Fish biodiversity, habitat use and population regulation in southern Appalachian forested watersheds.

FISH BIODIVERSITY, HABITAT USE AND POPULATION REGULATION IN SOUTHERN APPALACHIAN FORESTED WATERSHEDS.

Sponsoring Institution

National Institute of Food and Agriculture

Project Status

COMPLETE

Funding Source

MCINTIRE-STENNIS

Reporting Frequency

Annual

Accession No.

0212721

Grant No.

(N/A)

Cumulative Award Amt.

(N/A)

Proposal No.

(N/A)

Multistate No.

(N/A)

Project Start Date

Nov 1, 2007

Project End Date

Oct 31, 2012

Grant Year

(N/A)

Program Code

[(N/A)]- (N/A)

Recipient Organization
UNIVERSITY OF GEORGIA
200 D.W. BROOKS DR
ATHENS,GA 30602-5016

Performing Department
School of Forestry & Natural Resources

Non Technical Summary
The southeastern United States has the highest fish biodiversity in North America and there is a clear positive relationship between the percentage of forested land in a watershed and fish diversity (Jones et al. 1999; Sutherland et al. 2002). However, over the last 20 years, activities that may detrimentally affect forested streams (i.e., road construction, vacation home development, agriculture) have increased in the southern Appalachians (Jones et al. 1999; Sutherland et al. 2002, Sutherland & Meyer 2007). Unfortunately, management efforts to mitigate these disturbances have been limited by a lack of knowledge regarding the effects on fishes of the increased turbidities and fine sediment loads(Bent 2001, Sutherland et al. 2002). Our results will provide essential information for managers in the formulation of strategies for estimating ?ocritical habitat?? and Total Maximum Daily Loads for southern Appalachian fishes. First, we will quantify the habitat relationships for several species in a relatively undisturbed watershed and test the habitat selection models of Grossman et al. (2002) and Petty & Grossman (1996). Second, we will continue to assess the effects of turbidity on foraging success of several stream fishes. Increased turbidity is perhaps the most common water quality problem encountered when proper forestry practices are not followed (Zamor & Grossman 2007). Third, we will link habitat relationships to population dynamics of a sentinel species, brook trout (Salvelinus fontinalis) which may be affected by climate change in the southern Appalachians.

Animal Health Component

(N/A)

Research Effort Categories

Basic

(N/A)

Applied

(N/A)

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
135	0812	1070	25%
135	0899	1070	25%
136	0812	1070	25%
136	0899	1070	25%

Knowledge Area
135 - Aquatic and Terrestrial Wildlife; 136 - Conservation of Biological Diversity;

Subject Of Investigation
0899 - Wildlife and natural fisheries, general/other; 0812 - Fish habitats;

Field Of Science
1070 - Ecology;

Keywords

Goals / Objectives
Objective 1: We will determine the generality of the optimal foraging models developed in Grossman et al. (2002) and Petty & Grossman (1996) via testing on new species, especially those that might be affected by land-use change in forested watersheds. We also will continue refinement of these models. Objective 2: To continue to examine the role of disturbance in the form of invasive species and turbidity on native fishes. We will attempt to determine the status of the yellowfin shiner invasion and determine how potential competition with rosyside dace will be affected when turbidity increases. Objective 3: We will continue studies on the population dynamics of forested stream fish species, including a sentinel species for climate change, brook trout (Salvelinus fontinalis). Mostly this will entail analysis of previously collected data sets, but in some cases experimentation will be performed to elucidate causal mechanisms.

