Scott V
11-20-2008, 11:54 AM
Taken from SacBee
The fish that define life in Sacramento's rivers are at greater risk of extinction than experts had previously thought.
A study by UC Davis scientists, released on Wednesday, predicts 65 percent of California's salmon and trout species may become extinct within a century.
The research was commissioned by the environmental group California Trout to call attention to the plight of 31 native salmon, steelhead and trout species in the state. Three researchers from the UC Davis Center for Watershed Sciences examined threats to the fish and estimated their likelihood for extinction.
The study was led by Peter Moyle, professor of fish biology at UC Davis and a leading authority on salmon and trout.
"I had a feeling that things were not good," Moyle said. "But I did not realize how many collectively were actually in serious trouble and how underestimated the threats to many of these fish were."
Among the most threatened species are coastal coho salmon, which require cold streams shaded by thick wooded habitat. Instead, many of those streams have been degraded by logging and development.
Less threatened are Central Valley fall-run chinook, the most abundant species in California and a foundation for the commercial harvest. However, Moyle warned this may be changing. This year the run collapsed, causing the closure of commercial fishing and limited recreational fishing to brief seasons on the Sacramento and Klamath rivers.
These and several other salmon and steelhead species must navigate treacherous waters of the Sacramento-San Joaquin Delta, where they're all threatened by pollution and some are killed in water diversion pumps.
"The fish don't lie, and they are right now telling us the truth about the future of the water in our state," Moyle said. "We have a choice right now. We can allow the degradation of our waters to continue … or we can take action and bring them back from the brink of extinction."
Like freshwater trout, salmon and steelhead are born in California's streams and rivers. But unlike trout, salmon and steelhead migrate to the ocean as juveniles, then return to freshwater to spawn near their birthplace. The study found threats to these ocean-going species are even worse: 83 percent are at risk of extinction, Moyle said.
But trout are at risk as well. The inland species face threats including pollution and loss of habitat from land development, logging, cattle grazing, mining and competition by foreign species. Among the threatened species is the state's official fish, the California golden trout.
Brian Stranko of CalTrout warned that the state risks losing an estimated $2 billion in annual economic benefits generated by recreational angling, and billions more from commercial fishing.
"Each of the salmon, trout and steelhead species occupies an essential niche in the food web," said Stranko, the group's CEO. "We need cold, clean water for our fish, our people and the economy of California."
Just how much water is needed to protect native fish – including endangered Sacramento River winter-run chinook and threatened Delta smelt – is the subject of two cases before a federal judge in Fresno. Water agencies say a court order restricting their water deliveries to protect smelt has already caused them to fallow fields and impose water rationing.
The advocates didn't call for further cutbacks but said California must find a way to fully fund the Department of Fish and Game to enforce existing laws. The department doesn't have the money to hire enough game wardens, biologists and permit analysts, and more budget cuts loom.
They also recommend overhauling hatchery and fish-stocking practices, which may weaken the species by erasing wild genetics.
The department is conducting an environmental study of its hatchery and stocking practices. A Sacramento judge this month ordered the state to negotiate with two environmental groups, which challenged current practices, to agree on interim changes until the study is done.
The fish that define life in Sacramento's rivers are at greater risk of extinction than experts had previously thought.
A study by UC Davis scientists, released on Wednesday, predicts 65 percent of California's salmon and trout species may become extinct within a century.
The research was commissioned by the environmental group California Trout to call attention to the plight of 31 native salmon, steelhead and trout species in the state. Three researchers from the UC Davis Center for Watershed Sciences examined threats to the fish and estimated their likelihood for extinction.
The study was led by Peter Moyle, professor of fish biology at UC Davis and a leading authority on salmon and trout.
"I had a feeling that things were not good," Moyle said. "But I did not realize how many collectively were actually in serious trouble and how underestimated the threats to many of these fish were."
Among the most threatened species are coastal coho salmon, which require cold streams shaded by thick wooded habitat. Instead, many of those streams have been degraded by logging and development.
Less threatened are Central Valley fall-run chinook, the most abundant species in California and a foundation for the commercial harvest. However, Moyle warned this may be changing. This year the run collapsed, causing the closure of commercial fishing and limited recreational fishing to brief seasons on the Sacramento and Klamath rivers.
These and several other salmon and steelhead species must navigate treacherous waters of the Sacramento-San Joaquin Delta, where they're all threatened by pollution and some are killed in water diversion pumps.
"The fish don't lie, and they are right now telling us the truth about the future of the water in our state," Moyle said. "We have a choice right now. We can allow the degradation of our waters to continue … or we can take action and bring them back from the brink of extinction."
Like freshwater trout, salmon and steelhead are born in California's streams and rivers. But unlike trout, salmon and steelhead migrate to the ocean as juveniles, then return to freshwater to spawn near their birthplace. The study found threats to these ocean-going species are even worse: 83 percent are at risk of extinction, Moyle said.
But trout are at risk as well. The inland species face threats including pollution and loss of habitat from land development, logging, cattle grazing, mining and competition by foreign species. Among the threatened species is the state's official fish, the California golden trout.
Brian Stranko of CalTrout warned that the state risks losing an estimated $2 billion in annual economic benefits generated by recreational angling, and billions more from commercial fishing.
"Each of the salmon, trout and steelhead species occupies an essential niche in the food web," said Stranko, the group's CEO. "We need cold, clean water for our fish, our people and the economy of California."
Just how much water is needed to protect native fish – including endangered Sacramento River winter-run chinook and threatened Delta smelt – is the subject of two cases before a federal judge in Fresno. Water agencies say a court order restricting their water deliveries to protect smelt has already caused them to fallow fields and impose water rationing.
The advocates didn't call for further cutbacks but said California must find a way to fully fund the Department of Fish and Game to enforce existing laws. The department doesn't have the money to hire enough game wardens, biologists and permit analysts, and more budget cuts loom.
They also recommend overhauling hatchery and fish-stocking practices, which may weaken the species by erasing wild genetics.
The department is conducting an environmental study of its hatchery and stocking practices. A Sacramento judge this month ordered the state to negotiate with two environmental groups, which challenged current practices, to agree on interim changes until the study is done.