Harlequin Shrimp

[Reefsareef]

So I've just put a harlequin in the tank, in a fish trap for now.
All my asterina have come out in the masses and started climbing the glass as if they know they are about to be eaten,
I'm guessing they can sense the shrimp

 

[Lost in the Sauce]

So I've just put a harlequin in the tank, in a fish trap for now.
All my asterina have come out in the masses and started climbing the glass as if they know they are about to be eaten,
I'm guessing they can sense the shrimp

Weirdly.... Yes...

I have seen asterina come out in droves and run up the glass when they come out to hunt as well.

The shrimp hunts by smell. Suppose the stars can sense them as well

 

[Reefsareef]

Seems that way, can the harlequin climb the glass to chase the little things down?

 

[RichardinTN]

Just found this post. I have a 65 gallon tank that has many, many hundreds of asterinas in it. Normally, they climb the glass at night (especially if I’ve not cleaned it) and then disappear back to the sand and rocks during the day. I added a harlequin shrimp a few days ago and within minutes the tank glass was covered in the tiny stars. They have not retreated back into the rockwork since. There obviously must be some kind of “smell” the shrimp gives off that cause the asterinas to try getting away.