Researchers from NOAA’s Northwest and Southwest Fisheries Science Centers are comparing data on the low food production of the California Current in 2005 that occurred when this year’s returning salmon would have been entering the ocean from their natal streams to feed and grow.
The cold waters of the California Current flow southward from the northern Pacific along the West Coast and are associated with upwelling, an ocean condition caused by winds that bring nutrients to the ocean’s surface and is the main source of nourishment for the ocean’s food web. In 2005 a southward shift in the jet stream, delayed favorable winds and upwelling for the California Current, which normally begins in spring. The winds instead arrived in mid-July, causing high surface water temperatures and very low nutrient production within the nearshore marine ecosystem.
“We are not dismissing other potential causes for this year’s low salmon returns,” said Usha Varanasi, NOAA Fisheries Service Science Center Director for the Northwest Region. “But the widespread pattern of low returns along the West Coast for two species of salmon indicates an environmental anomaly occurred in the California Current in 2005.”
Data released Thursday by the Pacific Fisheries Management Council indicate the 2007 returns of fall Chinook salmon to the Sacramento River in California’s Central Valley were approximately 33 percent of what fishery biologists expected. Projections for 2008 are substantially lower than last year’s estimate. [http://www.pcouncil.org/newsreleases/Feb_2008_Sacramento_News_Release.pdf]
Coho salmon returning to spawning streams in California and Oregon are also considerably lower than predicted. A preliminary analysis found an average 27 percent of the parental stock returning in 12 streams monitored in California. Even though coho returns appear to improve along the coast from south to north, Oregon Coast coho salmon had less than 30 percent of their parental stock return.
Coho salmon are listed as either endangered or threatened under the Endangered Species Act in the Central/Northern California and Southern Oregon watersheds.
Jim Milbury | EurekAlert!
Upcycling of PET Bottles: New Ideas for Resource Cycles in Germany
25.06.2018 | Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF
Dry landscapes can increase disease transmission
20.06.2018 | Forschungsverbund Berlin e.V.
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences