9/30/21

Biden administration moves to save endangered dinosaur

Pallid sturgeon are living dinosaurs but when the Missouri River dams were built it sealed the fate of the now endangered fish. Scientists and the US Army Corps of Engineers have learned that unless newly hatched pallid sturgeon have several hundred miles of unimpeded waters they cannot survive. 

Rivers often disperse the extra sediment from behind a dam within weeks or months of dam removal. Removal of the Fort Edward Dam on New York’s Hudson River released so much contaminated sediment that the river was later named a Superfund site. A similar fate would befall the Missouri River if dams were not dredged before being decertified and removed; but, migratory fish would recolonize newly accessible habitat within a matter of days. The Corps has cancelled Spring Pulses on the Missouri River not just because of low flows but because the silt is so poisonous it would kill the very species it says it's trying to preserve. 

On the east side of the Continental Divide Canadian miner Barrick operates the Golden Sunlight Mine near Whitehall, Montana. Effluent from that mine goes into the Jefferson River, a tributary of the Missouri and much of it lies in repose within Canyon Ferry Reservoir. 

Below the Missouri River dams pallid sturgeon are showing signs of recovery but above? As pallid sturgeon goes extinct in the upper Missouri River zebra mussels are spreading through the system.
Under its chosen alternative, when reservoir water levels allow, the Corps would request that Fort Peck Dam begin increasing releases in April to see if mimicking spring runoff will attract pallid sturgeon into the Missouri River. Beginning on April 16 — only when Fort Peck Reservoir’s elevation is at 2,227 feet and other downstream and runoff factors align — flows would be increased by 1,700 cubic feet per second each day until the peak flow at the Wolf Point gauge reached 16,000 cfs. That flow would be held for three days and then gradually decreased before being boosted in late May to 28,000 cfs. The peak flow would be held for three days, and then gradually decreased to 8,000 cfs and held there through mid-July. On the Yellowstone River, a tributary to the Missouri, the Bureau of Reclamation is reconstructing Intake Dam — an irrigation impoundment — to include a two-mile-long bypass channel in hopes pallid sturgeon and other native fish will have access to another 165 miles of river above the dam to successfully spawn. [Plan finalized to test boosting Fort Peck Dam releases to encourage pallid sturgeon to spawn]
Nearly two dozen more species were declared extinct Wednesday.

ip photo: the Corps announces its presence near the headwaters of the Boulder River in Jefferson County, Montana.

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