Water defines life in Wisconsin. Our landscape, history, cultures, communities, ecosystems, and economy are fundamentally shaped by water. With the Great Lakes on Wisconsin’s eastern and northern borders, the Mississippi River to the west, and a vast network of surface waters, water may be our most precious resource. Indeed, opinion poll responses in the wake of the Wisconsin Academy’s landmark three-year study of Wisconsin’s waters, Waters of Wisconsin: The Future of Our Aquatic Ecosystems and Resources, tell us that “Wisconsinites don’t just value their waters—they love them.”
Limnology, the study of inland waters, is an academic discipline of great interest to the citizens of Wisconsin. University of Wisconsin–Madison limnologists have been studying the waters of Wisconsin since 1895 with the goal of finding solutions to the vexing and myriad challenges our waters continually face. Examining the causal relationships involved in nutrient pollution and lake food webs, studying the impact of dams (and their removal) on rivers, monitoring the health of the Great Lakes, and evaluating the impact of climate change on our waters are all in a day’s work for the scientists at the university’s Center for Limnology.
Water is the essential condition for life on earth—one that has no substitute. Yet, freshwaters are the most altered ecosystems on the planet. As changes in human activity affect lakes and rivers—not only in Wisconsin but also across the world—scientific research from the Center for Limnology and other academic centers becomes ever more central to our ability to responsibly manage water resources.
Many Wisconsin Academy members will remember the Wisconsin Academy’s Waters of Wisconsin (WOW) project, which produced in 2003 a series of recommendations on the best policies and management of our waters for the beginning of the 21st century. Faculty from the Center helped lead this project and generate knowledge used in this landmark study.
In 2013 and for the next few years, some of the original WOW participants from the Center—along with many more from across the state of Wisconsin—will help the Wisconsin Academy lead a renewed WOW initiative that will explore new and more complex threats to water which require a fresh examination of the way forward. The renewed WOW initiative will foster nonpartisan, science-based strategies and solutions to safeguard Wisconsin’s freshwater ecosystems and water supply for generations to come.
The Center for Limnology has had a long and fruitful relationship with the Wisconsin Academy. Breaking New Waters: A Century of Limnology at the University of Wisconsin, is a detailed history of the first century (1875–1978) of the Center’s growth and development. Written by Annamarie Beckel and published in Transactions (1987), the Wisconsin Academy’s scholarly journal, this comprehensive review of the work of Edward A. Birge, Chancey Juday, and Arthur D. Hasler clearly established these scholars as foundational to the Center.
The purpose of this article is to fortify the pillars of this foundation by tracing the development of the Center in the first three decades of its second century: 1978–2009. What follows is an overview of five of the most important events in this period under the leadership first of Professor John Magnuson (1982–2000) and, second, of Professor Jim Kitchell (2001–2009).
>>>Creation of the Center for Limnology<<<
Classes on the study of inland waters had been part of the UW–Madison Department of Zoology curriculum since 1875 and were largely conducted in the Laboratory of Limnology on the shore of Lake Mendota near Memorial Union. When Arthur D. Hasler came onboard, he placed a new emphasis on controlled experiments in the field. An intellectual giant in the field, Hasler for decades guided limnology-related work at UW–Madison. When he retired in 1978, his young associate, John Magnuson, took over leadership of studies in limnology.
At that time, if the limnology faculty—which consisted of Magnuson and Jim Kitchell—wanted to grow and develop the program, they had to compete with the whole Zoology Department for resources. Limnology was just one of the many interests of the Department of Zoology; as such the field often came up short on funding.
Yet there was growing recognition that Wisconsin’s lakes were an important economic resource, deserving of more study. After a considerable amount of conversation and negotiation, Department of Zoology Chair Seymour Abrahamson, Dean Robert Bock of the Graduate School, and Dean David Cronon of the College of Letters and Science all agreed with Magnuson that limnological studies should be formally incorporated as an independent entity known as the Center for Limnology within the College of Letters and Science. Magnuson became the Center’s first director until his retirement in 2000 when he turned the reins of leadership over to Kitchell.
What was particularly important about the establishment of the Center in 1982 was the freedom of operation that it obtained. While the Center maintained strong formal and informal ties to the Department of Zoology, its subsequent growth into one of the most significant limnological research sites in the world owes much to the freedom to appeal directly to the university for necessary support through, for example, research grants from the Graduate School, Wisconsin Alumni Research Foundation, and Sea Grant Institute.
Reflecting on the development of the Center in a recent interview, Magnuson observed that the feeling during those nascent years was that of a “commons.” Collaboration and collegiality governed all aspects of the work at the Center for Limnology, both programmatic and administrative.
This approach to intellectual activity was initiated by Hasler and has been successfully maintained by his successors ever since. For instance, the Center operates on a democratic basis using a system of committees: faculty, staff, and students all share power. Faculty at the Center interact continuously and regularly review each other’s work in the search for new knowledge and opportunities for collaboration. New faculty members are expected to pursue their own research interests but with a consistent commitment to determining the best way to apply the new knowledge and get it out into the world. A core principle of the Center, the importance of this collaborative approach cannot be overstated.
