Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Foothill yellow-legged frog provides insight on river management

River flow fluctuations downstream of dams are often out of sync with natural flow patterns and can have significant negative effects on aquatic species, such as native frogs, according to a team of scientists from the USDA Forest Service's Pacific Southwest Research Station, the University of California, Davis and the University of California, Berkeley.

The team examined how altered water flows caused by hydroelectric dams impact the life cycle of the foothill yellow-legged frog (Rana boylii). The frog, which lives in foothill regions from southern California to southern Oregon, completes its life cycle exclusively in riverine environments.

The species is well-adapted to predictable flow patterns that are high during the spring run-off period and low during the summer. Changes to these patterns affect the survival of eggs and tadpoles and consequently are likely to be a primary factor in limiting populations of this declining species, scientists say.

Findings from three recent research projects are published in Copeia, River Research and Applications, and Conservation Genetics. These studies revealed that R. boylii tadpoles are not strong swimmers and do not survive the high flow events that can occur during the summer months in many dammed rivers, leading to local population declines. The team tested a habitat modeling tool that is commonly used for fish, with eggs and tadpole data from R. boylii, and found that it could provide reliable predictions of habitat changes under different flow scenarios. Genetic research conducted by the team identified several isolated and unique populations at the extremes of the geographic range and also demonstrated the important role of river basins in defining relationships among populations. The combined results of this work can guide conservation planning for the species.

Managing water discharge from hydroelectric dams to mirror the environment's natural flow is ideal, but this approach may not meet the needs of human consumption and energy demands.

"To conserve riverine species, one solution may be to restore some of the key characteristics of natural flow patterns, especially the timing of high and low flow periods," says Amy Lind, wildlife biologist at the Pacific Southwest Research Station in Davis, Calif., and co-author of three recent papers on R. boylii ecology and genetics.

For more information about this research, go to a recently developed website focused on this species at:

The team's three research papers can be found at:

The Pacific Southwest Research is headquartered in Albany, Calif. The station develops and communicates science needed to sustain forest ecosystems and other benefits to society. It has laboratories and research centers in California, Hawaii and the United States-affiliated Pacific Islands. For more information, visit

Sherri Eng | EurekAlert!
Further information:

More articles from Life Sciences:

nachricht Don't Give the Slightest Chance to Toxic Elements in Medicinal Products
23.03.2018 | Physikalisch-Technische Bundesanstalt (PTB)

nachricht North and South Cooperation to Combat Tuberculosis
22.03.2018 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Space observation with radar to secure Germany's space infrastructure

Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.

The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...

Im Focus: Researchers Discover New Anti-Cancer Protein

An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.

The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

New solar solutions for sustainable buildings and cities

23.03.2018 | Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

Latest News

For graphite pellets, just add elbow grease

23.03.2018 | Materials Sciences

Unique communication strategy discovered in stem cell pathway controlling plant growth

23.03.2018 | Agricultural and Forestry Science

Sharpening the X-ray view of the nanocosm

23.03.2018 | Physics and Astronomy

Science & Research
Overview of more VideoLinks >>>