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Analysis of Spawning Behavior, Habitat, and Season of the Federally Threatened Etheostoma scotti, Cherokee Darter (Osteichthyes: Percidae)
Casey M. Storey, Brady A. Porter, Mary C. Freeman, and Byron J. Freeman

Southeastern Naturalist, Volume 5, Number 3 (2006): 413–424

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2006 SOUTHEASTERN NATURALIST 5(3):413–424 Analysis of Spawning Behavior, Habitat, and Season of the Federally Threatened Etheostoma scotti, Cherokee Darter (Osteichthyes: Percidae) Casey M. Storey1,5,*, Brady A. Porter2, Mary C. Freeman3, and Byron J. Freeman4 Abstract - Etheostoma scotti (Cherokee darter) is a member of the subgenus Ulocentra and a federally threatened endemic to the Etowah River system, GA. Field observations of spawning behavior of the Cherokee darter were made at five stream sites to identify spawning season and habitat over two field seasons. Cherokee darters primarily spawn in pool habitats between mid-March and early June, at temperatures between 11 and 18 ºC. Egg deposition was typically on large gravel substrate, but ranged from gravel to bedrock in size and included woody debris. Spawning occurred in a variety of depths (0.09–0.59 m) and velocities (0–0.68 m/s). Introduction We examined spawning behavior and habitat of Etheostoma scotti Bauer, Etnier, and Burkhead (Cherokee darter), a federally protected species endemic to the Etowah River system in north Georgia. Described in 1995 (Bauer et al.1995) and listed as threatened in the same year (Federal Register 1994), the Cherokee darter typically inhabits small to medium-sized streams in the Piedmont physiographic province. Spawning behavior has been described for various members of the subgenus Ulocentra (sensu Bouchard 1977, Bailey and Etnier 1988), of which E. scotti is a member. This includes E. coosae (Fowler) (O’Neil 1981), E. baileyi Page and Burr, E. etnieri Bouchard (Porterfield 1998), E. flavum Etnier and Bailey (Keevin et al. 1998), E. pyrrhogaster Bailey and Etnier, E. zonistium Bailey and Etnier (Carney and Burr 1989), and E. simoterum (Cope) (Page and Mayden 1981). Typically, females attach single eggs to rock substrate in a vertical position. The size of substrate most commonly utilized by females in these descriptions is cobble or larger. This study identified spawning period and environmental variables associated with reproduction by the Cherokee darter, including substrate size for egg deposition, general habitat types (i.e., pools, runs, riffles), current velocity, and water depths. 1Institute of Ecology, University of Georgia, Athens, GA 30602-2202. 2Department of Biological Sciences, Duquesne University, Pittsburgh, PA 15282. 3US Geological Survey, Patuxent Wildlife Research Center, Athens, GA 30602. 4Georgia Museum of Natural History, Natural History Building, University of Georgia, Athens, GA 30602-1882. 5CH2M HiLL, Inc., 115 Perimeter Place, NE Suite 700, Atlanta, GA 30346. *Corresponding author - 414 Southeastern Naturalist Vol. 5, No. 3 Methods Based on sampling conducted in winter 2002 across the Cherokee darter’s range (Fig. 1), we chose the five sites where Cherokee darters were most abundant. Sites selected were Shoal Creek in Dawson County, McCanless Creek and Hickory Log Creek in Cherokee County, Butler Creek in Cobb County, and Whitehead Creek in Paulding County. The lengths of the study reaches varied from site to site depending on the densities of Cherokee darters, property boundaries, access via roads, and habitat. The reach lengths ranged from 40 m (Hickory Log Creek) to 140 m (Whitehead Creek). Species of the subgenus Ulocentra are known to begin spawning in early spring (Bauer et al. 1995, Boschung and Mayden 2004, Etnier and Starnes 1993, O’Neil 1981, Porterfield 1998, Suttkus and Etnier 1991). In an effort to record conditions driving the onset of spawning, we began observations, via snorkeling conducted by two observers, in March during base-flow conditions. Observations were made over a 2-year period during March–June. The observation period ended when spawning activity (including courting, spawning, and chasing) was no longer observed over several visits to each site, or until a majority of observed individuals no longer displayed courting behavior. In 2002, observations began on 22 March and ended on 15 May, and in 2003, field observations began on 21 March and extended to 10 June. During both years, an attempt was made to visit all five sites at regular intervals (once every three to four weeks in 2002, and once every week or two in 2003). In the Figure 1. Location of study sites in the Etowah River basin, GA. 2006 C.M. Storey, B.A. Porter, M.C. Freeman, and B.J. Freeman 415 2002 field season, a total of 27.5 hours of field observations were logged, with 13 visits made at all sites combined. Observation time in 2003 was greater, with a total of 60.6 observation hours and 36 visits. Prior to snorkel observations, water-quality parameters were measured with a Hydrolab Datasonde® 4a and a Hach Turbidimeter® model 2100P. Parameters measured included turbidity, conductivity, temperature, and pH. In addition, ONSET Optic Stowaway Temp™ temperature loggers were deployed at all sites during each year and set to record temperatures at 15- minute intervals. Reaches