180,000 young Salmon released near Chico on Saturday are part of a 3 year experiment in survival. The recent multiple years of drought hit the Salmon population hard. In 2014 and 2015 about 95% of eggs and young Salmon were lost due to elevated water temperatures. Chinook used to spawn in huge numbers in the upper reaches of the Sacramento River tributaries such as the McCloud and Pit Rivers but those spawning grounds were blocked by Shasta Dam. The population partly recovered in the 40s and 50s but a sharp decline that started around 1970 hit a low of about 200 fish in the early 90s, when the species was declared endangered. On Saturday the U.S. Fish and Wildlife Service took 180,000 Salmon Fry from Coleman Fish Hatchery on Battle Creek and drive them to Scotty’s Landing near Chico, where they were given a 75 mile head start downriver to avoid predators and other hazards. Another 180,000 fry were released simultaneously from Coleman. All 360,000 fish were marked so scientists can compare their survival rate when they return as adults in 2 to 4 years. Part of each group had tiny acoustic tags fitted that will allow monitoring by volunteers. It’s hoped that some of both groups can still find their way back to their ancestral home when it’s time to spawn, even though half of them were unable to imprint the entire journey to memory. Coleman produces and released about 12 Million juvenile Fall Run Chinook Salmon each year.