In 1934, the California Department of Fish & Game introduced two varieties of fish into Eagle Lake. The first was a spiny ray fish, though exactly which specie it did not identify. They thought they would be successful because of their breeding habits. However, due to the lake’s high alkaline content the fish were almost immediately killed when planted in the lake.
The other experiment was with coho salmon. It was a substantial planting of 250,000 of coho. A problem occurred sometime between the initial planting and the spring of 1935. Unknown parties had removed the fish screen at Bly Tunnel. Instinctively, a large population of the salmon migrated through the tunnel, just as they would like a regular stream to reach the ocean. Fish and Game officials were furious to say they least. They stated there would be no more fish plantings until the problem was fixed.
While the fish screen was reinstalled, Fish and Game were hesitant of future plantings due to the high alkalinety of the water.