B.Sc.,M.Sc. (Toronto), Ph.D. (Alberta)
Aquatic ecology, behavioural ecology, ecotoxicology
Office Location: Biology Building - 36
Tel: (519) 253-3000 ext. 2725
Fax: (519) 971-3609
My research deals with the ecology, distribution and behaviour of aquatic invertebrates as influenced by natural and human-induced environmental stressors. My students and I study stream and lake habitats in the Great Lakes basin, the Athabasca Oil Sands region of northeast Albertathe, and the Alberta foothills.
Lake-based projects have involved studies of burrowing, lake-dwelling mayflies, midges and amphipods. We have contrasted the relative roles of endogenous effects (dispersal, maternal investment, aggregation, substrate selection) vs. exogenous factors (food, temperature, oxygen, sediment-bound pollutants, etc.) in explaining mayfly growth and survival.This work has evolved into the development of sediment bioassays for mayflies and midges, and studies examining toxicokinetics, genotoxic and teratogenic effects.
Studies of wetlands in the oil-sands region of northeastern Alberta have focussed on comparing successional processes of the zoobenthic communities developing in natural and constructed wetlands as well effects of oil sands mining process water on community development.
Stream studies have dealt with group formation and filter feeding among black fly larvae. I have found that larvae will select specific positions and body postures relative to their neighbours that maximize their feeding rates. The best positions change with food levels and flow patterns. Game theory models can be used to explain changes in individual positioning behaviour and transitions from aggregation to uniform spacing. Black flies are also important bioprocessors, capturing and transforming dissolved organic matter into particles that become available for consumption by other zoobenthos.
Our lab works collaboratively with other researchers and their students on multifaceted problems in large systems. We are currently involved in 3 coordinated projects - studies of Lake Erie, development of Great Lakes basinwide indicators of environmental conditions, and carbon dynamics and food web structure of northern Alberta wetlands. Graduate student opportunities are available with each of the projects.
The Lake Erie Trophic Status Collaborative Study (LETS): Investigating Mechanisms and Extent of Internal Phosphorus Loading
The LETS study has involved 27 scientists studying distribution and flux of biomass and nutrients to clarify mechanisms and extent of internal phosphorus movement, especially relating to DO depletion in central L. Erie. Open water and nearshore attributes vary at different scales and respond to different proximal factors. Total phosphorus (TP) loadings since 1990 have been determined mainly by regionally regulated annual variation in tributary discharges. Central basin TP concentrations have tended to rise since the 1990s. TP concentration and hypolimnetic oxygen depletion (HVOD) rates correlate with loadings of the previous year but not the current year. When values are adjusted for these variations in loadings, TP and HVOD are not different than values of the 1980s prior to arrival of dreissenids. Basin and seasonally-averaged chlorophyll a concentrations are poorly or uncorrelated with TP levels. In contrast, nearshore processes appear to reflect local effects of benthic-pelagic coupling among water clarity, nutrients, benthic primary production, dreissenid distribution & abundance, and round goby distribution & production. These features vary on shorter time scales and are affected by the adjacent landscape. Models of L. Erie dynamics should track and integrate processes in nearshore zones with open water compartments. Interim results of the research are presented in a special issue of the Journal of Great Lakes Research 2005 (Volume 31: Supplement 2).
The Great Lakes Environmental Indicator project: Developing, Evaluating, and Integrating Biological Indicators of Environmental Conditions at Great Lakes coastal margins.
The Great Lakes Environmental Indicators (GLEI) project was begun in 2000. The goal of the research is to find easily measured biological indicators that can tell us about the ecological health of wetlands and shorelines across the entire Great Lakes coast. This is a challenge because the Great Lakes cover such a wide geographic area and because so many different kinds of human activity can affect the biota.
To decide where to collect samples, the drainage basin of each of the 731 streams and rivers flowing into the US Great Lakes was mapped. We then summarized the all available data describing 214 different types of human activity in each drainage basin. Statistical analyses showed that we could summarize this information in terms of 7 general classes of “environmental pressure” (agricultural and fertilizer effects, urbanization, deposition of airborne pollutants, changes to the shoreline, industrial discharges, etc.). We then calculated the amount of each type of environmental pressure for every part of the Great Lakes coastline. We used these summaries to pick suitable biological sampling locations. We wished to measure the biota at places ranging from the least affected by human activity to those that were most affected by each of the types of pressure.
Twenty-nine principal investigators sampled a wide variety of biota (wetland plants, algae, aquatic invertebrates, fish, amphibians, and birds) from more than 300 locations across the 5 Great Lakes. The data are being used to document how the numbers and kinds of these biota change in relation to the different intensities and types of disturbance.
Some of the most promising biological indicators we have found include monitoring the numbers of bird species as a measure of urban impacts, fish community health in cattail and bulrush wetlands as indicators of agricultural impacts and population density, and frog species composition as a measure of overall habitat quality. These measurements are helping us identify the amounts and types of human activity that can sustain a diverse and healthy ecosystem in a particular area.
Carbon Dynamics, Food Web Structure, and Reclamation Strategies in Athabasca Oil Sands Wetlands (CFRAW).
