[Randy Fuller]

Randall Fuller (Professor)

Department of Biology, Colgate University

Phone: 315.228.7393 Fax: 315.228.7997

E-Mail: RFuller@mail.colgate.edu

Research Interests: Trophic relationships and energy flow in stream ecosystems; predator-prey interactions; algal-bacterial interactions.  [Details]

Teaching Interests: Introductory biology, ecology, limnology and environmental studies courses. [Details]

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Randall Fuller

Research Interests:

        My research interests are primarily in stream ecology and have spanned all trophic levels from how light influences algae and thus bacteria to how algal abundance affects macroinvertebrates in forested versus agricultural streams. In addition, I have examined the degree of overlap in diets of fish versus invertebrate predators that share prey pools in specific reaches of streams. Students are an integral part of my research and I rely heavily on them to maintain an active research program. I also have become involved in monitoring the water quality of local lakes and their tributaries to assess the sources of nutrients to lakes and how these nutrient loads influence the water quality of individual lakes.

Current Projects in Stream Ecology:

        I have several projects that my students are working on currently. Two of these are located in the Adirondack Mountains (see below): one is studying small streams and the other is in large rivers.  I also have two on-gong studies in local streams close to Colgate; these are examining how stream macroinvertebrates are influenced by inputs from coniferous versus deciduous forests. Small streams that flow through forests have overhead canopies that reduce light and restrict the amount of algae that grows in these streams. Thus, in-stream production of carbon by algae is very low and you might then expect the numbers of macroinvertebrates to be low. However, these forested streams receive carbon inputs from the forests in the form of leaves, needles, sticks and twigs and there are stream macroinvertebrates (shredders) that break down these large, coarse particulates into fine particulates. In addition to shredders, there are other stream macroinvertebrates (collectors) that are adapted specifically for collecting the smaller particles generated by the shredder activity. In contrast to streams in forested regions, streams with more open canopies (e.g., agricultural streams), have higher light intensities and they possess dense algal mats that are fed upon by grazing macroinvertebrates. In these open canopy streams, shredders are rare or absent because of a lack of coarse particulates and likewise, grazing macroinvertebrates are absent or rare in many forested streams.

        The goal of my research is to determine the ability of macroinvertebrates to use conifer needles versus deciduous leaves as a source of energy by examining macroinvertebrate communities in streams that flow through both conifer and deciduous forests. The stream macroinvertebrate species composition may differ between these sites because in deciduous forests the inputs of leaves are pulsed in autumn whereas for conifer forests the needles fall throughout an annual cycle. Also, when deciduous forests drop their leaves, the canopy opens up, light intensities increase and algal mats often form. Thus, deciduous forest streams have both terrestrial as well as in-stream algal sources of carbon that would be very different from conifer forests. We therefore expect to see differences in the macroinvertebrate communities in the different forest types. Also, we are looking at the influence of the loss of the canopy in deciduous forests by artificially shading sections of deciduous forest streams (80% light reduction similar to the intact canopy) using greenhouse shade cloth. This allows us to keep algal levels low in these artificially shaded sections and compare the macroinvertebrate communities in these sections versus sections with the more open canopies where algal levels are at higher natural densities.

        I also am initiating research in two regions of the Adirondack Mountains.  One project involves determining the impact of water releases from the Abanakee Dam into the Indian River to support a white-water rafting enterprise.  Releases raise the water level in the Indian River by 0.4-0.5m four days each week from June through early September.  These releases scour much of the river bottom and result in a highly disturbed system.  In collaboration with a stream geomorphologists (Dr. Martin Doyle, UNC-Chapel Hill), we are examining the effects of variation in discharge in the Indian River and comparing this community to other local rivers in order to assess the relative impacts of these releases on periphyton and macroinvertebrate communities in the Indian River, the Upper Hudson River above and below its confluence with the Indian River (the latter site would also be influenced by the water releases) and the Cedar and Boreas Rivers. Because of the dramatic variation in discharge in the Indian and lower portion of the Upper Hudson River, we will be using the variation in discharge regimes in all 4 rivers to test an ecological dominant discharge model that we have patterned after the dominant discharge model used by geomorphologists to identify discharge regimes that have the greatest influence on channelization processes.  We hope to use our model to better understand how discharge affects various ecological processes in river ecosystems.