>>>The Long Term Ecology Research Project<<<
While the Center for Limnology was striving for recognition as a distinct research entity, an opportunity presented itself through the National Science Foundation (NSF) to become a much bigger player in the field.
Magnuson, who had been invited to join the NSF in 1975 as Director of the Ecology Program, was part of an effort organized by the NSF to create a Long Term Ecology Research (LTER) program, which would look in detail at a variety of ecosystems across the U.S.—from rainforests on the Northwest coast to the tidelands of Georgia—and follow them over decades.
The need for an LTER program arose from discussions at the time about how long-term ecological phenomena in lakes—nutrient and hydrologic cycles, for instance—cannot be adequately understood within the three-year time frame of traditional NSF grants. The grant cycle was simply too short.
Among the eighteen systems the NSF initially targeted were north temperate lakes, the kind found in Northern Wisconsin. When the NSF called for proposals, the Magnuson sought out UW–Madison colleagues who might be interested in collaborating on a LTER project here in Wisconsin. One historical strength of UW–Madison is its extraordinary commitment to create and execute interdisciplinary research; the Center made great use of the university’s commitment in formulating their Long Term Ecology Research proposal to the NSF.
While the Center for Limnology led the proposal effort, all of the faculty who would be involved in the project made major contributions. These faculty, who already had many years of working together under the auspices of the Oceanography and Limnology Graduate Program, included Carl Bowser of geochemistry and hydrology, Mary Anderson of hydrology, Thomas Brock of microbiology and limnology, and Robert Ragotzkie of atmospheric science and physical oceanography. This talented group put together a proposal that addressed large, over-arching concepts and stressed the need to understand lakes’ relationships with their surrounding landscapes and how they are linked through surface and underground hydrologic flow systems.
The end result was that the Center received one of the five NSF grants awarded out of a total of thirty submissions for the North Temperate Lakes program. Magnuson went on to direct this project on lake ecology until he stepped down and became an Emeritus Professor in 2000.
The Center for Limnology’s Trout Lake Station in northern Wisconsin, which has been an important site for limnological studies since 1925 (for more information on the station, please see the sidebar beginning on the opposite page), was chosen as a research hub for the Center’s LTER project.
In particular, a cluster of seven lakes located near the station are ideal for studying long-term lake changes and dynamics in a landscape context. Though situated fairly close to one another, the lakes differ greatly in fundamental properties like acidity, vegetation, and fish population. These differences can be used to successfully isolate important chemical, physical, and biological control factors for lake processes and thereby increase the understanding of how lakes operate and change over time, how internal versus external factors influence changes and year-to-year dynamics, and how lakes are influenced by major disturbances.
The Center’s North Temperate Lakes Long Term Ecological Research Project has been renewed by NSF every six years since it was first awarded in 1981; other grants and researchers have built on the LTER’s science platform with its strong and continuing database. The NSF’s long-term support for the Center’s project provided a foundation for the continued excellence of limnology research in Wisconsin.
>>>Trophic Cascade Theory<<<
Around the same time the LTER project was coming together in the 1980s, Jim Kitchell initiated another new area of research focused on re-evaluating how lake ecosystems worked. Working with friend and colleague Stephen Carpenter, a professor of biology at Notre Dame University, the two began to question the established concept of how lakes create food for fish.
The thinking of the time was reflected in a bottom-to-top food chain: nutrients feed algae, which creates food for zooplankton, which become food for fish.
However, this simple transfer of food up the chain could not explain variability in the amounts and types of algae and zooplankton among neighboring Wisconsin lakes, or among other lakes of the world. Kitchell and Carpenter postulated that perhaps there was something else going on besides nutrient input that regulated algae production, a kind of “feedback” mechanism.
That mechanism proved to be the predation pressure exerted by fish, which changes the zooplankton population and thereby changes the amount of algae. When the population of large predator fish dwindles, the number of small fish that feed on zooplankton increases. This in turn reduces the zooplankton population, allowing algae to thrive. By transplanting top predators like walleye and pike from one lake to another, Carpenter and Kitchell found they could transform the food chains of both lakes and dramatically change the levels of algae.
The success of the experiment prompted the Wisconsin Department of Natural Resources (DNR) and area fishing clubs to undertake a major fish-stocking program to improve the water quality of Lake Mendota. This biomanipulation project of 1987–1989 was supported by new fishery regulations that created a “trophy” fishery to protect and increase numbers of top predator fish. At the same time, DNR Director of Fisheries James Addis obtained funds for the massive stocking of walleye into Lake Mendota. Plankton and fish communities responded. Both fisheries and water quality improved. The effort was received with interest by fishery managers and scientists around the world, and led to the 1992 book edited by Kitchell, Food Web Management: A Case Study of Lake Mendota.
