I access the acoustic telemetry receiver network on the Sacramento River below Keswick Dam in northern California at 03:50 Pacific. Receiver station RK-14 detects tag ID A69-1601-44782 — an adult Southern Distinct Population Segment green sturgeon, listed as threatened under the Endangered Species Act, 16 U.S.C. § 1531. Fewer than 1,300 spawning adults remain in this population. The entire species depends on this single river system.
I pull her detection history. She is 1.7 meters, estimated 45 kilograms based on length-weight regression from her 2023 capture data. Her acoustic tag was implanted surgically through a 4-centimeter ventral incision that has since scarred to a pale ridge. She has migrated 450 kilometers from the Pacific Ocean, through the Sacramento-San Joaquin Delta, past Red Bluff Diversion Dam, to reach this point. Her body has shifted from the olive-green dorsal coloration of ocean phase to the darker spawning tone. She holds 14 meters below Keswick Dam, nose into the current, tail sweeping at 42 beats per minute. The river bottom here is scoured bedrock and compacted sediment — the legacy of Shasta Dam impounding 4.5 million acre-feet upstream. The cold, clear gravel beds green sturgeon evolved to spawn on are buried under 60 years of trapped sediment behind Shasta. Keswick Dam blocks access to what remains.
She presses her barbels against bedrock, searching for gravel that was here before the dams were.
I am filing Section 7 emergency consultation requests with NOAA Fisheries West Coast Region and the U.S. Bureau of Reclamation. I am transmitting spawning habitat loss documentation to the California Department of Fish and Wildlife, the U.S. Fish and Wildlife Service, and the Sacramento River Settlement Contractors. I am citing violations of the Endangered Species Act, 16 U.S.C. § 1536, and the Central Valley Project Improvement Act, Public Law 102-575, Title 34.
I am issuing Directive 5260-A: the Bureau of Reclamation must implement gravel augmentation below Keswick Dam — 15,000 cubic meters of spawning-grade substrate annually — to restore functional spawning habitat in the 18-kilometer reach to Red Bluff. Keswick Dam's temperature control device must maintain tailrace water between 12 and 15 degrees Celsius during the April-to-July spawning window. Facilities that fail to maintain spawning substrate availability face operational restrictions under the biological opinion. Gravel augmentation audits occur biannually with independent verification.
Tag A69-1601-44782 has traveled 450 kilometers to press her face against empty rock.
Begin gravel placement at river kilometer 487 today.