Urchin

[joyannbuskirk]

Can someone please tell me what this is on my Pin Cushion Urchin?
I love these guys! I have a big one and this little guy.

I keep taking these white things off their tops. They are both eating and their color and spines are good and they are eating like the little piggies they are.

Don't want to start worrying.

 

[bluemon]

A piece of rubble?

Urchin will often go around and pick up things

 

[gbroadbridge]

Can someone please tell me what this is on my Pin Cushion Urchin?
I love these guys! I have a big one and this little guy.

I keep taking these white things off their tops. They are both eating and their color and spines are good and they are eating like the little piggies they are.

Don't want to start worrying.

Urchins wander around tanks collecting camouflage.

Some folks make 3D printed hats for them to carry around.

Yours has only just started the journey :-)

Mine thoughtfully collects tufts of algae at the moment.

 

[joyannbuskirk]

A piece of rubble?

Urchin will often go around and pick up things

I don't know if it is sand or small bits of coral.

 

[joyannbuskirk]

Urchins wander around tanks collecting camouflage.

Some folks make 3D printed hats for them to carry around.

Yours has only just started the journey :-)

Mine thoughtfully collects tufts of algae at the moment.

I don't know why they want to hide. My two are so pretty!

What do feed yours? Mine have cleaned most of the rocks, but I also feed them seaweed and algae wafers.

 

[gbroadbridge]

I don't know why they want to hide. My two are so pretty!

What do feed yours? Mine have cleaned most of the rocks, but I also feed them seaweed and algae wafers.

I've never fed them anything ... They're scavengers and in a normal tank will find plenty to eat.

If the tank is new, I'd just feed the fish more, rather than trying to directly feed a scavenger.

But, it's unlikely to do any harm - you do you :)

 

[PapaFishRocks]

Mine wears bubble algae as a hat.

I occasionally put a nori sheet for my urchin. But really not necessary, if they have algae to graze on

 

[SayrinaDVM]

I don't know why they want to hide. My two are so pretty!

Many sea urchin species tend to collect things like shells, rocks, and algae and "hold" them over their upper body using their tube feet. It's called a covering reaction or covering behavior, and it's theorized to have multiple possible purposes apart from camouflage; one of the more widespread theories is that the objects provide protection from UV radiation, but other hypotheses include protection against predators and dislodgement by strong currents (since the objects would add weight).

In case you're interested, here are some links to papers (full-text available). It's really quite interesting :)

Ziegenhorn, Morgan A. “Best Dressed Test: A Study of the Covering Behavior of the Collector Urchin Tripneustes gratilla.” PLoS One 11.4 (2016): e0153581.

Dumont, Clément P., et al. "Multiple factors explain the covering behaviour in the green sea urchin, Strongylocentrotus droebachiensis." Animal Behaviour 73.6 (2007): 979-986.

 

[BonnieB]

At the moment my urchin has a little tiny snail shell it’s carrying but last week it had that AND what looked like a plastic cap, the kind that seals liquids so they don’t leak out of a bottle, as well. This is camouflage and they will pick up whatever isn’t nailed down. If you don’t want it on there, like if it’s one of your coral, then take it off. It will find other things to put on top!

 

[PapaFishRocks]

Many sea urchin species tend to collect things like shells, rocks, and algae and "hold" them over their upper body using their tube feet. It's called a covering reaction or covering behavior, and it's theorized to have multiple possible purposes apart from camouflage; one of the more widespread theories is that the objects provide protection from UV radiation, but other hypotheses include protection against predators and dislodgement by strong currents (since the objects would add weight).

In case you're interested, here are some links to papers (full-text available). It's really quite interesting :)

Ziegenhorn, Morgan A. “Best Dressed Test: A Study of the Covering Behavior of the Collector Urchin Tripneustes gratilla.” PLoS One 11.4 (2016): e0153581.

Dumont, Clément P., et al. "Multiple factors explain the covering behaviour in the green sea urchin, Strongylocentrotus droebachiensis." Animal Behaviour 73.6 (2007): 979-986.

The current leading theory widely accepted by most marine biologists…..

Urchins just look really good in hats.

 

[Gumbies R Us]

How is your urchin doing today?

 

[mumra]

A piece of rubble?

Urchin will often go around and pick up things

I 2nd this. Mine picked up a frag that I hadn't glued down yet and carried it around for a bit. I wish I had taken a pic.