Project Methods
The procedures for these objectives are relatively straightforward and all have been previously published. For Objective 1 we will continue to use the methodologies of Grossman et al (2002) and Henry & Grossman (2007) to test whether drift-feeding fishes and benthic fishes occupy microhabitats that potentially increase their rate of energy gain. For drift-feeders we will conduct laboratory experiments using the methods of Grossman et al (2002) at a variety of velocities to develop prey capture success curves and then use these data to predict the optimal focal point velocity occupied by the species (Grossman et al. 2002). We will then make focal point velocity measurements on fishes in the stream, to test the model prediction. For benthic fishes we will collect benthic prey samples at the position of the fish and at random locations and compare these to determine whether benthic species are selecting patches with higher prey availabilities (Petty & Grossman 1996; Henry & Grossman 2007). For Objective 2 we will perform field work using the snorkeling techniques of (Grossman & Ratajczak) 1998; and Skyfield & Grossman (2007), to determine the upstream distribution of yellowfin shiner. To assess how turbidity and the presence of yellowfin shiner affect foraging success of rosyside dace we will use the methodology of Zamor & Grossman (2007). Experiments will be conducted in a 3.0m X 0.75m X 1.0m Plexiglas artificial stream. Fine red clay will be used as the suspended sediment in varying quantities to attain desired turbidity levels. A Hach Model 2100P turbidity meter will be used to measure turbidity in NTUs (nephelometric turbidity units). During each trial, 20 prey items will be released at 2 minute intervals from one of three randomly selected prey entry points. A high-resolution video camera will be used to later determine the locations of both prey and fish and calculate reactive distances. We will compare foraging success, reactive distance, and aggression rates among intra and interspecific groups of competitors at two densities (2 & 4 fish), a minimum of three turbidity levels (10, 20, & 30 NTUs), 12 & 20 cm/s velocity, and spring temperatures (10-12C). Finally, for Objective 3 we will use both the descriptive and if necessary the experimental methods of Grossman et al (2006) to determine the relative importance of density-dependence, density-independence, recruitment limitation, and habitat limitation on selected water-column and benthic species including brook trout. If addition field data collection occurs, research sites will be sampled during the spring and autumn sample each year. We will use the sampling methodology of Freeman et al. (1988), involving three sequential electrofishing passes (Smith-Root [Vancouver, Washington, USA] Model LR 24 electrofisher) of constant effort through a site that is block-netted at both ends. This method has yielded population estimates with low variances and is sufficient for the questions being addressed. We will use a three-pass depletion estimator (Program Capture) to derive abundance estimates for the total population and each life-history class separately (YOY, juveniles, adults).

