Title page for ETD etd-060599-184632


Type of Document Master's Thesis
Author Smith, Ryan Kennerly
Author's Email Address ryan_smith@tnc.org
URN etd-060599-184632
Title Differential stability of spawning microhabitats of warmwater stream fishes
Degree Master of Science
Department Fisheries and Wildlife Sciences
Advisory Committee
Advisor Name Title
Orth, Donald J. Committee Chair
Angermeier, Paul L. Committee Member
Dolloff, C. Andrew Committee Member
Flebbe, Patricia A. Committee Member
Keywords
  • Streambed Hydraulics
  • Stream Habitat
  • Fish Reproduction
  • Fish Habitat Use
  • Life History
  • Stream Ecology
  • Streambed Hydraulics
  • Stream Habitat
  • Fish Reproduction
  • Stream Ecology
  • Life History
  • Fish Habitat Use
Date of Defense 1999-05-20
Availability unrestricted
Abstract
I investigated streambed stability in spawning microhabitats of warmwater fishes in the upper Roanoke River, Virginia. Spawning microhabitats used by four reproductive guilds (egg-clusterers, mound-builders, egg-buriers, and pit-builders) were identified and ranges of 15 microhabitat variables used by each guild were compared to available microhabitat conditions to investigate habitat selection. Habitat usage by egg-clusterers was most characterized by selection for spawning rocks in the cobble size range, substrate roughness elements in the cobble to boulder size range, high roughness Reynolds number and moderate water column velocity. The mound-building bluehead chub (Nocomis leptocephalus) was distinct in its selection of substrate in the small gravel range, low water velocity and non-turbulent flow. Egg-buriers were the least distinct of the four guilds, exhibiting much variation in habitat use among the component species. However, all species used areas with small substrate (sand to gravel range), high velocity, and high turbulence. The pit-building central stoneroller (Campostoma anomalum) was distinct in its usage of areas with high velocity and turbulence, gravel sized substrate, and low embeddedness.

Stability of each guild's spawning microhabitats was empirically evaluated through analysis of tracer particle movement and repeated surveying of bed elevation along stream transects. Logistic regression equations developed from tracer particle data predicted that microhabitats selected by egg-clusterers are among the most stable of all available habitats during high flows. Microhabitats utilized by mound-builders, egg-buriers, and pit-builders are predicted to be less stable. Repeat transect surveying corroborates model predictions in that egg-burier habitats experienced changes in bed elevation in high flows, while egg-clusterer habitats did not.

Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  rksthesis.pdf 338.67 Kb 00:01:34 00:00:48 00:00:42 00:00:21 00:00:01

Browse All Available ETDs by ( Author | Department )

dla home
etds imagebase journals news ereserve special collections
virgnia tech home contact dla university libraries

If you have questions or technical problems, please Contact DLA.