Urchin spawning stress related?

[Maxx]

I have long spined urchin, Diadema setosum, which has spawned on three occasions that I know of. It climbed up to the highest point in the tank and began broadcast spawing, and subsequently caused my skimmer to go completely nuts. It has done this in evening, just before the tank lights went out for the night. The last time it did this was immediately after a good sized water change, (30%).

I've had the urchin for a little over a year, and its body is about the size of a tennis ball in width.

Do these urchins spawn in response to stress, (ie water change), or just when "happy"?

I know tridacnid clams will spawn when stressed, and BTA's will split when stressed, so I'm not sure if these urchins do too.

Nick

 

[NaH2O]

Nick - I've read both....people see their urchins' spawn with or without water changes. Were you doing any kind of tank maintenance prior to the spawn (water change, coralline scraping, carbon change, etc.). I wonder if your urchin was just feeling a little romantic . Did you have any kind of flux in temperature, pH, and/or salinity? DonW's urchin would spawn every time he scraped the coralline algae from the tank: Urchin Spawn.

 

[Maxx]

No scraping done this last time...just a water change...
I'd prefer if it was gonna make a mess, it would do it before I did a water change as opposed to afterwards...

Kinda defeats the purpose, ya know...

Oddly enough...I didnt remember my post on Don's thread.

Nick

 

[iwantone]

Urchins will spawn with stress. In science classes they do it with a low voltage current...

 

[Maxx]

Interesting...didnt know that. It wasnt spawning when my Koralia 2 was shorting out in the tank. My Ritteri anemone wasnt happy, and thats what clued me into the problem....so I immediately removed the Koralia, (since replaced by manufacturer as part of a recall), and never saw anything more from that...

It was spawning before that though...

If its spawning is stress related, I have absolutely no idea what could be causing the stress. I have SPS, Clams, and the Ritteri anemone, in addition to a pair of percula clowns, a Tomini Tang and Royal Gramma. There is nothing in the tank that would attack or harass the urchin to the point of stressing it, and there are no chemical issues/husbandry issues that I'm aware of that would stress it out and not the anemone, clams or corals...
So I'm at a loss...

Nick

 

[Anthony Calfo]

it would not take much at all to stress induce a spawn. Just a spike in salinity from a tardy evap top off (or water change with temp difference).

Even a slight injury (bumping or tearing the urchin away from anchored tube feet) can do it.

Tearing a bristleworm in half, for example, often incites the other worms to spawn on the chemical cue.

 

[Maxx]

Interesting...

Didnt know that. Thanks Anthony.

Nick

 

[auqua man]

http://www.reeffrontiers.com/forums/showthread.php?t=27388
mine would spawn every time I did a water change bummer.
this thred is about the same urchin you have.

 

[Maxx]

Mine has ocassionally munched on a coral...but nothing obscene that didnt grow back pretty quickly. Like Don W mentioned in your thread, once I gave it a "haircut", the muching stopped and it was able to get back into areas it couldnt before.
Incidently, I've trimmed the urchins spines before, and not had any spawing episodes....so obviously that isnt a stress...
Nick

 

[Paul B]

I used to have an Urchin Collecting Business (Urchin Searchin Enterprise)
and I once had 24 New York purple urchins spawn in my reef all at once. I think it happened a couple of days after collection so I can assume it was either stress or temperature related. You can't imagine the mess. My skimmer has a 5 gallon collection bucket which filled up and overflowed another few gallons.
Paul

 

[Planet Reef]

Tearing a bristleworm in half, for example, often incites the other worms to spawn on the chemical cue.

Anthony,

Do they need to be close to epitoke stage or can this be done at any time?

 

[Anthony Calfo]

nope not at all... nor do epitokes occur in aquaria much at all.

 

[Planet Reef]

Thanks Anthony!!!

This is Curtswearing (Planet Reef is the work account) and I'm temporarily doing something I swore I would never do in a million years.....I'm managing a LFS. Since the store is so new, there is a lack of bristleworms for clean-up and I would definately like to increase their population.

I don't even kill poisonous spiders so this is going to be a difficult decision for me to make. For the better good of the store, I now know I should rip a bristleworm in half. However, I know I can't do it personally and I know it will be difficult for me to ask someone else to do it. (To make this ultimately confusing, I keep mantis and I keep clean-up crews in my mantis tanks. I keep my mantis well fed and the clean-up crews last a long time as a result. However, I don't have a problem when one snail or one crab disappears). Can you say I'm full of contradictions?

Thanks again for the info.

 

[MAGDRL Mom]

Thanks Anthony!!!

...I don't even kill poisonous spiders...

Good thing - it's bad luck to kill a spider

 

[Anthony Calfo]

Curt... you are delightfully quirky like the rest of us, my friend

 

[Planet Reef]

Curt... you are delightfully quirky like the rest of us, my friend

LOL What a riot!!!