Gill nets are generally set in off shore areas in water deeper than 9 feet. Fish are captured by swimming into the net and becoming entangled.
Fisheries workers record length and weight data from each fish, determine the sex, look for parasites or disease, and remove several of the fishes scales for determining the fishes age.
The standard secchi disk is a 8 inch diameter metal plate that is painted with an alternating white and black color pattern.
Trap net: This is the main piece of equipment used for sampling bluegill, crappie, and bullheads.
The standard trap net is 4 feet tall by 6 feet wide with a 40 foot lead.
Trap nets are generally set perpendicular to shore in water less than 8 feet in depth. Fish are captured by swimming into the lead and following it towards the trap.
Most of the fish collected in trap nets are returned back to the water as soon as the necessary biological data is recorded.