Event Title
Low-Head Dam Removal Positive Affects on Macroinvertebrate Community Structure
Presentation Type
Poster/Portfolio
Presenter Major(s)
Biology
Mentor Information
Eric Snyder, snydeeri@gvsu.edu
Department
Biology
Location
Henry Hall Atrium 5
Start Date
13-4-2011 11:00 AM
End Date
13-4-2011 12:00 PM
Keywords
Environment
Abstract
Dams are added to rivers for many reasons, including flood prevention and reservoir creation. Many of these dams are reaching the end of their life span, and must be either repaired or removed. We studied the removal of the Nashville Dam on the Thornapple River in Barry County, MI, by comparing three up- and three down-stream reaches. One year post-removal, we found that the percent EPT on artificial substrate increased from an average of 27.07 to an average of 63.77 at all sites below the former reservoir. Further, in 2009 Isopods dominated the site directly below the dam, exceeding 2,000 individuals per artificial sampler, while an average of 222 Isopods were found at all downstream sites. In contrast, in 2010 we found an average of 4 isopods per artificial sampler at all of the downstream sites combined. Our results demonstrate that the removal of a low-head dam improved the macroinvertebrate community immediately below the dam. This was in contrast to a decline in habitat quality.
Low-Head Dam Removal Positive Affects on Macroinvertebrate Community Structure
Henry Hall Atrium 5
Dams are added to rivers for many reasons, including flood prevention and reservoir creation. Many of these dams are reaching the end of their life span, and must be either repaired or removed. We studied the removal of the Nashville Dam on the Thornapple River in Barry County, MI, by comparing three up- and three down-stream reaches. One year post-removal, we found that the percent EPT on artificial substrate increased from an average of 27.07 to an average of 63.77 at all sites below the former reservoir. Further, in 2009 Isopods dominated the site directly below the dam, exceeding 2,000 individuals per artificial sampler, while an average of 222 Isopods were found at all downstream sites. In contrast, in 2010 we found an average of 4 isopods per artificial sampler at all of the downstream sites combined. Our results demonstrate that the removal of a low-head dam improved the macroinvertebrate community immediately below the dam. This was in contrast to a decline in habitat quality.