Wetlands will make up 20-40% of the final restored landscape in areas that have been surface mined for oil sands in northeastern Alberta. Over the past 5 years, seven oil sands mining partners and a consortium of university researchers have formed a collaborative group that has built understanding of the effects of mine tailings and process waters on wetland communities. Young constructed wetlands, especially those amended with reclamation materials quickly become productive. Having learned the characteristics of both young and older local wetlands, we can now predict the time required more natural conditions to evolve in constructed systems. We can also assess the pathways and relative environmental risk associated with the dynamics of mine process-associated constituents that are part of constructed wetlands. Our present research is testing these predictions.
We also do not know how productivity of new wetlands is maintained. Natural wetlands slowly accumulate plant materials (organic carbon) from algal production, aquatic plants, and influx of outside materials. inoculating new wetlands with stockpiled peat or topsoil is thought to accelerate succession and community development. The residual hydrocarbons in mine tailings (bitumen) and process water (naphthenic acids) are initially toxic, but may ultimately serve as a surrogate source of carbon once they degrade and/or are metabolized by bacteria. The CFRAW project is documenting how tailings in constructed wetlands modify maturation leading to natural conditions in a reclaimed landscape. Our research is documenting how different sources of biomass are incorporated into the food web as wetlands age; how this influences community development, food web structure and complexity, and the productivity and health of fish and wildlife; and whether wetlands built with peat amendments can be expected to maintain their productivity and ultimately become true peat lands. We are building a conceptual model of carbon pathways and budgets to assess how the allocation of carbon among compartments changes as wetlands mature. Ultimately we will be able to recommend the materials and strategies most effective and economical in producing a functioning reclamation landscape.
Potential Projects for New Students
Bachteram, A.M., K. Mazurek and J.J.H. Ciborowski. 2005. Sediment suspension by burrowing mayflies (Hexagenia spp., Ephemeroptera: Ephemeridae)). Journal of Great Lakes Research 31 (Supplement 2): 208-222.
Bhagat, Y., J.J.H. Ciborowski, L.B. Johnson, T.M. Burton, D.G. Uzarski, S.A. Timmermans. 2007. Testing a fish index of biotic integrity for great lakes coastal wetlands: stratification by plant zones. Journal of Great Lakes Research33 (Suppl.3):224-235..
Brazner, J.C.,N.P. Danz, G.J. Niemi, R.R. Regal, A.S. Trebitz, R.W. Howe, J.M. Hanowski, L.B. Johnson, J.J. H. Ciborowski, C.A. Johnston, E.D. Reavie, V.J. Brady, and G.V. Sgro. 2007. Evaluating geographic, geomorphic and human influences on Great Lakes wetland indicators: multi-assemblage variance partitioning. Ecological Indicators 7: 610-635.
Corkum, L.D., J.J.H. Ciborowski and D.M. Dolan. 2006. Predicting the timing of Hexagenia (Ephemeridae: Ephemeroptera) mayfly swarms in Lake Erie of the Laurentian Great Lakes. Canadian Journal of Zoology 84:1616-22.
Danz, N.P, G.J. Niemi, R.R. Regal, T. Hollenhorst, L.B. Johnson, J. Hnowski, R. Axler, J.J.H. Ciborowski, T. Hrabik, V.J. Brady, J.R. Kelly, J.C. Brazner, R.W. Howe & G.E. Host. 2007. Integrated measures of anthropogenic stress in the U.S. Great Lakes basin. Environmental Management39:631-647.
Grigorovich, I.A., M. Kang, and J.J.H. Ciborowski. 2005. First record of Gammarus tigrinus a new Great Lakes invader. Journal of Great Lakes Research 31: 333-342.
Hobbs, B.F., S.A. Ludsin, R.L. Knight, P.A. Ryan, J. Biberhofer & J.J.H. Ciborowski. 2002 Fuzzy cognitive mapping as a tool to define management objectives for complex ecosystems. Ecological Applications 12:1548-1565.
Hollenhorst, T., T.N. Brown, L.B. Johnson, J.J.H.Ciborowski & G.E. Host. 2007. A multi-scale watershed delineation approach for developing ecological indicators of Great Lakes coastal ecosystems. Journal of Great Lakes Research. 33 (Suppl. 3): 13-26.
Host, G.E., J.A. Schuldt, J.J.H.Ciborowski, L.B. Johnson, T.P. Hollenhorst, and C. Richards. 2005. Use of GIS and remotely sensed data for a priori identification of reference areas for Great Lakes coastal ecosystems. International Journal of Remote Sensing 26: 5325-5342.
Krieger, K.A., M.T. Bur, J.J.H. Ciborowski, D.R. Barton & D.W. Schloesser. 2007. Distribution and abundance of burrowing mayflies (Hexagenia spp.) in Lake Erie: Value as a lake quality indicator. Journal of Great Lakes Research 33 (Suppl. 1):20–33.
Matisoff, G., and J.J.H. Ciborowski. 2005. Lake Erie Trophic Status collaborative study. Journal of Great Lakes Research 31 (Supplement 2):1-10.
Patterson, M., J.J.H. Ciborowski, and D.R. Barton, and. 2005. Dreissenid abundance and size structure in Lake Erie: 2001-2002. Journal of Great Lakes Research 31 (Supplement 2): 223-237.
Smits, J.E., G.R. Bortolotti, M. Sebastian & J.J.H. Ciborowski. 2005. Spatial, temporal, and dietary determinants of organic contaminants in nestling tree swallows in Point Pelee National Park, Ontario, Canada. Environmental Toxicology and Chemistry 24: 3159-3165.