Progress 11/01/07 to 10/31/12

Outputs
OUTPUTS: INVITED LECTURES 2012 Stream biodiversity in the Southern Appalachians with thoughts about Mississippi applications, Univ. Mississippi, 2011 A 30 year look at southern Appalachian (USA) stream fishes or why I divorced community ecology for stream ecology. University of Otago, New Zealand. Innovative approaches to habitat selection and biodiversity regulation in southeastern fishes. Univ. Georgia Fish. Soc. 2010 Effects of flow variation on fish assemblage structure and microhabitat use. Canadian Hydronet Workshop, Montreal, 2008 The importance of interactive versus individualistic processes in a southern Appalachian stream fish assemblage. Tulane Univ, LA The importance of interactive versus individualistic processes in a southern Appalachian stream fish assemblage. University of Lisbon, Lisbon, Portugal. The importance of interactive versus individualistic processes in a southern Appalachian stream fish assemblage. Univ. North Carolina, Chapel Hill, NC. Grossman, G.D. et al. Long-term population dynamics of a southern brook trout population. Am. Fish. Soc. Ann. Meet,, Nashville TN Grossman, G.D. et al. 2009. Demographic regulation of a southern brook trout population. N. Am. Benthological Soc. Ann. Meeting, Grand Rapids MI, Elkins, D. & G.D. Grossman. 2009. The effects of rainbow trout introductions on native fishes in a southern Appalachian stream. Am. Fish. Soc. Ann. Meet, Nashville TN. This paper won an honorable mention in the student paper competition. Hazelton, P. & G.D. Grossman. 2009. Turbidity, velocity and competition affect foraging success in rosyside dace and yellowfin shiner. Am. Fish. Soc. Ann. Meet., Nashville TN Grossman, G.D.. Habitat selection in southern stream fishes. Southern Division, Am. Fish. Soc. Ann. Meet,, Asheville, NC. Grossman, G.D. Effects of flow variation on fish assemblage structure and microhabitat use. Hydronet Workshop, Montreal, Canada Grossman, G.D. et al. Long-term population dynamics of a southern brook trout population. South. Div., Am. Fish. Soc., Ann. Meet., Asheville, NC. Grossman, G.D. & Ratajczak, R. Macorinvertebrate diversity in a southern Appalachian stream, a test of the Intermediate Disturbance Hypothesis. N. Am. Benthological Soc. Ann. Meeting, Santa Fe, NM Grossman, G.D. & Ratajczak, R. Population regulation in some southern Appalachian stream fishes. SE Fishes Council, Ann. Meeting, Athens, GA. Elkins, D. Nibbelink, N & G. Grossman. LOCOH in an artificial stream: using a GIS to map the effects of rainbow trout on native minnows. SE Fishes Council, Ann. Meeting, Athens, GA. Gotelli, N. Dorazio, R, Ellison, A. & G. D. Grossman Measuring temporal change in community structure. Biological Diversity in a Changing World, Royal Society London, Grossman, G.D. & Ratajczak, R. Population regulation in some southern Appalachian stream fishes. N. Amer. Benthological Society Annual Meeting, Providence, RI Grossman, G.D. Not all drift feeders are trout, American Fisheries Society, Ann. Meeting, Seattle, WA Am. Fish. Soc., Annual Meeting Innovative approaches to habitat selection and biodiversity regulation in southeastern fishes. University Georgia Fisheries Society, Athens, GA PARTICIPANTS: We did some collaborative work with Professor Raymond P. Morgan, from the University of Maryland Center for Environmental Science, examining the genetics of brook trout in our study site. We found that our site contained pure southern brookies and they have very low average hererozygosity. We also did a collaborative project with Dr. Troy Zorn and Andy Neufer on Population Regulation in Michigan Brook trout (Salvelinus fontinalis) TARGET AUDIENCES: Target audiences are both the scientific community as well as the general public. PUBLIC LECTURES From tulip trees to Tricoptera to trout: how streams work in the southern Appalachians. Southeastern Chapter Conclave, Federation Fly Fishers, Calloway Gardens, GA A different view of trout: how streams work in the southern Appalachians. RabunChapter, Trout Unlimited, Clayton, GA PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Work from MS-144 fell into three categories: studies of fish assemblage structure, population regulation, and foraging success. Studies of fish assemblage structure yielded a novel explanation for the pattern of increasing fish diversity as one moves downstream (Grossman et al. 2010a). We established that the gradient in fish diversity in the Coweeta drainage is produced by the differential abilities of fish to move upstream against the current (Grossman et al. 2010) rather than by resource limitation. Additional work focused on development and application of a new statistical approach to linking patterns in physical data with fish assemblage structure data in Coweeta Creek and several other systems using Multivariate Autoregressive Models (Grossman & Sabo 2010). Finally, we developed new randomization tests combined with hierarchical models to test for random species occurrences and population variation, undetected species, and covariation in long-term community data sets (Gotelli et al. 2010). The second aspect of our research involved elucidating the mechanism of population control in fish species occupying forested watersheds focusing on southern brook trout in the Ball Creek, and a northern brook trout population in Hunt Creek MI. We examined the importance of density-dependent and density-independent processes in both northern and southern brook trout using 13 (Grossman et al. 2010b) and 50 year (Grossman et al. 2012) data sets respectively. We found that strong density dependence was present in most population segments in both populations. Finally, mark-recapture analysis indicated that gilt darter moved both long and short distances with 40% of all recaptures occurring within 5 m of the initial capture point. The final aspect of our project dealt with studies of habitat selection and turbidity effects on fish assemblage members. Our studies of the effects of the invasive yellowfin shiner and turbidity on the native rosyside dace demonstrated that both interspecific competition and increasing turbidity had significant negative impacts on foraging success of rosyside dace (Hazelton & Grossman 2009a,b; Wagner & Grossman in press. We also showed that the distribution of rosyside dace and mottled sculpin conformed to the Ideal Free or Ideal Despotic Distributions, demonstrating that these species chose microhabitats based on their net energy gain and were able to assess the profitability of different habitat patches in forested streams (Petty & Grossman 2012; Wagner & Grossman in press). Finally, we continued studies of microhabitat use in stream fishes occupying forested habitats as well as tests of an energy-maximization habitat selection model for benthic stream fishes. Our test of the energy-maximization model in three darter species yielded mixed results. Both blackbanded and tessellated darters occasionally occupied microhabitats that had higher proportions of their Diptera prey than expected by random, although this never was observed in a third less abundant species turquoise darter Henry, B.E., and G. D. Grossman. 2008).

