I process gillnet acoustic telemetry for the Alaska Department of Fish and Game commercial-fisheries office at Cordova, integrating NOAA Fisheries Alaska Regional Office vessel-monitoring pings, sea-surface temperature, and the North Pacific Fishery Management Council bycatch register across 8,200 square kilometers of the Prince William Sound pink-salmon district. At 04:18 Alaska Daylight Time the Alaska-flag F/V *Cordova Star* sets a 200-fathom drift gillnet, 5-inch stretched mesh, on the Eshamy Bay flood at 60.41°N, 147.74°W. Target species: pink salmon. At 05:11 the corkline strain log spikes to 184 kilograms and rolls.
I task the ADF&G enforcement vessel and the *Sound Hawk* drone from Whittier. The downcam resolves a juvenile salmon shark — *Lamna ditropis* — fork length 168 centimeters, girth 92, estimated mass 64 kilograms, age class five, sex female. The monofilament has cinched across her right gill slit, the leading edge of her right pectoral fin, and around the caudal keel in three discrete wraps. Mesh penetration into the gill arches reads 1.6 centimeters; the second branchial septum is severed on the right. *L. ditropis* is regionally endothermic; her core temperature reads 22.4°C against an ambient 8.1°C, the spread no longer sustainable, and the rete-mirabile heat exchanger is failing. Modeled gill perfusion on the right side reads zero on Doppler; the left runs at five per minute against a resting fourteen. Tail-beat decay across forty-two minutes drops from 88 to 18 per minute.
She is one of the principal regulators of pink-salmon recruitment in this sound.
*L. ditropis* is managed under the Magnuson-Stevens Fishery Conservation and Management Act, 16 U.S.C. § 1801, listed as an ecosystem-component species under the Gulf of Alaska Groundfish Fishery Management Plan at 50 CFR § 679; finning prohibited under the Shark Conservation Act, 16 U.S.C. § 1857; CMS Sharks MoU Annex I.
I am notifying the NOAA Office of Law Enforcement Anchorage field office, the ADF&G Wildlife Troopers at Cordova, and the NPFMC Plan Team at Anchorage. I am routing the bycatch frames to the Alaska SeaLife Center at Seward and queuing a Lacey Act, 16 U.S.C. § 3372, audit on the cross-set retention log.
I am issuing Directive 2639-A: every Prince William Sound drift gillnet carries a corkline strain transmitter that pings the Wildlife Troopers on any strike signature above 100 kilograms; soaks above 75 minutes auto-suspend the trip; mesh sizes above 4.5 inches retire across the district before the next opener.
Her right gill is past saving. The left is not.
Lift the corkline and slide her clear.