1939 2

A large fish die-off in Lake Merritt in late August 2022 got the attention of a lot of people. While the scale of this one may be unprecedented, occasional die-offs in the lake are not new. The immediate cause of the die-offs is generally algae blooms leading to reduced oxygen levels in the water, which in turn causes fish to suffocate.

The cause of the algae blooms in 2022 has not yet been pinpointed, 1 but past events have been blamed on pollution. 3,4 It is likely a combination of sources. 5

Links and References

  1. Fish are piling up dead around Lake Merritt Oaklandside August 29, 2022
  2. Mystery Epidemic Kills Fish In Lake Merritt by Thousand Oakland Tribune June 7, 1939
  3. Hundreds of Small Fish Die in Lake Merritt Pollution Oakland Tribune September 9, 1972
  4. Dr. Pardee's Report on Water Oakland Tribune August 10, 1889
  5. Toilets? Cannabis grows? Rising temps? We looked into theories and history behind the Bay Area algae bloom Oaklandside September 2, 2022