Publications

Grossman, G.D., Nuhfer, A. Zorn, T. Sundin, G. & G. Alexander. 2012. Population regulation of brook trout (Salvelinus fontinalis) in Hunt Creek Michigan: a 50-year study. Freshwat. Biol.57, 1434-1448
Grossman, G.D 2012. Ask Dr. Trout .American Angler Magazine January-February issues, p. 10
Grossman, G.D 2012. Ask Dr. Trout .American Angler Magazine March-April issue. p.15.
Grossman, G.D 2012. Ask Dr. Trout .American Angler Magazine May-June issue. p. 12.
Grossman, G.D 2012. Ask Dr. Trout .. American Angler Magazine, July-August issue. p. 11.
Grossman, G.D 2012. Ask Dr. Trout .. American Angler Magazine September-October issue. p. 13.
Grossman, G.D 2012. Ask Dr. Trout .American Angler Magazine November-December issue. p. 11
Wagner, C. M. & G. D. Grossman. 2012. Ideal invaders: an invasive minnow tracks prey resources better than a native species. Ecol. Freshwat. Fish: in press (11 journal pp.).

Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: Scientific Presentations Grossman, G.D. & Ratajczak, R. Population regulation in some southern Appalachian stream fishes. North American Benthological Society Annual Meeting, Providence, RI Grossman, G.D. Not all drift feeders are trout, American Fisheries Society, Annual Meeting, Seattle, WA American Fisheries Society, Annual Meeting Invited Lectures: Innovative approaches to habitat selection and biodiversity regulation in southeastern fishes. University Georgia Fisheries Society, Athens, GA I was an Evans Visiting Fellow at Otago University, Dunedin, New Zealand and presented the following: A 30 year look at southern Appalachian (USA) stream fishes or why I divorced community ecology for stream ecology. Dept. Zoology, University of Otago, Dunedin, New Zealand. Parallels and contrasts in sculpture and science: a practitioner's view. Distinguished Communicator Lecture Series, Centre for Science Communication, University of Otago, Dunedin, New Zealand. Popular Publications: Ask Dr. Trout 2011. American Angler Magazine January-February, p. 10 Ask Dr. Trout 2011. American Angler Magazine, March-April, p. 8. Ask Dr. Trout 2011. American Angler Magazine, May-June, p.13. Ask Dr. Trout 2011. American Angler Magazine, July-August, p.11. Ask Dr. Trout 2011. American Angler Magazine, September-October, p.10. Ask Dr. Trout 2011. American Angler Magazine, November-December, p.12. PARTICIPANTS: We are continuing our work on a collaborative project with Dr. Troy Zorn and Andy Neufer which involves comparative studies of population regulation in Michigan and North Carolina brook trout (Salvelinus fontinalis) populations. TARGET AUDIENCES: Target audiences are the scientific community and the general public. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Brook trout microhabitat use surveys were conducted in the spring, summer, and fall of 2011 in order to quantify microhabitat use by different size class brook trout. Individual fish were PIT-tagged during the spring and fall of 2011 to monitor movement within the study site between seasons. This study will be continued into the 2012 year. We are continuing the analyses of how density dependent and density independent factors influencing population variation in the fish assemblage of Coweeta Creek from 1984-2004. The species in this analysis are the longnose dace, rosyside dace, mottled sculpin and rainbow trout. We have started on analysis of previously collected benthic samples in conjunction with the gilt darter microhabitat use study by Skyfield and Grossman 2007. These benthic samples were collected at darter locations and random locations in Coweeta and Tellico Creeks, NC. We plan to duplicate these gilt darter microhabitat observations and benthic macroinvertebrate collections at these sites in the coming year. We submitted a manuscript examining the utility of direct observational methods for assessing competitive interactions between invasive and native freshwater fishes.

Publications

Alemeida, D., Almodovar, A., Nicolac, G., Elvira, B. & G. Grossman. 2012. Trophic plasticity of invasive juvenile largemouth bass Micropterus salmoides in Iberian streams. Fisheries Res. 113:153-158.

Progress 01/01/10 to 12/31/10

Outputs
OUTPUTS: Scientific Presentations Grossman, G.D.. Habitat selection in southern stream fishes. Southern Division, American Fisheries Society, Annual Meeting, Asheville, NC. Grossman, G.D. Effects of flow variation on fish assemblage structure and microhabitat use. Hydronet Networking Workshop, Montreal, Canada Grossman, G.D. & 3 co-authors Long-term population dynamics of a southern brook trout population. Southern Division, American Fisheries Society, Annual Meeting, Asheville, NC. Grossman, G.D. & Ratajczak, R. Macorinvertebrate diversity in a southern Appalachian stream, a test of the Intermediate Disturbance Hypothesis. North American Benthological Society Annual Meeting, Santa Fe, NM Grossman, G.D. & Ratajczak, R. Population regulation in some southern Appalachian stream fishes. Southeastern Fishes Council, Annual Meeting, Athens, GA. Elkins, D. Nibbelink, N & G. Grossman. LOCOH in an artificial stream: using a GIS to map the effects of rainbow trout on native minnows. Southeastern Fishes Council, Annual Meeting, Athens, GA. Gotelli, N. Dorazio, R, Ellison, A. & G. D. Grossman Measuring temporal change in community structure. Biological Diversity in a Changing World, Royal Society London, England Popular Publications: Ask Dr. Trout 2010. American Angler Magazine January-February issue. p. 10. Ask Dr. Trout 2010. American Angler Magazine May-June issue. p. 12. Ask Dr. Trout 2010. American Angler Magazine July-August issue. p. 12. Ask Dr. Trout 2010. American Angler Magazine Sept-October issue. p. 12. Ask Dr. Trout 2010. American Angler Magazine November-December issue. p. 13. PARTICIPANTS: We are currently working on a collaborative project with Dr. Troy Zorn and Andy Neufer on population regulation in Michigan brook trout TARGET AUDIENCES: Target audiences are both the scientific community and the general public. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
We are currently assessing the relative importance of density dependent and density independent factors on the rate of population change and growth for the dominant species (longnose dace, rosyside dace, mottled sculpin and rainbow trout) in the fish assemblage in Coweeta Creek from 1984-2004. We also began a study examining microhabitat use in southern brook trout that will continue through 2012. We are continuing data analysis on a comparative population dynamics study of Michigan brook trout (in collaboration with T. Zorn & A. Neufer, Michigan DNR) to determine the generality of our published results for southern brook trout. We published a paper that used modified Fourier analysis of daily average discharge data to quantify hydrologic variability for three streams and then linked measures of fish assemblage stability via multivariate autoregressive (MAR) models. The results demonstrated that the streams represent gradients in both hydrologic and fish assemblage stability. There was a positive relationship between predictability of catastrophic high and low flows and fish assemblage stability. This technique shows promise for linking hydrologic variability directly to fish assemblage stability and, more broadly, for quantifying links between flow regulation and the viability of native aquatic faunas. We published a paper using 20 years of fish abundance data combined with critical swimming velocity data to provide direct evidence that a shifting hydrodynamic barrier affects the longitudinal distribution of fishes in Coweeta Creek. We observed increased diversity in sites, produced by species immigrating upstream during periodic droughts (1985-1988, 1999-2002). Critical velocity measurements showed that residents could tolerate faster water velocities than drought immigrants and that upstream velocities in non-drought years were higher than those in several downstream sites. These data support the hypothesis that local fish diversity in this system is limited by the ability of drought immigrants to pass an upstream hydrodynamic barrier and may be a general explanation for the worldwide pattern of longitudinal diversity gradients in lotic systems. Our results highlight the relationship between natural flow variation and maintenance of local diversity and demonstrate the need for long-term ecological data. We published an additional paper demonstrating that behaviors of mottled sculpin were consistent with the expectations of Giving-Up Density theory. We found that adult mottled sculpin established territories within patches characterized by significantly higher prey densities and prey renewal rates than patches occupied by juveniles or randomly selected patches, and that patches abandoned by adult sculpin possessed significantly lower prey densities than newly occupied patches. These results provide the first evidence of the applicability of GUD theory to a stream dwelling organism, and they elucidate the underlying factors influencing juvenile and adult sculpin habitat selection and movement behaviors.

