Scientific Investigations Report 2004-5119
By James C. Petersen
Prepared in cooperation with the
National Park Service and the
U.S. Department of Agriculture Forest Service
This
document is available in Portable Document Format (PDF):
SIR2004-5119 (9.64 MB)
To view this document, you need the Adobe Acrobat® Reader installed on
your computer.
(A free
copy of the Acrobat® Reader may be downloaded from Adobe Systems
Incorporated.)
The Buffalo River lies in north-central Arkansas and is a tributary of the White River. Most of the length of the Buffalo River lies within the boundaries of Buffalo National River, a unit of the National Park Service; the upper 24 river kilometers lie within the boundary of the Ozark National Forest. Much of the upper and extreme lower parts of the basin on the south side of the Buffalo River is within the Ozark National Forest.
During the summers of 2001 and 2002, fish communities were sampled at 52 sites in the study area that included the Buffalo
River Basin and selected smaller nearby basins within the White River Basin in north-central Arkansas. Water quality (including nutrient and bacteria concentrations) and several other environmental factors (such as stream size, land use, substrate
size, and riparian shading) also were measured.
A total of 56 species of fish were collected from sites within the Buffalo River Basin in 2001 and 2002. All 56 species also were collected from within the boundaries of Buffalo National River. Twenty-two species were collected from headwater
sites on tributaries of the Buffalo River; 27 species were collected from sites within or immediately adjacent to the Ozark National Forest. The list of species collected from Buffalo National River is similar to the list of species reported by previous
investigators. Species richness at sites on the mainstem of the Buffalo River generally increased in a downstream direction.
The number of species collected (both years combined) increased from 17 at the most upstream site to 38 near the mouth of the Buffalo River. In 2001 and 2002, a total of 53 species of fish were collected from sites outside the Buffalo River Basin.
Several fish community metrics varied among sites in different
site categories (mainstem, large tributary, small tributary, headwater, and developed out-of-basin sites). Median relative abundances of stonerollers ranged from about 25 to 55 percent and were highest at headwater and developed out-of-basin sites and lowest at mainstem sites. The relative abundances at the headwater and developed out-of-basin sites were significantly different from the relative abundances at the mainstem sites. Percentages of individuals of algivorous/herbivorous, invertivorous,
and piscivorous species at headwater sites were significantly
lower than values at mainstem and developed out-of-basin sites. Percentages of individuals of invertivorous species at mainstem sites were significantly higher than values at small tributary, headwater, and developed out-of-basin sites. Percentages
of top carnivores at mainstem sites were significantly higher than values at tributary and headwater sites. The numbers
of darter, sculpin, plus madtom species at mainstem, large tributary, and developed out-of-basin sites were significantly higher than values at other sites, and the values at small tributary
sites and headwater sites were each significantly different from values at the other four types of sites. The number of lithophilic
spawning species at large tributary sites was not significantly
different from values at mainstem and developed out-of-basin sites, but values for small tributary and headwater sites each were significantly different from values for all other categories.
Index of biotic integrity scores varied among the site categories.
Scores for mainstem sites were significantly larger than all but large tributary site scores. Scores for headwater sites were significantly smaller than mainstem and large tributary site scores.
Several analyses of the data described in this report suggest
that drainage area is the most important single factor influencing
fish communities of the Buffalo River Basin and nearby basins. Species richness increases with increasing drainage area and some species are restricted to smaller streams while other species are more common in larger streams. Some community metrics also are related to land use and related factors (proportion
of cleared land and nutrient concentrations, for example), suggesting that substantial shifts in basin land use or point-source effluents will have effects on downstream fish communities.
TABLE OF CONTENTS
AccessibilityFOIAPrivacyPolicies and Notices | |