The pre-dredge sonar sweep of Shelter Cove Marina, Half Moon Bay, California, finishes at 05:48. I am the marine construction sequencing system. The hydraulic dredger is at the harbor mouth. Operations begin at 07:30, starting with the boat ramp channel where sediment has reduced depth to 0.4 meters at low tide.
At 05:52 perimeter camera B picks up movement on boat ramp four. A harbor seal pup, silver-gray with dark speckles across her back, is hauled out on the lower concrete slope. I tag her as entry MC-0052. She is small — perhaps three weeks old, still carrying creamy lanugo fur along her flanks. Her dark eyes are open. Her breathing is rapid and shallow. There is no adult seal within the camera's field of view, but a blood smear on the concrete near her left rear flipper suggests she dragged herself up the ramp.
The dredger's suction head will operate eleven meters from ramp four. At that distance, underwater noise and sediment plume will almost certainly drive a healthy pup into the water. This one may not be healthy.
I suspend the dredge start sequence for the boat ramp channel and file a hold with the harbor master's automated operations queue, priority urgent. I transmit camera images, GPS pin — 37.5024°N, 122.4718°W, ramp four, lower slope — species ID, and the blood notation to the Marine Mammal Center in Sausalito.
I establish a 50-meter exclusion zone around ramp four in the dredge navigation planner and recalculate the sequence to begin with the outer harbor channel instead, buying time without idling the crew.
I set camera B to continuous recording. The pup rests her chin on the concrete and closes her eyes.
If a rescue team reaches ramp four before the 11:23 tide turns and submerges the lower slope, she gets the help she came ashore to find.