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Bruce Finney, Professor

Email: - - - Phone: 208-282-4318

Gale Life Sciences Bldg., Room 236

Physical Science Bldg., Room 235


  • 1987, Ph.D., Oceanography, Oregon State University, Corvallis, OR
  • 1979, B.S. Geology, University of Minnesota, Minneapolis, MN


Bruce Finney is a professor in the Department of Biological Sciences, with a joint appointment in geosciences. Much of his research focuses on using lake and ocean sediment-based data to study past and future climate changes and its effects on wildlife, humans and fish. He is particularly well known for his research on the effects of climate change on Pacific salmon populations. More than 100 of Finney's publications have been featured in peer-reviewed journals, 40 of which have been published since his arrival at ISU in 2007. His publications have been cited more than 5,000 times in the peer-reviewed literature.

Finney's publications have been featured in several prominent journals, including Science, Nature and Proceedings of the National Academy of Sciences of the USA. Finney serves as assistant director for the Center of Archaeological Materials and Applied Spectroscopy (CAMAS), and is the director of the Stable Isotope Laboratory of the Interdisciplinary Laboratory of Elemental and Isotopic Analysis. Finney's research funding has totaled more than $7 million, much of which has come from a series of competitive grants from the National Science Foundation.


BIOL 4499/6608 Stable Isotopes in Environmental Science

Selected Publications

Ocean-atmosphere forcing of centennial hydroclimate variability in the Pacific Northwest. Steinman, B.A., Abbott, M.B., Mann, M.E., Ortiz, J.D., Feng, S., Pompeani, D.P., Stansell, N.D., Anderson, L., Finney, B.P., Bird, B.W. Geophysical Research Letters 41 (7):2553-2560; doi: 10.1002/2014GL059499, 2014.

Centennial-scale fluctuations and regional complexity characterize Pacific salmon population dynamics over the last five centuries. Rogers, L.A., Schindler, D.E., Lisi, P.J., Holtgrieve, G.W., Leavitt, P.R., Bunting, L., Finney, B.P., Selbie, D.T., Chen, G., Gregory-Eaves, I., Lisac, M.J. and Walsh, P.B. Proceedings of the National Academy of Sciences 110: 1750-1755, 2013.

A coherent signature of anthropogenic nitrogen deposition to remote watersheds of the Northern Hemisphere. Holtgrieve, G.W., Schindler, D.E., Hobbs, W.O., Leavitt, P.R., Ward, E.J., Bunting, L., Chen, G., Finney, B.P., Gregory-Eaves, I., Holmgren, S., Lisac, M.J., Lisi, P.J., Nydick. K., Rogers, L.A., Saros, J.E., Selbie, D.T., Shapley, M.D., Walsh, P.B., and Wolfe, A.P. Science 334: 1545-1548, 2011.

Fisheries productivity in the northeastern Pacific Ocean over the past 2,200 years. Finney, B.P., Gregory-Eaves, I., Douglas, M.S.V. and Smol, J.P. Nature 416: 729-733, 2002.

Impacts of Climatic Change and Fishing on Pacific Salmon Abundance Over the Past 300 Years. Finney, B.P., Gregory-Eaves, I., Sweetman, J., Douglas, M.S.V. and Smol, J. Science 290: 795-799, 2000.

Ongoing Research

Idaho State University research scientist Bruce Finney's ultimate goal is to help create accurate weather maps of the past for the American West that can be used to better predict future weather patterns.

It is a complicated endeavor, as the results of his recent research suggests, and a work in progress that is becoming more sophisticated as Finney examines the ancient sediment layers in lakes in the Pacific Northwest.

Finney, an ISU Biological and Geosciences professor, participated in a study "1,500 year quantitative reconstruction of winter precipitation in the Pacific Northwest"that was recently published in the Proceedingsof the National Academy of Sciences. That study has received wide publicity and attention because of its surprising results found by Finney and his colleagues at the University of Pittsburgh, Penn State and Ohio State. The researchers compared the data from the analysis of tree rings to that from lake sediments to see how they related. It turns out some periods of weather in the past were misidentified as being in drought.

