A daily compilation of significant news articles and comment
October 30, 2007
3. Watersheds
SALMON RUNS:
Effects of fires on plant, animal life worry experts - LA Daily News
DELTA ISSUES:
Editorial: Forming a vision; Balanced approach to Delta touted -
SALMON RUNS:
San Francisco Chronicle – 10/30/07
By Jane Lay, staff writer
This year's
By this time, usually tens of thousands more fish are being hooked by fishermen or are swimming through the Golden Gate to the tributaries of
Yet commercial fishermen who hunt for salmon in the ocean from
Fisheries biologists in Northern California who count the salmon that return up the American, Feather and
The salmon run could just be a little late this year, say state Fish and Game Department officials. On the Klamath and
The exact cause of the apparent drop in fall-run salmon is not yet clear, although some experts blame the way the state manages its water supply in the Sacramento-San Joaquin River Delta. Rushes of fresh water can signal fish to start migrating upstream, but meager flows also can hurt the survival of baby fish that eventually will return as adults. Low levels of krill, tiny marine invertebrates that the fish eat, also could be to blame, experts said.
In tributaries like
And on the
The Pacific Fishery Management Council, a regulatory body that sets limits on commercial fishing, had predicted a lackluster year for the
Zeke Grader, executive director of the Pacific Coast Federation of Fishermen's Associations, said the low fish counts are particularly worrisome because of the extra limits placed on fishing in recent years. Those limits were specifically aimed at boosting the number of fish that return to spawn on the
He blamed problems with moving water around the delta. The lack of krill in the ocean may have exacerbated the meager runs, he said.
The Sonoma County Water Agency, which this summer urged growers and residents to cut water use by 20 percent due to dry conditions, issued a statement Monday decrying the dearth of salmon returning to the
"Right now by this time in the year, we should have about 500 fish" passing the counting equipment at
The water agency is concerned that people are fishing at the mouth of the
Seabird expert Bill Sydeman, who recently founded the Farallon Institute for Advanced Ecosystem Research in
The conditions that salmon face in their first and second years have a bearing on whether they live to spawn at age 3.
Krill numbers were lower in 2006 and 2005 than they had been in 2001 and 2002, for example, Sydeman said. "It's not surprising to me that there are low salmon returns in 2007."
Oceanographers at the National Oceanic and Atmospheric Administration have been studying ocean conditions for decades. They link good years for salmon with vigorous upwelling of cold, deep, nutrient-rich water to the ocean's surface and the influx of cold Alaskan waters that bring in krill and other sea life.
This year the upwelling and transport of cold Alaskan waters were strong. Then the mixing slowed down. The surface water has been warmer than usual in the California Current, the swath of water moving between
"We're trying to understand what's going on out there," said Frank Schwing, an oceanographer with NOAA's
The scientists are trying to figure out whether there is a regime of cold and then warmer-water decades - or whether global warming could be throwing off the predicted regimes.
"One of the ideas is that global climate change will introduce greater extremes and much more variability into the climate. In reality, it's going to take a couple of decades. Then we can look back and see what the patterns were," Schwing said. #
http://www.sfgate.com/cgi-bin/article.cgi?file=/c/a/2007/10/30/MNAAT2VTR.DTL
Effects of fires on plant, animal life worry experts
LA Daily News – 10/29/07
By Alex Dobuzinskis, staff writer
The cough-inducing haze eventually will clear, but
And in areas especially hard hit by fire, chaparral might never grow back, making it tough for other plants and animals within a charred, altered ecosystem.
"If you have too-frequent fire, your vegetation may not recover from fire and you can end up losing species," said Scott Morrison, a scientist with the Nature Conservancy. "A lot of the natural environment will recover on its own. What we want to be on the lookout for are those places that are going to need some help."
With nearly two dozen wildfires burning in recent days,
After a wildfire, officials always prepare for the threat of mudslides on hills denuded by the flames.
"In terms of watersheds, erosion is a big worry if you've got hillsides without live vegetation," said Bill Rukeyser, a spokesman for the State Water Resources Control Board.
And if too much nutrient-rich ash and silt gets into waterways and out to the ocean, it can cause algae to grow, which hurts fish, Rukeyser said.
To prevent the threat of erosion and runoff, workers in the coming weeks will put down sandbags or turn fallen trees sideways to slow water flowing downhill. In U.S. Forest Service land, some of the same firefighters who were battling the flames will be setting up bales of hay to prevent runoff.
In
The Tecate cypress, a rare tree found in the
But for other species, the news might not be so dire. In fact, the wildfires could be a boon.
Coyotes often eat smaller prey that has been left disoriented by flames. A bird called the rock wren has been known to settle in areas stripped of plants and trees, nesting in rock outcroppings.