        The other project in the Adirondack Mountains is a collaborative study with two geologists (Dr. R. April, Colgate University and Dr. M. Hluchy, Alfred University) and a small mammal ecologist (Dr. T. McCay).  We are examining the Ca depletion in Adirondack forest soils due to acid deposition and its impact on terrestrial and aquatic food webs.  There has been a decrease in sulfate deposition in the Adirondacks, but no real improvement in either terrestrial or aquatic ecosystems and some research suggests that Ca depletion in soils as a primary factor in their slow recovery.  My part of this project involves examining the impact of episodic acidification events on stream communities.  We understand the effects of chronic acidification on stream communities, but there is less information on the relative impacts of episodic events such as snowmelt and rainstorm events.  These would be perturbations to the system and could act as a disturbance event not only because of the increased discharge, but also because of the rapid pH decline during these high flow events.  However, we know little about the impacts of these events or how the magnitude and/or frequency of these events might influence the stream community.  We will be measuring both the magnitude and frequency of episodic events in four streams of different susceptibilities to pH shifts.  Also, we will do manipulations simulating episodic acidification events (decrease pH by adding acid but without the increases in discharge) to measure the impact of short-term (two day) episodes and long-term (10 day) episodes on stream communities.  Also, by adding Ca (as CaCl2) and bicarbonates (NaHCO3) we will provide better buffering capacities to examine how these changes might assist us in predicting recovery trajectories by communities in the future as further amelioration of H2SO4 and HNO3 occurs in the future.

Research on Local Lakes:

        We have studied local lakes and their tributaries to examine nutrient inputs and their influence on lake water quality. Of the lakes studied so far, we have identified some tributaries to be strongly influenced by agricultural inputs and these appear to have influenced lake productivity. One lake had no cottages and low nutrient inputs from its tributary, but still had the highest productivity of any of the lakes examined largely because of a resident goose population that contributed significant quantities of phosphorus and nitrogen to the lake. We are continuing this project by adding more lakes to the survey. Our goal is to better understand what sources of nutrients might be most important for a particular lake in order to better focus management plans for any one lake. The lakes are different in basin shape, depth and area characteristics, but to date these morphometric features are less important in determining water quality than the nutrient sources and loading to the lakes.

Teaching Interests:

        My teaching interests include a variety courses most of which are centered around ecology and invertebrate zoology. I teach in the Evolution, Ecology and Diversity course (Biology 211) and enjoy the focus of evolution and how life began and evolved over the last 3+ billion years. I find it very interesting to see how the field of molecular biology is contributing to our understanding of evolutionary relationships among all groups of organisms from bacteria and protozoa to invertebrates, vertebrates and plants. I also teach various field-oriented courses in ecology and will forever enjoy getting students out in the field and showing them how to quantify animal and plant communities. The labs often emphasize how ecologists answer questions by teaching students quantitative techniques in different ecosystems and using a comparative approach among different systems. We compare communities from different lakes, streams, forests, meadows, etc. and try to answer questions concerning community struct[Biology @ Colgate]ure. In my limnology (freshwater ecology) course, we sample lakes throughout the winter and early spring. The students in this course spend the first 5 weeks learning techniques in analyzing water chemistry and various other biotic components in lakes and streams and the last 6-7 weeks they conduct a mini-research project of their own design. This gives students a sense of what it takes to design, conduct and analyze/interpret data and many will continue their research project in subsequent semesters in my research lab. I also teach a course in advanced ecology which focuses on the more quantitative aspects of population and community ecology.  The design of this course is similar to my limnology course with the lab teaching techniques and the students then taking these techniques and applying them to a mini-research project.  I also teach a research tutorial in advanced aquatic ecology where students participate directly in my research program or they may bring with them a project fr[Biology @ Colgate]om the limnology course or from some other experience, but all projects are directly tied to freshwater ecosystems. In addition to these courses in biology, I also teach a course in Earth and Environmental Processes in the Environmental Studies Program and again, I enjoy watching students learn first-hand about ecosystem-level processes by examining the water chemistry of precipitation, groundwater and surface water and determine how geology here and in the Adirondacks affects these processes. Finally, I have taught the capstone course in the Environmental Studies Program where students bring their expertise in environmental biology, economics, geography and geology to a project with an environmental slant.  In 2005, the students in this course worked with an inter-municipal commission to investigate the environmental history, land use change, recreational opportunities and water quality of Sauquoit Creek from its headwaters south of Utica to the mouth of the stream where it enters the Mohawk River in Utica.