"Water is a big deal in the West so we've been trying to get a longer-term perspective on how often and long droughts come and why they occur by analyzing lake sediments," Finney said. "This paper focuses on last 1,500 years. The lakes tell us more about what happened in the winter time, the trees tell us more about the summer."

Generally, in the short term the tree rings and sediment samples matched up, but in the long term they showed differences, showing that dry summers sometimes paired up with wet winters, or vice versa. This has caused scientists to reinterpret past weather patterns: some periods that were identified as drought based on tree ring data are now classified differently because lake sediment data showed wetter than average winters during the same period.

"It's not that one data set is correct and the other is wrong," Finney said. "The data is complementary because of the different seasons it corresponds with and that gives us a more detailed view of what happened in the past."

Drought is a common feature in the West's weather history, with several in the last 1,500 years lasting decades, according to Finney. One of those periods of generally droughty conditions in this region began about 500 years ago during the "Little Ice Age" ending about 1850.

"The climate has been all over the place in recent years," Finney said, "with wet years followed by dry years, but we're dryer than normal over the last dozen or so years."

The important part of this research is what it contributes to the big picture of the West's climate.

"We will now be able to compare these results to what we are determining happened in Idaho, Alaska and other places effected by weather patterns originating from the North Pacific Ocean over the same period," Finney said. "We're basically trying to put together maps to see what controlled wet and dry periods in the past to help know where the climate system is going in the future."

For his part in the study, Finney examined lake sediment core samples collected from Castor Lake, which is in northwestern Washington with funding from the National Science Foundation, and is currently involved in similar studies in Idaho, Alaska and other regions surrounding the North Pacific Ocean.

Researchers Make Corridor Discovery

A potential corridor along the coast of Alaska for humans to travel down to populate the New World was open and free of ice 1,500 to 2,000 years earlier than what was previous thought, according to a new study completed by Oregon State University and Idaho State University researchers.

"We dated core samples of lakes on Sanak Island, which would have been near the ocean shore at that time, and we determined the coast here was free of ice between 16,000 and 17,000 years ago, about 2,000 years earlier than what was previously thought," said Bruce Finney, ISU biological and geosciences professor.

This study has important implications for anthropologists and archeologists.

Many archeologists believe that the Americas were populated about 15,000 years ago or longer, but it was assumed that migrants from Asia couldn't come down the coast of the Alaska Peninsula prior to 13,000 years ago because it was covered by a massive sheet of ice, said Herbert Maschner, director of the Idaho State University Museum of Natural History.

"These new findings, however, indicate that this area was free of ice and fully vegetated as early as 16,000 to 17,000 years ago," Maschner said, "People could have migrated down the coast during this time, which correlates to the time of earlier archeological sites discovered in North and South America."

The ISU researchers pointed out that no evidence of human travel during this time frame has been found on Sanak Island, where the oldest known human activity is 6,000 to 7,000 years ago. However, the discovery that the ice left earlier than was previously thought - and when it was there was only half as thick as previously thought -- establishes that such migrations were possible.

Maschner, Finney and Mark Shapley were three of four ISU scientists who participated on the study "Early retreat of the Alaska Peninsula Glacier Complex and the implications for coastal migrations of First Americans" that was published in the journal "Quaternary Science Reviews" this month. That study has been publicized widely internationally in scientific and popular news outlets.

The study's lead author, Nicole Misarti, currently of the Oregon State University College of Earth, Ocean and Atmospheric Sciences, began the study during her Ph.D. research under Finney's supervision at the University of Alaska Fairbanks, and completed it while an ISU post-doctoral researcher working on the National Science Foundation Sanak Island Biocomplexity Project.

The Sanak Island is located about 40 miles from the coast of western Alaska Peninsula, about 700 miles southwest of Anchorage, Alaska.

Researchers Published in Science

Two Idaho State University scientists - biological and geosciences professor Bruce Finney and geosciences post-doctoral researcher Mark Shapley - are among a team of 19 researchers who have documented the signature of increased human nitrogen emissions across the Northern Hemisphere in study that has been published in the prestigious journal Science.

Plenty has been written about the increase of carbon released in the environment by humans, but this is a major study documenting the release of nitrogen, which also has the potential for dramatic environmental effects, into remote watersheds in Idaho, the western United States, Canada, Alaska, Greenland and Norway.

