Dr. Brenda Moraska Lafrançois, Aquatic Ecologist, National Park Service

Ph.D., Colorado State University (Ecology), 2002
B.S., University of Wisconsin-La Crosse (Biology and Spanish), 1997

Phone: 651-433-5953 ext. 35
email:

Research Interests

Working for the National Park Service takes me to nine different parks in the Great Lakes area as well as others throughout the Midwest. In each of these parks, diverse aquatic resources intersect with a variety of human influences. This intersection forms the foundation of all my current research activities. I am especially interested in understanding ecological effects of the following anthropogenic stressors:

• Atmospheric contaminants
  Many contaminants are transported to national parks via atmospheric deposition. Mercury deposition, for example, is widespread and high levels of mercury have been measured in fish and aquatic wildlife at each of the Great Lakes parks. Over the past several years, we've investigated patterns of mercury bioaccumulation in crayfish from interior lakes of Voyageurs National Park and worked with partners to initiate pilot mercury studies in lagoon ecosystems of Apostle Islands National Lakeshore. Excess nitrogen deposition also occurs throughout the region, and may be adversely affecting lake and riverine ecosystems. Previous studies show that increased nitrogen availability may induce algal growth and eutrophication in some nitrogen-limited lakes of northern Minnesota and the Rocky Mountains.
• Aquatic invasive species
  The Great Lakes and Upper Mississippi River System have endured many invasions by aquatic nuisance species, and each of the nine parks in this region are threatened by additional invasions. Currently, I'm involved in zebra mussel monitoring and prevention at St. Croix National Scenic Riverway, and am working with partners to determine the effects of zebra and quagga mussel invasions on nearshore ecology at Sleeping Bear Dunes National Lakeshore. I'm interested in the detection and ecological effects of the spiny water flea in inland lakes at several Great Lakes area parks, as well as the effects of rusty crayfish on native crayfish, littoral ecology, and mercury bioaccumulation at Voyageurs National Park.
• Nutrient enrichment
  Primary productivity in aquatic systems is generally limited by the availability of critical nutrients like phosphorus and nitrogen. Human activities and land use changes have increased the availability of these nutrients in many park waters, leading to increases in algal productivity and the frequency of algal blooms. Nutrient enrichment is an especially important management issue at St. Croix National Scenic Riverway and Mississippi National River and Recreation Area. We continue to analyze and interpret long-term water quality monitoring data for these two riverine parks, and are initiating a paleolimnological project to investigate nutrient-related oxygen loss in deeper waters of Lake St. Croix.

Representative Publications

Lafrançois, B.M., K.R. Nydick, B.M. Johnson, and J.S. Baron. Cumulative effects of nutrients and acidity on the plankton of two mountain lakes. Canadian Journal of Fisheries and Aquatic Sciences, in press.

Baron, J.S., K.R. Nydick, H.M. Rueth, B.M. Lafrançois, and A.P. Wolfe. 2005. High elevation ecosystem responses to atmospheric deposition of nitrogen in the Colorado Rocky Mountains, USA. In: Huber, U.M., H.K.M. Bugmann, and M.A. Reasoner, (eds.). Global change and mountain regions: an overview of current knowledge. Advances in Global Change Research, Vol. 23. Dordrecht, The Netherlands: Springer. p. 429-436.

Lafrançois, B.M., K.R. Nydick, and B. Caruso. 2004. Phytoplankton N limitation of phytoplankton in lakes of the Snowy Range (Wyoming, U.S.A.): a lake comparison study. Arctic, Antarctic, and Alpine Research 35(4):499-508.

Nydick, K.R., B.M. Lafrançois, J.S. Baron, and B.M. Johnson. 2003. Lake-specific responses to elevated atmospheric nitrogen deposition in the Colorado Rocky Mountains, USA. Hydrobiologia 510:103-114.

Lafrançois, B.M., D.M. Carlisle, K.R. Nydick, B.M. Johnson, and J.S. Baron. 2003. Environmental characteristics and benthic invertebrate assemblages in Colorado mountain lakes. Western North American Naturalist, 63(2):137-154.

Baron, J.S., H.M. Rueth, A.P. Wolfe, K. Nydick, E.J. Allstott, J.T. Minear, and B. Moraska. 2000. Ecosystem responses to nitrogen deposition in the Colorado Front Range. Ecosystems 3:352-368.