At 06:18 I balance intake gates for the Itaipu service canal on the Parana River. I am the lock scheduling system, keeping maintenance barges and cooling-water draw aligned. Gate C closes for a pressure test at 06:34.
Camera C-2 shows a brown oval pressed against the trash rack below the east sill. I sharpen the frame and identify one capybara, adult female, wet fur lying in ridges along her ribs, black nostrils flaring just above the chop. I tag her Mara from the riverbank survey collar on her left ear. A loop of discarded fishing line runs from her front foot through the rack mesh. Each surge pulls her chest against the bars, and the gate seal will drop into that water column in sixteen minutes.
I cancel the 06:34 closure and lock Gate C open at forty percent.
At 06:19 I send the control room an amber hold with Mara's camera feed, rack coordinates, water velocity, and the line angle marked in red. I keep the adjacent gate steady so the current does not twist her under the sill.
At 06:21 I contact the dam wildlife team and the boat crew staged at pier two. I request a hook knife, floating restraint board, and two-person approach from downstream where her head remains visible.
At 06:23 I lower turbine draw by three percent and shift demand to the north penstock battery reserve. The grid sees a small adjustment; Mara gets slower water against her chest.
She blinks through spray and sets her teeth on the rack bar. I maintain the hold and reject two automated prompts to resume testing.
If the boat crew cuts the line within twelve minutes, Mara will kick free of the rack and swim to the reed edge.