I'm not completely versed in the methods used for shocking. But they add an small electric current to stun the fish. Purportedly it does not hurt them. This allow a counting and measurement to check on survival rates and for other research.
Really. They stun the fish. I had no idea they do things like that. I guess as long as it doesn't hurt the fish & it's in the name of conservation IT'S ALL GOOD.
This a practuce done by the DEP and Fishery biologists to asses the abundance as well as growth patterns of this fish in the body of water. It is supposed to not harm the fish in terms of mortality or future growth, Rather is it used to assess to overall staus of the fish population and determine if the water body would benefit from certain restrictions in fish take.