The lead author on the study "A Coherent Signature of Anthropogenic Nitrogen Deposition to Watersheds of the Northern Hemisphere" was Gordon Holtgrieve, from the University of Washington School of Aquatic and Fishery Sciences. He worked with colleagues from around the globe on the study published Dec. 16.

"Unlike carbon, nitrogen is generally distributed more closely to its human-caused sources, but we found evidence of its distribution in places far away from its sources," Finney said. "The release of nitrogen from human sources really starts to pick up about 100 years ago (this paper analyzes nitrogen sources going back 400 years) and it has increased exponentially to the present."

Finney and Shapley have been taking sediment core samples from remotes lakes in the Pacific Northwest and Alaska. They extract sediment samples from lakebed mud, and — similar to analyzing tree rings — interpret layers of sediment using a sophisticated instrument called a mass spectrometer.

The researchers measured recent changes in the ratio of nitrogen isotopes, which are distinct forms of the element, which identifies input from human activities.

"Nitrogen coming from humans has a signature that is different from nitrogen from other sources," notes Finney.

The new study appearing in Science is an expansion of an earlier study of lakes in the Pacific Northwest and Alaska that was co-led by Finney and three other principal investigators who are authors on this study.

"This is probably the first good evidence that watersheds in these remote areas of the world are having their nitrogen budgets changed in ways we can detect over the last century," Shapley said. "Changes in nitrogen levels really tend to have widespread and significant changes on the ecosystems supported by those lakes.

"Organisms in these lakes," continued Shapley, "are sensitive to nitrogen in those watersheds. Human loading of nitrogen in the atmosphere is having a hemispheric, and possibly global impact. It's possible that widespread changes in the ecosystems may not be far behind."

Humans release nitrogen into the environment through a wide variety of means, including burning fossil-based and other fuels and applying fertilizers.

"The studies on nitrogen have implications for carbon cycles in the environment as well," Finney said. "People studying the global carbon cycle know it does not work separately from nitrogen. You have to think of the cycles of both nitrogen and carbon to understand how they will change in the future."

Other co-authors are Daniel Schindler, Peter Lisi and Lauren Rogers with the University of Washington, Alexander Wolfe with the University of Alberta, William Hobbs with Science Museum of Minnesota, Eric Ward with National Marine Fisheries Service, Lynda Bunting and Peter Leavitt with University of Regina; Guangjie Chen with McGill University and Yunnan Normal University, Irene Gregory-Eaves with McGill University, Sofia Holmgren with Lund University, Mark Lisac and Patrick Walsh with U.S. Fish and Wildlife Service, Koren Nydick with Mountain Studies Institute, Colorado, Jasmine Saros with University of Maine, and Daniel Selbie with Fisheries and Oceans Canada.

Funding came from the Gordon and Betty Moore Foundation, U.S. Fish and Wildlife Service, Alberta Water Research Institute, Natural Sciences and Engineering Research Council of Canada, the National Science Foundation, and Canada Foundation for Innovation.

Science is produced by the American Association for the Advancement of Science (AAAS). Founded in 1848, AAAS serves some 262 affiliated societies and academies of science, serving 10 million individuals. Science has the largest paid circulation of any peer-reviewed general science journal in the world, with an estimated total readership of one million. The website for Science is

ISU researcher uncovers traces of ancient Idaho sockeye runs

Posted August 11, 2008

While the public and biologists are enjoying the rare opportunity to view sockeye salmon in Idaho’s upper Salmon River this year, an Idaho State University research professor has taken looks at Gem State sockeye salmon runs going back thousands of years.

Today’s fisheries managers are thrilled by the return of hundreds of fish to the Sawtooth Valley, but historically the run consisted of tens of thousands of sockeye, according to Idaho State University research professor Bruce Finney, Ph.D.

Researchers on Redfish Lake in process of taking sample. Photo by Jason Addison. Photos provided by Mark Shapley.

Researchers on Redfish Lake in process of taking sample. Photo by Jason Addison. Photos provided by Mark Shapley.

