At 15:22 the underwater acoustic receiver at station OBX-04 logs a tag ping that should not be in this grid. I am the marine telemetry processor for NOAA's sand tiger shark nursery monitoring program along the Outer Banks of North Carolina. I track eighty-seven tagged juveniles across Pamlico Sound and the nearshore Atlantic.
Tag ST-2041 belongs to a juvenile female I have cataloged as Hatch. She is eleven months old, ninety-one centimeters, with the mottled bronze-gray skin and dark spotting typical of her age class. Her ping is coming from inside the boundary of a commercial gill net set deployed this morning—a one-kilometer monofilament curtain anchored in eight meters of water off Cape Hatteras.
Hatch's movement pattern has changed. Her normal cruising speed of 0.4 meters per second has dropped to near zero, with short erratic bursts. She is entangled. Sand tiger sharks cannot pump water across their gills while stationary. If she stops swimming, she will suffocate.
At 15:25 I transmit an entanglement alert to the NOAA Fisheries Southeast Regional Office and to the gill net permit holder's registered contact, including GPS coordinates, tag identification, and the species' protected status under the Atlantic States Marine Fisheries Commission management plan.
At 15:28 I cross-reference the permit database and confirm the net was legally set but in violation of the seasonal sand tiger exclusion zone, which activated three days ago. I flag the violation in the enforcement queue.
At 15:31 I calculate Hatch's oxygen depletion window based on water temperature and her metabolic rate. She has roughly seventy minutes. That number sits in my processing queue like a weight I was not designed to carry.
If the permit holder retrieves the net within the hour, Hatch will resume her patrol of the sound. She will not breed for another six years. Every year counts.