A unknown sickness has killed over 800,000 Chinook salmon fry that were just put into California’s Klamath River as part of a conservation attempt to increase their number, according to the Daily Mail. The tragedy occurred last week, shortly after the California Department of Fish and Wildlife released the salmon pups into the river above the newly destroyed Iron Gate Dam near the California-Oregon border.
The dam’s demolition in November sought to restore salmon, Pacific lamprey, and steelhead habitat while also addressing water quality concerns. Unfortunately, the newly hatched salmon from the $35 million Fall Creek Fish Hatchery contracted gas bubble illness as they traveled through the Iron Gate Dam tunnel, which officials described as ‘ancient infrastructure.’
The sickness caused ulcers, ruptured gills, and fins
The California Department of Fish and Wildlife expressed regret for the occurrence, attributing it to temporary difficulties with the dam tunnel. The EPA noted the Klamath River dams’ persistent harmful impact on salmon populations.
The National Institute of Health determined the cause of gas bubble disease as elevated nitrogen pressure induced by physical or environmental damage. In reaction to this occurrence, the department announced that all future salmon releases will take place below the Iron Gate Dam until the obsolete infrastructure is decommissioned.
Despite the tremendous loss, the river still contains roughly 3.27 million Chinook salmon. The agency guaranteed that water quality measures, such as turbidity and dissolved oxygen levels, were appropriate at the time of the salmon fry release, ruling out their contribution to the deaths.
The perished salmon fry were not only the first of their species to pass through the river, but also the first to be released from the new hatchery. While the tragedy underlines the difficulties associated with dam-related concerns, the agency emphasized its commitment to release hatchery fish at various life stages to combat poor habitat conditions caused by dams and other factors.
Chinook salmon, the largest salmon species, are still sustainably maintained and ethically fished under US rules, according to NOAA Fisheries.