I thought that you guys would probably have some very different and valuable feedback to these, so here goes...

 

Sunday I purchased a Harlequin shrimp to take care of my asterina "problem". I have a few questions regarding long term care and looking for opinions.

 

First off the asterinas have been up on the glass en masse. Should I be collecting them and transfer to the sump to keep a population going?

 

If your feeding them asterinas, can that be a long term diet? How many asterinas would you need to feed them on a regular basis?

 

Asterinas aside, I'm thinking of getting some chocolate chip stars and keeping them in the fuge area of my sump. I heard you can rotate breaking arms off of them. How many can you keep in a small fuge section like that? Would i need to feed them separately or can they scavange what makes it down there? And if you feed them whats the best way to do so?

 

My other option is to get sand sifters but theres no sand in the fuge so it would have to be like a once a month purchase and just toss in the tank.

 

What do you guys do to care for harlequins long term?

 

Oh and do you keep them solo or in pairs, I'm thinking of getting a female to join the male I purchased.

 

Thanks in advance

[howaboutme]

Don't they eat linkias only? Didn't realize they eat asterinas too.

Edited April 25, 2014 by howaboutme

[lnevo]

Linkias fromias chocolate chip, sand sifters. I think the only ones they dont eat are brittle stars which are too fast

[YHSublime]

Everything you said is what I know. I think you could keep two starfish and rotate "legs." I don't feed anything in my sump. So far I have a gorilla crab, 2 emeralds, a long spine urchin, and a coral banded. It's not a place you want to go sticking your hands about, lol. I bet you would be fine letting it keep your asterinas in check, no worries, but jmo.

[OUsnakebyte]

Well, unfortunately, many of these questions should have been researched and asked prior to buying the shrimp.  And, in general, this is one of those fantastic-looking reef animals that should probably be left on the reef.

 

- They have been known to prey on Crown of Thorns Sea stars (COTS).  In an era of declining predation on COTS (removal of predators such as the Triton's Trumpet snail and larger predatory fish, such as Napoleon wrasse), this is yet removal of another predator of COTS.  Is removing H. picta going to have an increasing impact on COTS populations?  I don't know, and I'm not sure there have been many studies yet.  But, we do know that removing predators from an ecosystem can see a population explosion of the prey item - and we've already seen that for COTS with removal of the above-mentioned predators (in addition to them possibly getting a jump-start on life for other ecological disturbances).

 

- The practice of harvesting reef animals to feed another reef animal is also not very sustainable.  After they finish off your asternina problem, you'll need A LOT more than two CC stars (or any large star for that matter).  Many stars do have an incredible capacity for regeneration of a limb, but that regeneration is not going to happen nearly fast enough to feed your shrimp, let alone a second one if you purchase it.  No way rotating out two stars is going to be enough - possibly 20 stars, and even then... probably not.  But again, the point is that you have to keep flying in reef animals to feed a reef animal.  How much fossil fuel is that shrimp going to "consume" over its life in your tank?

 

If my tone sounds scolding, it's not meant to be - so please do not try and take it as such.  But again, a little more research on the front end could have answered many of these questions.  But, in general I do not favor importing these animals b/c they are a predator of a predator of already stressed ecosystems, and there does not seem to be a good way to feed them without having to continually import reef animals to feed them.

 

Cheers

Mike

Edited April 26, 2014 by OUsnakebyte

[lnevo]

I knew what i was getting into. It was not un-researched. I'm looking for tricks and tips and peoples experience in keeping stars for feeding. If i have to keep buying stars i knew what i was getting into. And recent news on the CoT invasion has been pretty positive coming out of Australia.

[OUsnakebyte]

I knew what i was getting into. It was not un-researched. I'm looking for tricks and tips and peoples experience in keeping stars for feeding. If i have to keep buying stars i knew what i was getting into. And recent news on the CoT invasion has been pretty positive coming out of Australia.

 

I certainly believed you researched the shrimp to know that they only eat certain stars and would possibly help your asterina problem; however, I would file the questions asked above under "research prior to buying" to know if rotating CC stars is a viable strategy.  And, I believe that it isn't.  It takes a spindly-armed brittle star months to regenerate its small arm.  I have a cold-water Pisaster star at work that was preyed upon by a tank mate in which two of its arms were eaten.  It is now 3 years later, and this star has barely put on 3cm of regenerated arm growth.  Now, this is a cold-water species, but it is similar in size to a CC star - more so that a brittle.

