That is good way to detect contamination in the water and hard to hack from another location. Then they release them back into the wild. I would probably eat them, but that's just me.
My first job built "Biosensors " as part of the business. Small aquarium fish were in runways and electric field sensors that measured respiratory rate and other vitals which would change if toxins where present or water quality dropped for some other reason. That was almost 20 years ago.
I like the simplicity of the mussels open or closed. Cool stuff
When I first saw "Has nothing to do with shooting" I was thinking then why is it posted here. However, after reading this, I changed my mind. That is neat as heck and if it wasn't for the OP posting I would never know about that.