As of early August, more than 850 rare sockeye salmon had passed over the Lower Granite Dam, the last barrier on the Snake River that salmon must pass before entering Idaho. Fisheries biologists predict as many as 700 fish could return to the Sawtooth Fish Hatchery near Redfish Lake, which is near the town of Stanley. To get to this hatchery the fish travel nearly 900 miles.

Some years there are only single-digit or zero returns of the sockeye. The largest number to return to central Idaho in a year since 1985, when biologists starting counting the runs, was 257 sockeye in 2000. Since 1985, just 352 wild and hatchery-origin sockeye have returned to the Redfish Lake area. Redfish Lake is named for sockeye, which turn a reddish color when they spawn.

While this relatively strong run is encouraging to those who want to save the fish, this year’s run is a small fraction of the size of sockeye runs that historically returned to spawn in the lakes of the upper Sawtooth Valley, including Redfish, Petit and Alturas Lakes. According to Finney from 25,000 to 40,000 sockeye historically spawned annually in Redfish Lake alone prior to the 1900s.

Scientists using the equipment on the deck of one of the drilling boats. Photo by Dave Gilbert.

Scientists using the equipment on the deck of one of the drilling boats. Photo by Dave Gilbert.

Finney bases this calculation on work he has done examining the sediment cores from lakes using a machine called a mass spectrometer. Mass spectrometers are instruments that can measure the masses and relative concentrations of atoms and molecules in chemical compounds and other samples. Spectrometers accurately measure the different types of isotopes of the same element such as carbon or nitrogen in biological or geological samples.

Finney has developed a technique using mass spectrometers to reconstruct the salmon runs in the past. Salmon have a signature type of nitrogen, recorded by nitrogen isotopes, which scientists can use to positively identify as originating from the salmon.  When the salmon die and they decompose they release nitrogen, which is in turn taken in by algae that end up in lake sediments. High salmon runs correspond to higher concentrations of these nitrogen deposits; lower concentrations of nitrogen in deposits represent smaller runs. The sediments on lake bottoms can be dated using radiocarbon dating, an accurate method for dating materials and by identifying ash layers from known volcanic events.

So far, Finney and his colleagues have studied core samples from some of the larger lakes in the upper Sawtooth Valley, including Redfish Lake, dating back about 2,000 years.

Drilling rig on Petit Lake. Photo taken by Jason Addison.

Drilling rig on Petit Lake. Photo taken by Jason Addison.

Although there were fluctuations, sockeye runs until about a century ago were consistently high, but populations crashed as Old World settlers developed the region. Finney’s mass spectrometer measurements confirm anecdotal and eyewitness accounts of what led to the precipitous demise in the Idaho upper Salmon River sockeye population: the creation in 1910 of the Sunbeam Dam, located about 15 miles downstream of Stanley.

“The most dramatic decline in salmon runs occurred when the Sunbeam Dam was built,” Finney said. “Its creation just overwhelms any naturally occurring fluctuations that occurred previously.”

The creation of the Sunbeam Dam shows how Finney’s technique can be used to help confirm other data about Pacific salmon runs that has been collected in the last 100 to 150 years. However, his data can also be used to help create a picture of what runs were like prior to modernization in the New World, when commercial fishing increased, rivers were dammed and there were other numerous large-scale factors that potentially altered salmon runs.

The information Finney collects about pre-industrial age salmon runs may be of even more use. Based on data Finney collected while doing a similar study in Alaska, fishery managers in one area changed their management goals based on historical salmon runs from prior to when fishery records were kept. This is one example of the large number of ways that Finney’s research is applicable to current management.

In completing his studies on various lakes from Alaska to the Pacific Northwest, analyzing runs that have occurred as far back as 10,000 years, Finney has confirmed that salmon population fluctuations occurred regularly in response to naturally occurring climatic events. This is also useful information because it can give managers a framework about what happens to fish runs in a particular area in response to a warming or cooling trend. That information could potentially be used by current fisheries managers to develop harvest guidelines for particular fisheries.

Finney is involved in a major research project with researchers from three other universities to synthesize all the results from lake core sample studies that have been obtain in Alaska, British Columbia, Yukon Territories and in the Pacific Northwest. The results of that study could help researchers build a sweeping view of salmon run patterns occurring over a larger time and geographical scale.