My research focuses on the effectiveness of man-made wetlands and ponds as habitat for amphibians.  Specifically, I’m interested in improving the construction and placement of compensatory mitigation and other constructed aquatic sites in order to conserve rare and declining amphibian species.  As natural habitat is degraded or destroyed by development and agriculture, restoration and creation of replacement habitat has the potential to play a vital role in amphibian conservation.  However, this potential will be squandered without understanding the basic ecological needs of amphibians at both the meta-population and local population levels.  Once these needs are understood, they can be applied during planning and construction phases of new wetlands.

Evaluating the Effectiveness of Mitigation and other Constructed Aquatic Sites

I am conducting a joint research effort between the Missouri Department of Transportation (MoDOT), the Missouri Department of Conservation (MDC), and the University of Missouri.  MoDOT is required by Section 404 of the Clean Water Act to obtain permission from the U.S. Army Corps of Engineers (USACE) whenever wetlands are affected by highway construction and maintenance.  Permission is granted to MoDOT based on their efforts to avoid, minimize, or mitigate (replace) the wetland.  The mitigation wetlands that are created are either the same size or larger than the original wetland because federal and state executive orders require no net loss of wetlands.  MoDOT, along with the USACE, monitor the replacement wetlands to ensure that they are developing the correct hydrology and vegetation.  However, evaluation of the replacement wetlands as wildlife habitat is generally not performed because it is assumed that if the correct hydrology and vegetation develop, wetland fauna (including amphibians) will colonize the replacement wetland.

The Missouri Department of Conservation also creates a variety of aquatic habitats on its lands in order to provide for the needs of a wide range of fauna.  These can range from large tracts of carefully controlled floodplain wetlands to small “wildlife ponds” in upland areas.  These small ponds are intended to enhance the conservation of many animal species, including amphibians.  Although they are not created to replace wetland functions lost due to development, many of these ponds provide aquatic habitat that is similar to mitigation wetlands.  For example, some of these wildlife ponds have shallow vegetated fringes and some dry down considerably during summer months and develop emergent or floating vegetation throughout.  Conversely, some mitigation wetlands contain areas of deep (> 1 m), open water similar to many wildlife ponds.  Regardless of the initial reason for construction of the site (mitigation vs. conservation), the intended outcomes of each are the same – wildlife, including amphibians, are expected to use and colonize the sites.

The natural environment in northern Missouri, like that of many Mid-western states, is a patchwork of habitat fragments.  These fragments are often interspersed by development or agriculture.  Studies have shown that both act as barriers to wildlife movement, including amphibian migration and dispersal.  Because of this, despite the construction of new aquatic habitat, many species of amphibians may lack effective abilities to migrate and colonize these sites if they are separated by these barriers, or by sheer distance.  Translocation of amphibian eggs may provide an answer to this problem, provided that other ecological needs are met at both the local and landscape level.

My intent with this project is to examine both the “build it and they will come” philosophy, and the feasibility of translocation of amphibians to newly created sites.  Ultimately, I wish to provide each agency with information that will assist them in their efforts to construct aquatic habitat that will benefit amphibians in need of conservation.

The phases of my research are:

1. Examine the effectiveness of current Missouri Department of Transportation wetland mitigation sites and Missouri Department of Conservation “wildlife ponds” as amphibian habitat.  Both landscape and local habitat variables will be examined for each site included in the study.  The intent is to evaluate how both placement of wetlands in the landscape and “within wetland” design features have affected amphibian colonization.
   
   
2. Create new replicated wetland pools that experimentally examine the effects of various “within wetland” characteristics that have been shown to affect amphibian populations at natural wetlands (from phase 1).
   
   
3. Examine various translocation techniques in order to establish scientifically tested methods for introduction of rare or declining amphibian species into man-made wetlands.

The study is being funded by grants from the U.S. EPA and the Missouri Department of Conservation.  The Missouri Department of Transportation is providing assistance in the form of personnel time and construction cost of experimental wetland pools that will serve a dual role as actual mitigation wetlands.  Dr. Kate Trauth of the MU Division of Civil and Environmental Engineering, and her PhD. student Miriam Romero, are working with us on this project by providing GIS analysis of the landscape components that are being examined in phase 1 of the research.

The Environmental Studies Section of the Missouri Department of Transportation
http://www.modot.mo.gov/services/engineering/environmentalstudies.htm

The Missouri Department of Conservation Home Page
Do a search for “wetlands” from the home page for much more information about Missouri’s wetlands.
www.mdc.mo.gov

United States Environmental Protection Agency Wetlands Website
http://www.epa.gov/owow/wetlands/

The University of Missouri Department of Civil and Environmental Engineering Website
http://www.civil.missouri.edu/html/env/index.html