"Our collaborative UC Davis and University of Nevada, Reno, science team found up to 3,000 Asian clams per square meter at locations between Zephyr Point and Elk Point in the southeastern portion of the lake," said John Reuter, associate director of the UC Davis Tahoe Environmental Research Center.
"Those are high numbers, especially when compared to the few isolated, dead shells we found back in 2002 when the Asian clam was first reported. We already see associated environmental effects from the clams today, and we are concerned that they might spread.”
Issued annually since 2007, the "Tahoe: State of the Lake Report" is intended to give the public a better understanding of the changes occurring in Lake Tahoe on a year-to-year basis and to place current conditions within a historical perspective. It summarizes tens of thousands of scientific observations of lake weather, water conditions and aquatic life made since 1900. It is compiled by the research scientists of the UC Davis Tahoe Environmental Research Center.
The dime-sized Asian clam (Corbicula fluminea) that is the researchers’ top concern this year probably has been in the lake for only 10 years, but it is already replacing native pea clams in lake sediments. In the areas where they are most numerous, Asian clams comprise almost half of the benthic, or sediment-dwelling, organisms, the report says.
What's more, in the beds of Asian clams, a green filamentous alga, Zygnema, is thriving. The report says the algae probably are being nourished by the high concentrations of nutrients excreted by the clams. Dead Zygnema clumps become a nuisance when they wash onto beaches and decompose. “This moves Lake Tahoe further away from its desired pristine condition,” Reuter said.
Another worry: UC Davis and UNR researchers say accumulations of Asian clams might foster the invasion of two other damaging species: quagga and zebra mussels, which radically alter ecosystems by consuming enormous amounts of the tiny algae that are the base of lake food chains and outcompeting the native bottom-dwelling species. The mussels are also feared for their ability to encrust piers and boat hulls, and have already caused millions of dollars in damage in the Great Lakes by blocking intake pipes at water and power plants.
Zebra and quagga mussels are spreading west by hitchhiking on boat hulls, and a comprehensive program of public education and boat inspections has been established by resource managers to try to keep them out of Lake Tahoe. While Asian clams are not expected to become the colonizing monster that quagga and zebra mussels are, they may make lake waters more hospitable to the problem mussels by concentrating calcium, an essential nutrient.
In addition to the Asian clam concerns, many other trends and observations are described in the 64-page State of the Lake Report. They include:The lake’s clarity was unchanged from the previous year: The Secchi depth was 69.6 feet.
The "Tahoe: State of the Lake Report 2009" is free and available online at http://terc.ucdavis.edu.
About the Tahoe Environmental Research Center
The Tahoe Environmental Research Center (TERC) is dedicated to research, education and public outreach on lakes and their surrounding watersheds and airsheds. Lake ecosystems include the physical, biogeochemical and human environments, and the interactions among them. The center is committed to providing objective scientific information for restoration and sustainable use of the Lake Tahoe Basin.
About UC Davis
For 100 years, UC Davis has engaged in teaching, research and public service that matter to California and transform the world. Located close to the state capital, UC Davis has 31,000 students, an annual research budget that exceeds $500 million, a comprehensive health system and 13 specialized research centers. The university offers interdisciplinary graduate study and more than 100 undergraduate majors in four colleges — Agricultural and Environmental Sciences, Biological Sciences, Engineering, and Letters and Science — and advanced degrees from six professional schools — Education, Law, Management, Medicine, Veterinary Medicine and the Betty Irene Moore School of Nursing.
John Reuter | EurekAlert!
Further reports about: > Corbicula fluminea > Environmental Research > Environmental Research Center > Invasion > Lake Baikal > Medicine > Science TV > Tahoe > Zebra mussels > Zygnema > bottom-dwelling species > deep water > environmental risk > food chain > green filamentous alga > hitchhiking on boat hulls > quagga mussels
Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide
Malaysia's unique freshwater mussels in danger
27.09.2016 | The University of Nottingham Malaysia Campus
Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.
This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
27.10.2016 | Materials Sciences
27.10.2016 | Physics and Astronomy
27.10.2016 | Life Sciences