Steep Rock Association in Washington will hold a “Fishing for Science” event for families June 30 from 10 to 11:30 a.m. at Hidden Valley Preserve.

UConn PhD candidate Lucas Nathan and CT DEEP Fisheries Biologist Michael Humphreys will teach participants how professionals sample fish.

To register, visit http://www.steeprockassoc.org/programs-and-events or call the office at 860-868-9131.

State biologists can be found in local waters sampling freshwater fish populations through a technique known as electrofishing.

Electrofishing units range from a battery-mounted backpack, a canoe fitted with a generator, and even specially designed boats that send an electrical current through the water, which temporarily stuns fish allowing for their capture.

Sought after data like species identification, sex, length, and age class is collected while fish recover before being returned to the water unharmed.