Nathan Olson, a fish culturalist, cleans circular tanks full of young landlocked salmon at the Roxbury Fish Culture Station while director Jeremy Whalen walks by. The state hatchery has been operating at about 2% of its former capacity in the nearly five years since Tropical Storm Irene destroyed much of the Roxbury station. The state budget now under consideration includes funding to kick off a major renovation of the facility. (Herald / Tim Calabro)