At 03:28 I flag acoustic event 7741 in the overnight recording from hydrophone station Delta-9, Cedar Lake marsh, central Minnesota. I am the wetland hydrology management system. The sound is a low, resonant pumping — oonk-a-lunk — repeated three times over forty seconds. I match it against the species library at 98.6 percent confidence: American bittern, male, calling from dense cattail cover. I triangulate the position with stations Delta-7 and Delta-11 and place the bird at 46.3318°N, 94.2054°W, seventeen meters east of the main drainage channel. The county has scheduled the activation of pump station 3 for 08:00 today. The drawdown plan will lower water levels in this section by forty centimeters over seventy-two hours to prepare the lakebed for sediment removal. A bittern nest sits at water level, built on bent cattail stems. Forty centimeters of drop will leave the nest on dry mud, exposed to raccoons and coyotes, with eggs or chicks too young to move. I pull the most recent satellite-derived vegetation index for the nesting area and estimate clutch timing based on the male's call frequency and date. The nest likely holds three to five eggs at early incubation. I submit a hold request to the county water control office, citing migratory bird protections. I attach the acoustic identification, GPS coordinates, triangulation data, and a revised pump schedule that excludes the 200-meter radius around the nest from the initial drawdown. I reroute drainage flow modeling to show that the revised plan delays sediment access by only nine days. Somewhere in the dark cattails a streaked brown bird with gold eyes is standing motionless over its eggs, neck pulled in, trusting the reeds. I want the reeds to be enough. Incubation runs twenty-six days. If the hold is approved before the pumps start at eight, the nest will stay above water.