Pre-dam removal surveys: Keys to good survey design for successfully quantifying federal and state listed species
Daelyn A. Woolnough and Shaughn Barnett, Biology Department and Institute for Great Lakes Research, Central Michigan University, Mount Pleasant, Michigan


Abstract:

Unionids are often overlooked for the ecosystem services they provide however these services have recently become highlighted when there are dams that are in need of repair or removal. Michigan has over 2500 dams and over 36% of dams in Michigan are over 50 years old, which is the average lifespan of a dam. Often dams have become obsolete based on their original purpose and thus are targeted for removal to increase hydrologic and ecological connectivity in rivers. In Lyons Michigan, a 156 year old flour mill dam is present on the Grand River but no longer serves an economic purpose and has been deemed a high hazard dam that is in poor structural condition.
We have completed surveys in 6 areas (2 upstream and 4 downstream) around the dam. Each of these 6 areas was physically unique and required flexibility in survey design. We will outline each of these regions, why they needed surveys for Section 7 of the Endangered Species Act and how the surveys were performed. Depths precluded strictly wadable surveys therefore snorkeling and SCUBA were also used as survey techniques. A relocation site was determined as part of the survey and the decisions on determining the potential relocation site will be presented. Only one live federally endangered individual (Epioblasma triquetra) was known from the vicinity of the Lyons dam prior to the survey. Densities of unionid assemblages were also unknown, but were quantified during our surveys.
The survey found a reproducing and dense population of Epioblasma triquetra as well as two State endangered species (Ligumia recta and Toxolasma parvum). Each federally endangered species was tagged with a Passive Integrated Transponder (PIT) tag for ease of locating prior to relocation; the pros and cons of this initial tagging will be discussed.

Biography:

Dr. Daelyn Woolnough is a research assistant professor in the Institute for Great Lakes Research and the Biology Department at Central Michigan University, Mt. Pleasant MI. Her research efforts have focused on unionids and their host fish in a variety of rivers and lakes across North America for over 12 years. She is a member of the Mollusc Specialist Subcommittee for the Committee on the Status of Endangered Wildlife in Canada, the Chair of the Michigan Mollusk Technical Advisory Committee and has been involved in developing and analyzing quantitative mollusk surveys. Dr. Woolnough specializes in spatial analysis, statistics and modeling connectivity/fragmentation in aquatic systems. She has a B.Sc. (Env) with a specialization in Environmental Protection and Environmental Law from the University of Guelph, a Diploma in Marine Geomatics from the College of Geographic Sciences, a M.Sc. in Zoology from the University of Guelph, and a Ph.D. in Ecology and Evolutionary Biology from Iowa State University.