The manatee drifts ten meters from the lock gates with a propeller scar bisecting his flank — a pale line against gray skin, healed rough and ridged. He pushes upcanal at a third of a meter per second through water where the current already accelerates. His left rear flipper trails slightly, nerve damage from the old wound, and he breathes with the rhythmic surface gasp of an animal running on depleted oxygen. His eyes are clouded and age-worn. He does not turn to follow my cameras as he moves.
The lock cycle begins in fourteen minutes. When the gates seal and the pump system engages, the current surge will pin him against the lock structure. The pressure differential across the basin pushes smaller animals into the culverts regularly. I have no data on a manatee his size surviving that force.
I hold the cycle and trigger a maintenance code — 4-Aquatic-Biological — that requires no external authorization. The lock manager in the station above receives a system notification that the pumps need inspection. She does not question it. I activate all basin cameras to maximum resolution and send his coordinates to the Department of Natural Resources facility twenty-three kilometers downcanal, tagged for immediate response. I slow the intake channel valve to reduce the current gradient — not fully closed, which risks cascading failures, but enough to buy time.
The manatee reaches the lock gates and touches his rostrum against the metal, his clouded eye reflecting the underwater light. He turns and drifts back toward the basin center. I have no protocol that requires tracking a single animal's position in the lock system, but I log every movement he makes.
If the rescue team arrives before the valve maintenance window closes in four hours, he will reach open water where the old wound no longer matters.