Elwha River in Olympic National Park in Northwest Washington. Courtesy: John McMillan, NOAA

A new analysis of streams in the western United States has found that despite a general increase in air temperatures over the past several decades, western streams are not necessarily warming at the same rate. Several factors may influence the discrepancy, including snowmelt, interaction with groundwater, water flow and discharge rates, solar radiation, wind, and humidity. But even after factoring out those elements, the scientists detected cooler-than-expected maximum, mean, and minimum stream temperatures. Looking at streams individually, they found that some seemed to be getting warmer, some cooler, and others showed little change at all.

Results of the research, which was supported by the U.S. Geological Survey, the U.S. Forest Service, and Oregon State University, are published in Geophysical Research Letters, a journal of the American Geophysical Union.

Cold, clean water is one of the most important ecosystem services in the western United States. Many species of economically and culturally important salmon, trout, and other species depend on these cold waters to thrive and survive, so naturally, the potential loss of cold water in the face of climate change is a concern.

These findings show that changes in stream temperatures will not simply parallel changes in warming air temperatures, as commonly assumed or

Cutthroat trout in the Middle Fork Salmon River, Idaho. Courtesy: Steve Jacobs

projected. They point to the likely importance of local factors, such as land form, land cover, and geology, in influencing climate sensitivity of stream temperatures. A second key finding is that the vast majority of streamgages in the region either lack long-term data or are too strongly influenced by local human activities to provide a clear evaluation of climate effects.

For this study, researchers used long-term records from USGS and U.S. Forest Service gaging stations. Of the more than 600 stations evaluated from California, Nevada, Oregon, Idaho, Washington, and Alaska, less than 20 were suitable for analyzing climate effects. This set included streams with minimal human influences and sufficiently long-term records of temperatures for an evaluation of trends.

Rogue River Canyon in southwestern Oregon. Courtesy, Ruth Jacobs, USGS

These results highlight the fact that stream temperature is one of the most important, yet least understood aspects of climate change. The researchers caution that the findings do not mean that climate change will not affect stream temperature, which is a fundamental driver of ecosystem processes in streams. However, the relationship between air temperatures and stream temperatures may be more complex than previously realized and require additional monitoring.

The paper, The paradox of cooling streams in a warming world: regional climate trends do not parallel variable local trends in stream temperature in the Pacific continental United States, was authored by Ivan Arismendi, Oregon State University; Sherri Johnson, U.S. Forest Service; Jason Dunham, USGS; Roy Haggerty, Oregon State University; and David Hockman-Wert, USGS.

Additional Links:

Reconstructing Thermal Regimes in Streams from Sclerochronology of Freshwater Mussels (link to a paper, a USGS podcast, and an Oregon Field Guide television episode about the research)

http://fresc.usgs.gov/research/StudyDetail.asp?Study_ID=558

Climate Impact on Streamflows, Thermal Regimes, and the Changing Distribution of Trout in the Great Basin

http://fresc.usgs.gov/research/StudyDetail.asp?Study_ID=734

USGS Forest and Rangeland Ecosystem Science Center Aquatic Ecology Laboratory

http://fresc.usgs.gov/AquaticEcologyLaboratory/

August 31, 2011 - USGS Director Dr. Marcia McNutt formally dedicating the Research Vessel Muskie to the USGS during a recent celebration at the Great Lakes Shipyard, marking the completion of the $8.2 million project.

Construction of the R/V Muskie (left) and the R/V Kaho (below) is now complete and the vessels are equipped to assume research duties in 2012. The R/V Muskie will be christened and commissioned on Wednesday, October 19 at the Sandusky Yacht Club in Ohio.  The R/V Kaho will be christened and commissioned in the spring of 2012 at the USGS Lake Ontario Biological Station in Oswego, New York.

August 31, 2011 - The Honorable Anne Castle (Assistant Secretary for Water and Science, U.S. Department of the Interior) formally dedicating the Research Vessel Kaho to the USGS during a recent celebration the Great Lakes Shipyard, marking the completion of the $8.2 million project.

Deputy Director Dr. Suzette Kimball will christen the R/V Muskie by breaking a bottle of champagne across its bow and formally naming the vessel.  Ms. Pamela Dei, a USGS mechanical engineer who’s played a major role in the contracting and construction process for the vessels, will christen the R/V Kaho.

Twin Sisters

The two ships are sister ships, and will continue long-term research programs on populations of predator and prey fishes in lakes Erie and Ontario. The Muskie will be stationed in Lake Erie, and the Kaho will be stationed in Lake Ontario. Both ships are 70.8 ft. in length and have a draft (displacement) of five feet or less. This puts them at the smaller end of the GLSC fleet, which boasts two ships with greater than 100 ft. in length, and one with 75 ft. in length. However, the R/V Kaho and R/V Muskie, with their much shallower draft, are able to do research closer to shore, making them ideal for the smaller lakes.

“The R/V Muskie and the R/V Kaho will provide safe and reliable platforms for scientists, and are equipped with state-of-the-art scientific instrumentation to improve our understanding of deep-water ecosystems and fishes in lakes Erie and Ontario,” said Russell Strach, director of the GLSC.

Strach noted that the new vessels will replace the oldest vessels in the fleet – those on lakes Erie and Ontario – and will have increased fuel efficiency, lower maintenance costs, and greater research capacities, especially because the boats they are replacing functioned on 1950s and 60s technologies.

Additional improvements in the two ships, such as increased bunk space and shower facilities, allow them to spend more time at sea, enhancing the research capabilities of the GLSC.

Critical Research

USGS researchers deploy a beam trawl from the R/V Kiyi

Researchers at the GLSC are eager to use the large vessels to better assess and explore the health and population status of Great Lakes deep-water ecosystems.  USGS science is critical for federal, state, and tribal resource managers to make decisions that effectively protect the area’s $7 billion annual commercial and sport fisheries.

The GLSC is the only federal center that has a large scientific research vessel stationed on each of the Great Lakes capable of working for extended periods of time in offshore, deep-water areas.  The research programs facilitated by the GLSC’s fleet, are critical to managing and conserving Great Lakes resources, and are used by Great Lakes state,  provincial, and tribal management agencies across the basin.

USGS GLSC researchers use their ships to study populations of key predator and preyfish to inform the decisions of resource managers.

The USGS awarded an $8.2 million contract to the Great Lakes Towing Company (Cleveland, Ohio) in June 2010 for the construction of the two large vessels.  Funding for the contract came from American Recovery and Reinvestment Act.

The GLSC’s mission is to meet the nation’s need for scientific information for restoring, enhancing, managing, and protecting living resources and their habitats in the Great Lakes basin ecosystem.

Don’t forget, the R/V Muskie and R/V Kaho are just two of the GLSC’s fleet!  Meet the rest of them here!

Contact: Holly Patrick

Adult Lionfish

Non-native lionfish are rapidly spreading along the U.S. Eastern seaboard, Gulf of Mexico, and Caribbean and have been preying on and competing with a wide range of native species.  

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