This revision of the bottom-to-top food chain theory, called trophic cascade theory, also enabled Kitchell to explain the complex changes in Lake Michigan fisheries from the 1940s to about 2000. The ancestral top predator, the lake trout, disappeared by mid-century due to overfishing and the invasion of parasitic sea lamprey. Alewife, a small fish that had also invaded Lake Michigan, exploded in population and began feeding heavily on zooplankton. By the 1960s, mass dieoffs of alewife due to overpopulation were fouling Lake Michigan beaches.
Drawing on the old, bottom-to-top food chain thinking, Pacific salmon species were stocked in the lake to control the alewife and create a sport fishery. But Kitchell had predicted that salmon would overshoot their food base, and his forecast proved correct. By the 1990s, salmon stocking had reached unsustainable levels as the alewife population declined. (In recent years, fisheries managers have adjusted salmon stocking levels toward a better balance with their prey and the rest of food chain.)
>>>Increasing the Faculty<<<
When Hasler retired in 1978, it was immediately clear to both Magnuson and Kitchell—who were the only limnological faculty at the time—that more faculty were needed if there was to be a successful limnology program at UW–Madison. With the 1982 formation of the Center for Limnology, they could begin looking for private resources to support additional faculty.
Reed Coleman, a prominent Madison businessman and president of the philanthropic Norman Bassett Foundation, became acquainted with Magnuson through their work with the Sand County Foundation, which seeks to honor and perpetuate the work of Aldo Leopold. In the mid-1980s Coleman, who has a degree in ecological science, approached Magnuson with an offer to have the Bassett Foundation partially fund a new faculty position in limnology, provided the university agreed to pick up full funding five years hence. Magnuson secured the additional required financial support by working with both the College of Letters and Science and the university’s fund-raising arm, the University of Wisconsin Foundation.
As has been noted earlier, Kitchell had developed a good relationship with Notre Dame’s Stephen Carpenter, who had received his PhD in botany, oceanography, and limnology from the UW–Madison in 1979. Carpenter was interested in working at the Center and had a one-year sabbatical there in 1987–1988. Thanks to Bassett Foundation support and his successful application for a faculty position in the Zoology Department, Carpenter joined the Center in 1989.
Like Magnuson and Kitchell, Carpenter has distinguished himself with his work in the field. Besides his expertise in nutrient cycling and physical and chemical limnology, Carpenter brought a conceptual interest in ecosystem science and large-scale ecosystem modeling. Today Carpenter is director of the Center for Limnology.
A decade after Carpenter joined the center, it became clear to the limnological leadership that an effort should be made to add a fourth faculty member, one with an interest in stream ecology. The Center submitted a proposal for an NSF training grant in collaboration with the University of Washington to integrate lake and stream ecology in graduate training. While funding of that NSF proposal generated momentum for the next faculty hire, additional resources were required.
In response to a request from Magnuson, Coleman again applied funds from the Bassett Foundation to partially support a new faculty member in the field of stream ecology. UW–Madison and the Foundation followed suit. Carpenter, who was aware of the work of Emily Stanley at Oklahoma State University, encouraged Kitchell to attend one of Stanley’s research presentations at a national meeting. Shortly after, Stanley was hired through Zoology as the Center’s point person for a new research emphasis on stream and river ecosystems.
In an August 22, 2012, letter to the author, Coleman said the following about his involvement with the Center: “I knew the Department of Limnology and its prominence all the way back to the time of Hasler. … It is obvious [to me] that [Magnuson and I] devised something that worked well. … The record compiled by Carpenter and Stanley stands tribute to the fact that it was a pretty good idea.”
When first Magnuson, and then Kitchell, announced their retirements, the Center, again through Zoology, added new younger faculty: Jake Vander Zanden and Peter McIntyre, both of whom have an admirable breadth of knowledge and commitment to research. Vander Zanden has special interest in invasive species and food webs, while McIntyre studies the organism-ecosystem interface in rivers and lakes around the world. The Center also promoted Paul Hanson, who had secured his PhD from UW–Madison in 2003, to apply computer technology and software to ecosystems sciences.
>>>The Education and Training of Grad Students<<<
Beginning with Hasler and continuing today, the Center has emphasized the education and training of graduate students. Many faculty suggest that the most important product of the Center may not be scientific papers but the people who graduate; these bright young scholars move out into the worlds of academe or program management and policy—and they make a real difference. Many of the leading limnologists at American universities today are graduates of Wisconsin’s Center for Limnology.
Because the Center for Limnology is so highly regarded in the field, admission to the graduate program is keenly competitive and rigorous. Applicants meet with several faculty prior to admission, and extreme care goes into selecting whom to accept. Among the qualities considered is commitment to collaboration and collegiality; much attention is paid to finding those intellectually qualified applicants who also share this approach to their work.
Because of the universal high quality of accepted graduate students, faculty are able to greatly expand the number of areas they can investigate by engaging these talented students in new research projects. In many ways, past graduate students—now on their own—represent the legacy of their professors and their capacity to influence another generation of advocates for Wisconsin’s—and the world’s—inland waters.