Evaluation of Habitat Enhancement Structure Use by Spotted Bass
in Natural and Experimental Streams
by
Stanley L. Proboszcz
B.S., University of Guelph, 1995
ABSTRACT
A common method used to enhance salmonid
populations is to improve lotic habitat by installing habitat enhancement
structures. However, the effects of enhancement structures have not
been evaluated for spotted bass Micropterus punctulatus. The
objectives of this study were to evaluate use of half-log, rootwad structure,
and LUNKERS (little underwater neighborhood keeper encompassing rheotactic
salmonids), by adult and juvenile spotted bass in natural and experimental
streams. Enhancement structures were installed in Otter Creek, Kansas.
Adult spotted bass use of natural and enhancement structure was documented
weekly during summer and fall of 2001 and 2002 using radiotelemetry.
Mean home range size ws 3,158 m2 (SE = 705 m2).
Selection ratios were high for enhancement structures (half-log = 21.8;
LUNKERS = 4.2; rootwad structure = 1.1) and did not differ significantly
from natural structure. Habitat use by juvenile spotted bass and
the influence of a predator (flathead catfish Pylodictis olivaris)
were evaluated in an experimental stream. Juvenile spotted bass used
enhancement structures similarly to the field study. For example,
half-log had the highest selection ratio (2.1) and no structure (an empty
position) had the lowest (0.1). Mean velocity available was not significantly
different among half-log, rootwad structure, and LUNKERS; however, half-log
and rootwad structure differed from no structure. Mean light intensity
available was lowest for half-log and differed significantly from no structure
and rootwad. Flathead catfish position had not significant effect
on spotted bass habitat selection. These results indicate that juvenile
spotted bass habitat use is a function of low velocity and low light intensity.
In addition, half-log is the most appropriate structure to use for spotted
bass lotic restoration projects and would likely benefit both juvenile
and adult fish in Kansas streams.