Trout Use of Woody Debris and Habitat in Appalachian Wilderness Streams of North Carolina

Abstract

Ahstrcrcr.-Wilderness areas in the Appalachian Mountains of North Carolina are set aside to preserve characteristics of both old-growth and second-growth forests and associated streams. Woody debris loadings, trout habitat, and trout were inventoried in three southern Appalachian wilderness streams in North Carolina by the basin-wide visual estimation tcchniquc. Two strcnms in old-growth wilderness areas contained more large woody debris (LWD, diameter > IO cm) and more and smaller pools and riffles than did a stream in a second-growth area managed as wilderness. Furthermore, the size distribution of woody debris in the second-growth stream was skewed to smaller size-classes than that in the old-growth streams. Brook trout Saivrlirzu.s,fhnfirzolis. rainbow trout 0ncorhynchu.s mykis.s, and brown trout S&no tr~tta in the three streams were always found in habitat units that had large amounts of LWD but were present in only 70-90'51 of the large number of units with little or no LWD. In the absence of high fishing pressure, the stream with large amounts of LWD supported higher trout density and biomass than the stream with little or no LWD. These old-growth streams provide a benchmark against which recovery of previously disturbed streams may be compared. Furthermore, if the goal for restoration of trout habitat is to recreate old-growth stream conditions, these two old-growth wilderness streams provide a basis for selecting appropriate amounts and sizes of LWD.

Nature and Functions of Cover for Riverine Fish.

“…However, in most field studies where confounding factors are numerous, it has been found that the presence of cover has no (SAUNDERS and SMITH, 1962;FAUSCH and NORTHCOTE, 1992;FAUSCH et al, 1995;FLEBBE and DOLLOFF, 1995;GOWAN and FAUSCH, 1996;HARVEY, 1998) or even a negative effect (WILZBACH et al, 1986) on growth although increased growth rates are sometimes attributed to the presence of rootwad cover (NIELSEN, 1992) or riparian cover (VILA-GISPERT et al, 2000). Results obtained in laboratory experiments are also equivocal due to difficulties in defining working hypotheses and to methodological problems (e.g.…”

Factors influencing wood mobilization in streams

“…Wood pieces provide stable substrate for invertebrates and biofilms, entrap leaves and other organic matter, afford overhead cover for fish, promote hyporheic exchange flow and transient storage, enhance hydraulic heterogeneity, and encourage pool formation and channel meandering [Angermeier and Karr, 1984;Beechie and Sibley, 1997;Gregory et al, 2003;Johnson et al, 2003;Mutz and Rohde, 2003;Eggert and Wallace, 2007;Stofleth et al, 2008]. The frequency and character of wood inputs varies in space and time [Latterell and Naiman, 2007;Golladay et al, 2007] and is strongly affected by riparian management [Flebbe and Dolloff, 1995;Angradi et al, 2004;Kreutzweiser et al, 2005;Czarnomski et al, 2008].…”

Forestry Best Management Practices Relationships with Aquatic and Riparian Fauna: A Review

“…SMZs provide coarse woody debris and detritus inputs that serve as food and habitat structure for aquatic species [109][110][111][112] and critical microhabitat for riparian organisms for nesting, roosting, feeding, or breeding. Implementation requirements and subsequent success of an SMZ depends on the aquatic species of concern, and to what extent managers need to protect riparian and aquatic ecosystems from disturbance [47].…”

“…Woody debris is typically generated during harvesting operations, and riparian buffers can be managed to provide woody debris input into aquatic ecosystems [39,[110][111][112]125,126]. Although additional nutrient inputs sometimes can enhance fish habitat in headwater streams, in some cases, these inputs could stimulate downstream eutrophication [2].…”