Publications

Petty, J. T. & G. D. Grossman. 2010. Giving-up densities and ideal preemptive patch use in a predatory benthic stream fish. Freshwat. Biol. 55:780-793.
Grossman, G.D., Ratajczak, R.E., Wagner, C.M., & J. T. Petty. 2010. Dynamics and population regulation of southern brook trout (Salvelinus fontinalis) in a southern Appalachian stream. Freshwat. Biol.55:1494-1508.
Grossman, G.D. & J.L. Sabo. 2010. Incorporating environmental variation into models of community stability: examples from stream fish assemblages. Community Ecology of Stream Fishes, Am. Fish. Soc. Symp. 73:407-426.
Grossman, G.D., Ratajczak, R.E., Farr, M.D. Wagner, C.M., & J. T. Petty. 2010. Why there are fewer fish upstream. Community Ecology of Stream Fishes, Am. Fish. Soc. Symp. 73:63-81.
Grossman, G.D. & J.L. Sabo. 2010. Structure and dynamics of stream fish assemblages: a commentary. Community Ecology of Stream Fishes, Am. Fish. Soc. Symp. 73:401-405.
Gotelli, N. Dorazio, R, Ellison, A. & G. D. Grossman. 2010. Detecting temporal trends in species assemblages with randomization procedures and hierarchical models. Phil. Trans. R. Soc. B. 365:3621-3631

Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: Listed below are presentations where we disseminated our research results. Scientific Presentations: Grossman, G.D. & 3 co-authors. 2009. Long-term population dynamics of a southern brook trout population. American Fisheries Society Annual Meeting, Nashville TN Grossman, G.D. & 3 co-authors. 2009. Demographic regulation of a southern brook trout population. North American Benthological Society Annual Meeting, Grand Rapids MI Grossman, G.D. 2009 Southern brook trout, habitat, population dynamics and a potential fishery. Oconee River Chapter, Trout Unlimited. Athens, GA Elkins, D. & G.D. Grossman. 2009. The effects of rainbow trout introductions on native fishes in a southern Appalachian stream. American Fisheries Society Annual Meeting, Nashville TN. This paper won an honorable mention in the student paper competition. Hazelton, P. & G.D. Grossman. 2009. Turbidity, velocity and competition affect foraging success in rosyside dace and yellowfin shiner. American Fisheries Society Annual Meeting, Nashville TN Popular Publications: Ask Dr. Trout 2009. American Angler Magazine May-June issue. p. 11. Ask Dr. Trout 2009. American Angler Magazine, July-August issue. p. 13. Ask Dr. Trout 2009. American Angler Magazine, September-October issue. p. 13. Ask Dr. Trout 2009. American Angler Magazine November-December issue. p. 9. PARTICIPANTS: We did some collaborative work with Professor Raymond P. Morgan, from the University of Maryland Center for Environmental Science, examining the genetics of brook trout in our study site. We found that at site contained pure southern brookies and they have very low average hererozygosity. We are also planning a collaborative project with Dr. Troy Zorn and Andy Neufer on Population Regulation in Michigan Brook trout (Salvelinus fontinalis) TARGET AUDIENCES: Target audiences are both the scientific community as well as the general public. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
A total of four papers in international scientific journals were published (with five more in press) in 2009. Two scientific papers were published examining the effects of turbidity, velocity, and intra- and inter-specific competition on feeding ecology of a native minnow the rosyside dace (dace) and a purportedly introduced stream minnow the yellowfin shiner (shiner). In the first paper, we found that increased turbidity and velocity produced significant decreases in the number of prey captured by dace and shiners. Results from the second paper demonstrated that dominance was positively correlated with length in intraspecific groups of both species, and dominant fish held more profitable foraging positions. Shiners were dominant more often than dace in interspecific trials. Aggression rate was best explained by models containing fish length and turbidity. These results suggest behavioural variables are as important as physical factors in determining reactive distance and capture probability by these minnows. We also conducted collaborative work with Drs. Ray Morgan, and Tim King from the University of Maryland and USGS respectively. This investigation demonstrated that the brook trout located in Upper Ball Creek are pure southern strain fish and have low average hererozygosity. We currently are examining population dynamics of a Michigan brook trout population as a comparative study to our in press publication on population regulation in southern strain brook trout. This study is a collaborative effort between our lab and Drs. Troy Zorn and Andy Neufer of Michigan DNR. Our third publication dealt with comparisons of constrained and stratified methods of assessing microhabitat availability for stream fishes. Our results suggest that either method for quantifying microhabitat availability can be used to quantify the general habitat use patterns of this species, but constrained analyses yielded a more restricted view of the total habitat available. Nonetheless, if the fishes range over a site, clearly stratified habitat availability analysis is preferred. The fourth paper published in 2009 evaluated the purported introduction of the yellowfin shiner, in the Little Tennessee River basin. We used a phylogeographic approach, examining sequence data from one mitochondrial and one nuclear locus, to determine the likely source of the population. Our results suggest that shiners have a a complex history and cannot reject the possibility this fish is native to the Little Tennessee. Results from papers in press will be presented in next year's CRIS report.

Publications

Grossman, G.D. and J. P. Skyfield, J.P. 2009. Quantifying microhabitat availability: random versus focal fish methods. Hydrobiologia 624:235-240.
Hazelton, P.B. and G.D. Grossman. 2009. Turbidity, velocity and interspecific interactions affect foraging success of rosyside dace (Clinostomus funduloides) and yellowfin shiners (Notropis lutipinnis). Ecology Freshwater Fish 18: 427- 436.
Hazelton, P.B. and G.D. Grossman. 2009. The effects of turbidity and an invasive species on foraging success of rosyside dace (Clinostomus funduloides). Freshwater Biol. 54: 1977-1989.
Scott, C.H., Cashner, M., Grossman, G.D., and J.P. Wares. 2009. An awkward introduction: phylogeography of Notropis lutipinnis in its native range and the Little Tennessee River. Ecol. Freshwat. Fish: 18- 538-547.

Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: INVITED LECTURES The importance of interactive versus individualistic processes in a southern Appalachian stream fish assemblage. Dept. Ecology and Evolutionary Biology, Tulane University, New Orleans, LA The importance of interactive versus individualistic processes in a southern Appalachian stream fish assemblage. Dept. Animal Biology, University of Lisbon, Lisbon, Portugal. The importance of interactive versus individualistic processes in a southern Appalachian stream fish assemblage. Dept. Biology, University of North Carolina, Chapel Hill, NC. PUBLIC LECTURES From tulip trees to Tricoptera to trout: how streams work in the southern Appalachians. Southeastern Chapter Conclave, Federation Fly Fishers, Calloway Gardens, GA A different view of trout: how streams work in the southern Appalachians. RabunChapter, Trout Unlimited, Clayton, GA POPULAR PUBLICATIONS Southern Gems. 2008. American Angler Magazine, March-April issue. p. 8-9. Ask Dr. Trout 2008. American Angler Magazine, November-December issue. p. 8. PARTICIPANTS: We are also planning some collaborative work with Professor Raymond P. Morgan, from the University of Maryland Center for Environmental Science, examining the genetics of brook trout in our study site. TARGET AUDIENCES: Target audiences are both the scientific community as well as the general public. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
We completed a Master's thesis on an experiment examining the effects of turbidity, velocity, and intra- and inter-specific competition on feeding ecology of a native minnow rosyside dace and a potential invasive the yellowfin shiner. Two scientific papers detailing the findings of this work have been submitted for peer reviewed publication. Multiple regression and model selection techniques (Akaike's Information Criteria) indicated that reactive distance, regardless of intra or interspecific treatment, was primarily affected by turbidity. However, capture success was more dependent on social factors including dominance and competitor presence. Our results also indicate that fish held positions farther from the substratum at higher velocities, and higher velocities were linked with increased movement rates. These shifts could subject rosyside dace and yellowfin shiners to increased focal point velocities and increased energy expenditures while foraging. Behavioral factors such as dominance affected foraging behavior and displayed interactions with physical factors. Dominant fish had higher movement rates and higher capture success than subordinate fish regardless of species. Our results suggest that controlling stream sedimentation and other aspects of habitat degradation will be necessary to maintain habitat for rosyside dace and other native species in the southern Appalachian region. We will shortly submit a manuscript examining the population dynamics of brook trout in a southern Appalachian watershed. In this study, we used information theoretic statistics (AIC) and regression analysis to assess the processes capable of explaining long-term demographic variation in a lightly exploited brook trout population in Ball Creek, NC. We sampled a 100m long 3rd order site during both spring and autumn 1991- 2004, using three pass electrofishing. Principle component analysis indicated that the site had lower average velocities, greater amounts of depositional substrata and lower amount of erosional substrata during the 1999-2002 drought than in non-drought years. In addition, drought years had lower flows and lower variation in flows than non-drought years. Both young-of- the year (YOY) and adult densities varied by an order of magnitude during the study. We detected a significant stock-recruitment relationship between both spring and autumn densities of adults in year t and autumn YOY density in year t+1. Lastly, spring YOY density was positively correlated with autumn YOY density and with spring mean YOY standard length (SL), suggesting that processes affecting recruitment show residual effects at least in the first year of life. This population appears to be regulated primarily by density dependent processes although high flows also negatively affected mean standard lengths of YOY. We are also planning some collaborative work with Professor Raymond P. Morgan, from the University of Maryland Center for Environmental Science, examining the genetics of brook trout in our study site.

Publications

Petty, J. T. and G. D. Grossman. 2007. Size-dependent territoriality of mottled sculpin in a southern Appalachian stream. Trans. Am. Fish. Soc. 136:1750-1761.
Grossman, G.D. and J. Lobon-Cervia. 2007. Where we are, where we are going... Ecol. Freshwat. Fish 16: 465-467.
DeVries D.R., Grossman, G.D., Wahl, D.H., Stone, J.A., Utter, F.M., Jennings, C.A. and D.M. Kimball. 2007. A perspective on the decision to establish an AFS marine journal. Fisheries 32(1):30.
Skyfield, J.P. and G. D. Grossman. 2008. Microhabitat use and movements of gilt darters (Percina evides) in two southeastern streams. Ecol. Freshwat. Fish 17:219-230.
Henry, B.E., and G. D. Grossman. 2008. Microhabitat use by blackbanded (Percina nigrofasciata), turquoise (Etheostoma inscriptum), and tesselated (E. olmstedi) darters during drought in a Georgia Piedmont stream. Environ. Biol. Fish. 83:171-182.
Scott, C.H., Cashner, M., Grossman, G.D., & J.P. Wares. 2008. An awkward introduction: phylogeography of Notropis lutipinnis in its 'native' range and the Little Tennessee River. Ecol. Freshwat. Fish: (in revision).
Hazelton, P.B. & G.D. Grossman. 2008. Turbidy, velocity and interspecific interactions affect foraging success of rosyside dace (Clinostomus funduloides) and yellowfin shiners (Notropis lutipinnis).Ecology Freshwater Fish: (in press).