Student Research:

·         Jimmy Owens, Lisanne Levy and Elizabeth Wolyniak – Impacts of water releases from Abanakee Dam on ecological processes in the Indian and Upper Hudson Rivers during summer 2004.

·         Sarina Doyle, Erin Shope and Lilien Vo - Impacts of water releases from Abanakee Dam on ecological processes in the Indian and Upper Hudson Rivers during summer 2005.

·         Devin Clifford, Jon Crossett and Patrick McDermott – Frequency and magnitude of episodic acidification events in 4 Adirondack streams and their effect on algal and macroinvertebrate communities in summer 2005.

·         Maureen Lynch and Anne Sammarco – Influence of episodic acidification events on decomposition rates of leaf packs composed of single and mixed leaf species in 4 Adirondack streams.

Other Research Projects:

·        Impact of increased discharge on organic matter transport and abundance and structure of periphyton and macroinvertebrate communities in rivers.  This project is designed to develop a new concept in stream ecology: ecological dominant discharge

·        Impact of episodic acidification events on the structure and function of streams in the Adirondack Mountains.  This project examines the role of episodic acidification events (as opposed to chronically acidified streams) as a disturbance event and determines the impacts of these disturbances on the structure and function of stream communities.

Recent Publications:

Randall L. Fuller and Cathy Desmond*. 1997. Influence of food type on the growth of early and late instars of three mayfly (Ephemeroptera) species. Archiv fur Hydrobiologie 141:1-11.

Randall L. Fuller, Corinne Ribble*, Alexia Kelley* and Emily Gaenzle*. 1998. Impact of stream grazers on periphyton communities: A laboratory and field manipulation. Journal of Freshwater Ecology 13: 105-114.

Randall L. Fuller, Brian Kennedy* and Carl Nielsen*.  2004.  Macroinvertebrate responses to algal and bacterial manipulations in streams.  Hydrobiologia 52: 113-126.

* Indicates students as co-authors.

Recent Paper and Poster Presentations:

Seasonal changes in organic matter, periphyton and macroinvertebrates in a small stream flowing through conifer and deciduous forests and an abandoned farm field. R. Fuller, C. Heise*, J. Molina*, H. Salcedo*, S. Ward*, M. Behum* and E. Zacheim*.  53nd Annual Meeting of the North American Benthological Society, Vancouver, BC.  June 2004.

 Effects of variable discharge regimes on river ecosystems: Impact of frequent water releases from Abanakee Dam on the Indian and Upper Hudson Rivers. Randall Fuller. Rensselaer Polytechnic Institute Conference: Who’s doing what on the Upper Hudson, October 2004.

 Effects of variable discharge regimes on river ecosystems: Impact of frequent water releases from Abanakee Dam on the Indian and Upper Hudson Rivers. Randy Fuller. Adirondack Research Conference, Old Forge, NY.  March 2005.

 Dominant Discharge Analysis of Ecological Processes in Streams.  Martin W. Doyle1, Emily H. Stanley2, David L. Strayer3, Robert B. Jacobson4, John C. Schmidt5, Randy Fuller6, Rebecca Manners1, and Melanie J. Small1. 1Department of Geography University of North Carolina, CB #3220, Chapel Hill, NC, USA, 2Center for Limnology. 54th Annual Meeting of the North American Benthological Society, New Orleans, LA.  June 2005.

 Fish Population Estimates: A Comparison of Methods.  Randy Fuller. Colgate University, Biology Department, Hamilton, NY. 54th Annual Meeting of the North American Benthological Society, New Orleans, LA.  June 2005.

Web Resources For Teaching Ecology/Field Courses.  Kristopher K Wright1 and Randall Fuller2. 1University of Wisconsin-Platteville, Biology Department, Platteville, WI, USA, 2Colgate University, Biology Department, Hamilton, NY, USA.  54th Annual Meeting of the North American Benthological Society, New Orleans, LA.  June 2005 

 Effects of variable discharge regimes on river ecosystems: Impact of frequent water releases from Abanakee Dam on the Indian and Upper Hudson Rivers. Randall Fuller, Sarina Doyle*, Lisanne Levy*, James Owens*, Erin Shope*, Lilien Vo* and Beth Wolyniak*, Biology Department, Colgate University, Hamilton, NY and Martin W. Doyle, Geography Department, University of North Carolina, Chapel Hill, NC.  36th International Binghamton Geomorphology Symposium, Buffalo, NY.  October 2005.