"Some things die, but then other species benefit and probably their populations go up," said Ian Swift, director of the
Condors seem OK
Wildlife managers were particularly concerned about populations of big-horn sheep and a few young
Some plants called "fire followers" will grow back by spring in areas that have burned, Swift said. Larger shrubs will grow back within five years, he said.
The California Department of Fish and Game will evaluate the burned areas, using satellite images and aerial photos to determine whether anything should be done to help species affected by the fires, said Harry Morse, a spokesman for the department.
Meanwhile, in heavily populated coastal areas, fires have been occurring too frequently, and that is harming the environment, experts said.
Unable to grow
Near
"Increasing fire frequency causes increasing fire frequency," Goode said.
Plants that emerge after a fire don't hold the soil as well as chaparral, which leads to erosion - especially with heavy rain - and harms rivers and streams.
"So the whole ecosystem starts to really deteriorate," Goode said.
A similar process of vegetation changing to more flammable plants has been at work along coastal
"It is a really serious condition from an ecosystem point of view," said Pepperdine professor Stephen Davis, a plant ecologist who has studied the process.
While the ash from burned vegetation is relatively clean, officials warned that burned homes could be toxic and include asbestos.
"Any structure that is burned, it's a good idea to assume the resulting ash has hazardous material," Rukeyser said.
As for the air quality, the health threat will be nearly eliminated within days of the fires being put out, South Coast Air Quality Management District officials said. Winds eventually will blow the bad air east over the
On Monday, the AQMD said air quality had improved in most areas, but that it remained unhealthful near the remaining wildfires.
And while some blame the wildfires for all the environmental hazards that have resulted, some think we need more fires to let nature take its course.
Richard Minnich, a geography professor at the University of California, Riverside, argues that in Baja California, where firefighters purposely don't battle wildfires as hard as in Southern California, frequent but less dramatic blazes thin out the vegetation and prevent the kinds of destruction seen here in recent days.
Minnich advocates letting wildfires burn out naturally.
"Look, fire is inevitable, it's like breathing - in fact they're the same process, it's called oxidation," he said. "The public has to understand this process is going to happen." #
http://www.dailynews.com/search/ci_7316668?IADID=Search-www.dailynews.com-www.dailynews.com
DELTA ISSUES:
Editorial: Forming a vision; Balanced approach to Delta touted
A promising vision of the Delta's future is taking shape, thanks to a panel of experts appointed by Gov. Arnold Schwarzenegger.
The Delta Vision blue ribbon task force is taking a balanced approach, strongly urging protection of the Delta ecosystem as well as ensuring the critical water supplies that the state's economy relies on.
However, to both protect the threatened Delta and still supply enough water for urban and agricultural use, some significant changes in water policy must be made.
No longer can increasing supplies of water be sent to the Central Valley and
The panel understands that if the state is to reduce its reliance on the Delta, greater regional self-sufficiency will be needed throughout
But the task force also recognizes that sufficient and dependable supplies of fresh water cannot be made available without new storage. The panel favors both in-ground aquifers and above-ground reservoirs, which the governor advocates.
The purpose of the new reservoirs would be to capture water during the wet months, when there is the least damage to the environment. Then the water must be efficiently moved to areas where it is needed.
The panel believes that improved conveyance must be constructed, such as an aqueduct. However, building an aqueduct alone without new storage capacity would threaten the Delta environment, according to the draft report.
That was the chief argument against the controversial
If the Delta environment received top priority and there were greater storage capacity, a modest-sized aqueduct to send water southward would not pose a threat to the estuary.
Additionally, the task force said that housing should be sharply restricted in the Delta. That makes sense for a number of reasons. Building homes in floodplains is a risky business that increases the state's liability. New superlevees built to protect developments put pressure on older ones protecting current neighborhoods.
The blue ribbon task force is fine-tuning its draft report on the Delta and Suisun Marsh and must make recommendations to the governor by Jan. 1. Next year, the hard part begins, as the panel devises an implementation plan.
Those plans are bound to affect
Last week, Solano supervisors approved spending $200,000 to hire consultants and lobbyists to help keep track of the proposed Delta changes and to makes sure Solano's concerns are known and addressed. It's a smart move, and one that probably should have been made months ago, considering the county is competing with at least 219 other government agencies that have some sort of jurisdiction over the Delta.
Hammering out a single vision for the Delta is no easy task. But the draft plan is on the right course in many key and controversial areas, and it presents the best opportunity so far for protecting the Delta and assuring dependable supplies of fresh water for urban, industrial and agricultural use. #
http://www.thereporter.com//ci_7320659?IADID=Search-www.thereporter.com-www.thereporter.com
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