HR: 09:30h
AN: H21I-06    [Abstracts]
TI: Evaluating the Impact of Barriers on the Fragmentation of Waterbodies Traversed by Migratory Fish
AU: * Meixler, M
EM: msm10@cornell.edu
AF: Cornell University, 104 Rice Hall Department of Natural Resources, Ithaca, NY 14853, United States
AB: Fish migrate to spawn, feed, seek refuge from predators, and escape harmful environmental conditions. The success of upstream migration is limited by the presence of barriers that can impede the passage of fish. If migration is delayed or halted by barriers, the life cycle of that species may be disrupted resulting in decreased population health. Potential barriers to upstream migration include natural structures such as waterfalls, cascades and debris dams and artificial barriers such as culverts and dams. Some barriers are impassable at all levels of flow to all species while other barriers may experience periods with favorable conditions for migratory fish. We used geographic information systems (GIS) to assess each barrier's role in blocking migratory fish passage. Using readily available data, we estimated barrier height, the depth of the plunge pool, and the velocity of the water (both estimated at the time of spawning for each species modeled) and the burst swimming speed and jumping ability of non-stocked migratory fish species of interest. A barrier was considered passable if its height was lower than the maximum jumping height of the fish, its plunge pool deeper than the average length of the fish, and the velocity of the water slower than the burst swimming speed of the fish. Model predictions were tested against observed presence/absence data. The map produced from the execution of this model is a useful tool for evaluating the extent of habitat lost to migratory fish as a result of habitat fragmentation by barriers. This information can be used to inform managers concerned about migratory fish population viability and to guide future restoration and conservation efforts.
DE: 1803 Anthropogenic effects (4802, 4902)
DE: 1808 Dams
DE: 1819 Geographic Information Systems (GIS)
DE: 1834 Human impacts
DE: 1847 Modeling
SC: Hydrology [H]
MN: 2007 Fall Meeting