 

The point is, those stars are likely not going to regenerate arms fast enough to be a viable feeding strategy - which even begs another question... Are our tanks even an environment fit to encourage CC star arm regeneration?  If you have 10-20 in a sump, some wounded, some not... would they cannibalize each other, if one sensed the other was injured?  How many stars would you even need to feed a shrimp like this for the rest of its life?  Again, all questions I would encourage asking before buying.  Heck, you could have even purchased a CC star, hacked off an arm and threw it in your sump to see how long it would take a star to regenerate an arm.  Then, you could begin with some data before purchasing.

 

Regardless, once again, I believe it is not a good idea to keep bringing animals in from the reef to feed these animals.  In an era of searching for less impact and moving toward sustainability, it is my opinion that H. picta does not fit that model.  Don't get me wrong - I think they are fascinating and amazing and completely awesome looking.  But, one animal that should - IMO - be left on the reef, given its specialized feeding requirements AND that it is a direct predator on COTS, which brings me to......

 

News from Australia and COTS?  The last paper I saw from 2012 suggested that the GBR has declined at least 50% during the past 27 years, and one of the three major factors was COTS outbreaks.  If you are talking about the recent program of injecting the stars and subsequent removal, then sure, that's all fine and dandy, but once again... why is the Australian government having to pour money into this venture to begin with?  Well, juvenile COTS have likely been given an advantage in the form of more phytoplankton during their larval phase, and the adults have seen decreases in predation.  But, this is Australia we are talking about - they have much more money to pour into this research and implement a program to send diver teams out to the reef like this than say does... Indonesia, Philippines, Micronesia, Palau, other island nations, etc., etc., etc.....  COTS are not restricted to the GBR.

 

Look... I would try to prevent someone from buying a Triton Trumpet shell for their coffee table or Napoleon wrasse on the menu just the same as I will try to discourage hobbyists from buying H. picta for their tank - all are natural predators of COTS.  And, again, given their specialized feeding requirements, these are probably animals we should move away from collecting/importing altogether.

 

Cheers

Mike

[YHSublime]

I know I have often thought about adding a pair to my reef. That's good advice for future members looking to make a purchase, and maybe our vendors will get to read it as well. Either way, looks like he has one now, so wondering if there is anything we can do to help...

 

This popped up on my FB feed the other day, thought you might find it useful, although not a lot of people have answered. I have known several reefers that have kept them alive for years (which I know isn't great in the grand scheme of all things living) but maybe helpful. The last person I can remember having a pair in this area was Jan (Jans food.) I think they survived solely asterina's. Somebody local bought them off her, I wonder who that was...

[lnevo]

Sorry, I was not about to buy starfish and start hacking pieces off of them when doing so would just be destructive. I understand your concerns and I took it into my account during my decision to solve my asterina problem. I appreciate your feedback and while it's valuable information, it doesn't help answer my questions or those who would come after me searching for similar. I'm looking for first hand experience and what can be done to maintain these creatures in captivity. Going over the politics and biological issues to avoid this scenario do not answer the question or help anyone else in the same shoes. I understand if due to the above, keeping Harlequin's are not a popular option at WAMAS and I can respect that.

 

Isaac, I did see that link and plenty of other similar ones (lots of dead ends..), so thanks for that. I'll see if I can find some of the better ones that I uncovered as well as documenting what I am able to discover based on my own experiences down the line.

[dave w]

I bought one as a gift for a friend's tank about 25 years ago.  I admit that it was an impulse buy (I was young) and I did little research beforehand, although back then there was much less information available and no internet groups to disseminate information.  Anyway, the harlequin ate every slug and snail in the tank before trying out bristle worms and about every other thing it could reach before dying of starvation a couple months later.  

 

There were some good articles on propagating harlequins in captivity, I remember one by Joyce Wilkerson about 20 years ago in particular.  I recall that they rotated linkias in and out of the broodstock tank and that they did NOT cut off starfish arms.  The harlequins pulled tissue out of the starfish and certainly ate at it, but I recall that the linkias recovered relatively quickly.   

 

It has been a long time since I read these articles and my memory may be faulty.  One would need a large tank to keep a large and healthy supply of starfish, and the ethical issues that Mike raises are important.  Even if your tank were large enough to have a sustainable supply of starfish as food and you had a cheap starfish to work with, harlequins are a difficult species from an ethical standpoint.  I would love to propagate them because with a good setup they are supposed to be easy to propagate, but there would be the larger ethical question by Mike: even if I successfully raised a hundred baby harlequins, they would be sold to tanks that needed more live starfish as food.