We are living in the Anthropocene, an era being defined by global mass extinctions caused by humanity. While on-going and impending extinctions of birds and other terrestrial vertebrates gain the most attention, the situation with freshwater fishes (and other freshwater organisms) is as bad or worse, partly because many freshwater extinctions are nearly invisible events, hidden by murky waters (Moyle and Leidy 2023).
California’s only native sunfish, the Sacramento perch, survived catastrophic floods in the 1860s and was so abundant that it was a regular staple in San Francisco’s markets before invasive species decimated its population.
From climate change to species loss and pollution, humans have etched their impact on the Earth with such strength and permanence since the middle of the 20th century that a special team of scientists says a new geologic epoch began then.
Called the Anthropocene — and derived from the Greek terms for “human” and “new” — this epoch started sometime between 1950 and 1954, according to the scientists. While there is evidence worldwide that captures the impact of burning fossil fuels, detonating nuclear weapons and dumping fertilizers and plastics on land and in waterways, the scientists are proposing a small but deep lake outside of Toronto, Canada — Crawford Lake — to place a historic marker.
After years of drought, salmon in Northern California are facing extinction. Conservation groups in the region have drafted a water management plan that, if adopted, would send less water to Central Valley farmers and keep more cold water for fish.
Last week, fishery advocates in Northern California submitted their temperature management plan to the State Water Resources Control Board. They want to change water operations in the Shasta, Trinity, Sacramento and Lower Klamath Rivers so the region’s salmon runs have enough cold water to survive.
Conservation groups said 80 species were known to have gone extinct, 16 in the last year alone. Millions of people rely on freshwater fish for food and as a source of income through angling and the pet trade. But numbers have plummeted due to pressures including pollution, unsustainable fishing, and the damming and draining of rivers and wetlands. The report said populations of migratory fish have fallen by three-quarters in the last 50 years.
More than a million species are at risk of extinction globally, including hundreds in California. That’s what the United Nations revealed on Monday.“The rate of global change in nature during the past 50 years is unprecedented in human history,” the authors wrote in a summary of the report, which compiled of thousands of scientific papers. In California, there are around 300 species at risk and 346 species in California, Nevada and Southern Oregon combined. A handful of plants and animals have already disappeared from the state, such as the Santa Barbara song sparrow and the the California subspecies of the Grizzly Bear.
The Water News Network is San Diego County’s source for water news and information.
