Many California salmon populations should not survive the century: salt: NPR
Workers are preparing to release thousands of Chinook locusts in the Mare Island Strait in Vallejo, California, in 2014. New report denounces climate change, dams and agriculture as key threats to precious fish And emblematic, which is still at the heart of the robust fishing industry of the state.
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Workers prepare to release thousands of Chinook fingers in the Mare Island Strait in Vallejo, California, in 2014. A new report denounces climate change, dams and agriculture as the main Threats to precious and emblematic fish The core of the robust fishing industry in the state.
Justin Sullivan / Getty ImagesWild Chinook salmon, probably the most sought-after seafood item on the west coast, could simply disappear from California in a century, according to a report released Tuesday.
The authors, along with the University of California, Davis, and the California Trout Conservation Group, refer to climate change, dams and agriculture as major threats to fish Precious and emblematic, which is still at the heart of the robust fishing industry of the state.
Chinook salmon is a species at risk of extinction. Overall, California is home to 31 species of genetically distinct salmon and trout, 23 of which are expected to be extinct in the next century, according to the report.
The report, titled State of Salmonids II: Fish in Hot Water is an update of a 2008 assessment that made similar conclusions - except That nine years ago, the prospects were not so bad. At the time, the authors - among whom UF Fisheries Biologist Davis Peter Moyle, who works at the University's Cuvette Science Center, also contributed to the new report - have Concluded that five types of genetically distinct Californian salmon could disappear within the next five decades.
Now the 50-year outlook is three times worse, with 14 species and subspecies deemed likely to disappear if current trends continue. Although some factors affecting fish, such as degraded river habitat and excessive diversion to irrigation, can be reversed, the report indicates that climate change already underway could devastate salmon populations and Of California trout.
"As we began drafting the 2017 report, we found that new information and the increasingly evident impacts of climate change require us to rethink the measures used in the 2008 report to assess the status [of each species]"said Moyle, who wrote the New Report with UC Davis colleague Robert Lusardi and California Conservation Program coordinator Trout Patrick J. Samuel.
Salmon and trout depend on clean water and especially cold water. But as the Earth warms up, there will be less snow and cold water in the mountains where rivers begin, like the Sacramento and the Klamath. Many water courses become too hot for fish to tolerate or even dry up completely, during the summer months, the authors predict.
Agriculture can have similar impacts on watersheds, and in their 106-page report, the authors repeatedly cite food, marijuana, wine, Other crops as a major threat to California salmon and trout. Agriculture and grazing can hinder waterways with eroded sediments and chemicals. Crop irrigation also means pumping large quantities of water out of the rivers, which can disrupt patterns of salmon migration or fail in warm, shallow waters.
On the northern coast of California, in an area known as the "emerald triangle" for its marijuana production, Coho salmon - once thick in almost all small coastal streams south of Santa Cruz - is seriously threatened, according to the report. The authors estimate that more than 75 years ago, Coho spawned 100,000 to 300,000 each year in the coastal waters of northern California and southern Oregon. Today, fewer than 5,000 still swim upstream to lay and fertilize their eggs.
The Chinook Fingerling salmon is thrown into a square pen as they are being transferred from a truck to the Sacramento River in Rio Vista, California in March 2014.
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Northern California marijuana growers - whose culture was legalized at the end of last year - are known to suck dry creeks where Coho salmon spawn, especially in summer, when practically No rain falls in most of the state and producers become particularly dependent on irrigation.
Chinook salmon juveniles, on the other hand, spend only a few months in freshwater before migrating to the sea, making them less vulnerable to loss of domestic habitat . Yet, Chinook salmon - the only salmon species commercially caught and marketed in California - is not doing well either. According to the report, six of the eight distinct Chinook populations in California are likely to disappear.
While hundreds of thousands of Chinooks still spawn in California in a productive year, these precious fish are mainly hatchery products that fertilize salmon eggs in tanks and release babies in the Wilderness to several months. According to the authors, this life support system, although good for short-term fishermen, is bad for wild and self-sustaining salmon and steelheads. This is because hatchery fish often spawn wild fish, weaken genetic lines and blur the genetic distinctions between different populations.
California salmon is not necessarily total. The authors suggest restoring the riparian floodplains and coastal marshes, where young fish find abundant food. They also recommend concentrating conservation efforts on watercourses that come from mountain springs. These spring-fed streams will likely remain cold even if the planet warms, and they may be the only places where salmon will spawn in the future. Elimination of dams could also allow access to salmon at tributaries of cold water, according to the authors.
During a telephone call to the media on Tuesday, Curtis Knight, executive director of California Trout, said that native salmon could still be part of the culture, economy and The California diet in the future.
"We still have time, and we are optimistic with an effort, we can have a future that involves these fish," he said.
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