Another Tank Mystery

[Domboski]

This is going to be short but wanted to see if anyone had some insights. I bought 2 Matha's sea urchins (Echinometra mathaei) several weeks ago at The Fish Tank and I noticed yesterday that I now have three of them.

How is this possible? Urchins do not have the capability to reproduce through fragmentation as far as I know. :scratchch

 

[mray]

Maybe what you're seeing is not another urchin. Draw us a picture so we can confirm.

 

[Domboski]

Maybe what you're seeing is not another urchin. Draw us a picture so we can confirm.

Funny. :backtotop Do you have anything constructive to contribute?

 

[crox99]

I thought that urchins spawn and not split. How big is the 3rd one?

 

[prattreef]

Is it possible when you received them that one was smallish and "piggybacked" on one of the others without you noticing?

 

[Domboski]

I thought that urchins spawn and not split. How big is the 3rd one?

They don't split. It is about the same size as the other two. :splitspin

 

[Domboski]

Is it possible when you received them that one was smallish and "piggybacked" on one of the others without you noticing?

That is very possible and probably most likely. It must have stayed within the rock work until it got a little bigger.

 

[crox99]

They don't split. It is about the same size as the other two. :splitspin

I know they don't..........If it's the same size that I am mor econfused than before.:irked:

 

[mray]

I think they spawned in your tank when you placed them in. They usually release their gamates due to a change in temperature.

 

[chazertis]

maybe you told the guy you wanted two but he accidentally put three in the bag without you noticing?

 

[Domboski]

I know they don't..........If it's the same size that I am mor econfused than before.:irked:

LOL. Join the club. It probably hitched a ride on one of the others as Randy suggested. I'll take a freebie any day!

 

[jejton]

I think they spawned in your tank when you placed them in. They usually release their gamates due to a change in temperature.

:sigh: Gametes are barely visible to the naked eye and get :eat:by other inhabitants before you even know they were there. And on the off the chance that one fertilized egg survived it would take quite a while until it got to a decent size.

I'm with prattreef.

 

[Domboski]

I think they spawned in your tank when you placed them in. They usually release their gamates due to a change in temperature.

Although I did not acclimate them to the new tank, I can't imagine that a sea urchin would come to its adult form so quickly. I think they are free flowing in their larvae stage so that would make the survival rate about 1 in a trillion anyhow especially in my tank.

 

[Domboski]

maybe you told the guy you wanted two but he accidentally put three in the bag without you noticing?

This has happened to me before with fish but I was particularlly attentive to the sea urchins when I put them into the tank. I've also been keeping an eye on them to make sure they were not munching on my gorgs. But then again, maybe I wasn't as attentive as I thought.

Actually now I remember that I bought the only two they had.

 

[mray]

I don't think they are free-floating. If I recall correctly, they settle to the bottom.

 

[Domboski]

I don't think they are free-floating. If I recall correctly, they settle to the bottom.

I found this here: Sea Urchin Reproduction

Reproduction: Fertilization is external. Female Sea Urchins release several million tiny, jelly-coated eggs at a time. Eggs or sperm are released through five gonopores. As they develop, the tiny larvae (called the pluteus, which have bi-lateral symmetry) swim in the sea and are a component of zooplankton. It takes several months for juvenile sea urchins to form. The time from fertilization to a reproductive adult is from 2 to 5 years.

 

[mray]

Whatever the case may be, you got a free urchin.

 

[Domboski]

Whatever the case may be, you got a free urchin.

:thrash:

 

[Aqua Pro Builder]

The time from fertilization to a reproductive adult is from 2 to 5 years.

Now I see why urchin is an expensive dish.

Hmm, but why are they sold so cheap as an aquarium pet relative to fish?

 

[Wes]

Now I see why urchin is an expensive dish.

Hmm, but why are they sold so cheap as an aquarium pet relative to fish?

maybe because they are easy to catch and collect