were snorkeled in an upstream direction. Habitats observable through a snorkel mask (depth > 0.2 m) were visually scanned for the presence of Cherokee darters. Habitat too shallow to be observed through a snorkel mask (depth < 0.2 m) was scanned from above the water surface for the presence of Cherokee darters. Cherokee darters were counted, and individuals were monitored for signs of spawning behavior. This behavior included the mounting of females by males, chasing of females by males, or pairing, in which a male and female were at rest immediately adjacent to one another on the streambed. When courting or spawning behavior was observed, pairs were followed until the activity ceased or the pair was lost. When spawning events took place, the substrate upon which the egg was attached was flagged and left in place until snorkeling of the reach was complete. After the reach was completely snorkeled, measurements were taken at all flagged spawning sites. Velocity (0.01 m/s) and depth (0.01 m) were measured at five points adjacent to the spawn site (immediately upstream, immediately downstream, adjacent right and left, and on top) with a Marsh- McBirney Inc. FLO-MATE™ portable flow meter Model 2000 mounted on a top-setting wading rod. All velocity measurements were taken at 60% depth. Depth measurements were taken in tenths of feet and later converted to meters. The dimensions of the substrate upon which the spawning took place were measured to the nearest half centimeter and classified, based on the median axis measurement, by Wentworth size category (Gordon et al. 1992). The depth of the area immediately surrounding the spawn was measured to the nearest 0.01 m. In 2003, the locations of observed spawns were plotted within each reach using temporary benchmarks. At sites where a minimum of ten spawns were observed, we measured reach-scale spawning parameters using a Leica® electronic total-station surveyor. After spawning observations were concluded for the 2003 season, we measured longitudinal variation in bed elevation and water-surface elevation along the length of the reach. Elevation measurements were taken at 0.5–2.0-m (usually 1-m) intervals along the thalweg during base-flow conditions, and were plotted to illustrate upstream to downstream variation in channel form. The bed elevations of the previously triangulated spawn localities were measured, and the results superimposed upon the graphed bed and water-surface elevations to examine occurrence of spawns relative to pool-run-riffle structure within the site. 416 Southeastern Naturalist Vol. 5, No. 3 Results Spawning acts were observed at all sites. During 2002, all observed spawns occurred from 23 April–30 April, whereas in 2003, we observed spawns from 21 March through early June (Table 1). Observations were terminated after 10 June 2003, when we observed only 15 individuals and a single spawning pair in the study reach at Hickory Log Creek (Table 1). We observed a total of 63 spawning acts during the 2-year study. Spawning occurred on a variety of substrates and at varying depths and velocities. Females most frequently selected gravel and cobble-sized rocks upon which Table 1. Recorded spawning activity of observed Etheostoma scotti at all sites (2002–2003) in Georgia Streams. Behavior: M/M = male chasing or displaying to other male, M/F =male chasing or displaying to female, PS = pseudo spawn, S = spawn, DS = dry spawn, C = courting, NSA = no spawning related activity observed. NA = not available, ± = approximation of data. Water Conductivity Turbidity Males Females Behavior temp. (ºC) (􀂗S/cm) (NTU) pH McCanless Creek 22-Mar-02 10 4 M/M 9.37 35.9 NA 7.95 23-Apr-02 NA NA M/F, M/M, S 18.09 52.0 NA 7.58 14-May-02 11 12 M/F, PS, C 16.76 51.0 NA 7.66 21-Mar-03 19 18 M/M, C 16.06 44.9 NA 7.74 29-Mar-03 9 5 PS, C 17.05 23.3 NA 7.69 1-Apr-03 20 21 M/F 9.31 24.0 3.39 7.22 13-Apr-03 19 13 S 16.09 49.0 2.78 NA 17-Apr-03 25 25 M/M, S, PS 15.01 52.0 2.55 NA 29-Apr-03 24 24 S 16.27 50.0 3.56 NA 13-May-03 19 16 M/F, S, DS, C 14.42 44.0 4.4 NA 27-May-03 13 13 NSA 17.61 47.0 NA NA Hickory Log Creek 11-Apr-02 5 6 M/M 15.22 34.0 NA 6.95 23-Apr-02 NA NA M/F, S, 14.49 35.0 NA 7.14 14-May-02 2 10 NSA 14.70 36.0 NA 7.44 21-Mar-03 35 25 S, PS, 13.60 33.5 NA 7.27 29-Mar-03 27 57 M/M, C 15.25 8.1 NA 7.12 1-Apr-03 35 56 M/M, M/F 11.71 7.0 NA 7.15 9-Apr-03 14 26 NSA 11.85 36.0 11.5 NA 17-Apr-03 17 34 C 13.90 38.0 3.83 NA 28-Apr-03 17 15 S 14.62 37.0 5.84 7.09 13-May-03 10 15 M/F 16.93 9.43 6.12 7.46 27-May-03 9 8 S 16.70 34.0 NA 7.38 10-Jun-03 8 7 M/M, S 18.10 NA 6.11 NA Shoal Creek 26-Mar-02 2 2 NSA 12.64 19.0 NA 6.8 11-Apr-02 2 2 M/F 15.22 20.1 NA 7.4 30-Apr-02 4 2 M/F, S, PS 16.50 20.0 NA 6.97 23-Mar-03 0 5 NSA 13.70 20.6 NA 7.27 1-Apr-03 8 9 NSA 14.32 NA NA 7.08 13-Apr-03 8 6 M/M, S 11.47 26.0 3.40 7.03 28-Apr-03 5 4 S 13.38 25.0 4.41 NA 13-May-03 3 3 C, M/F 13.02 19.0 5.13 7.11 27-May-03 2 4 NSA 14.63 20.0 NA 6.19 2006 C.M. Storey, B.A. Porter, M.C. Freeman, and B.J. Freeman 417 to deposit eggs. However, females used substrates varying from gravel to bedrock, as well as woody debris (Fig. 2). Velocities at spawning sites ranged from 0 to 0.68 m/s, with a mean of 0.24 m/s. Depth ranged from 0.09 to 0.59 m, with an average of 0.31 m (Fig. 3). Water characteristics varied across sites and dates (Table 1). For the dates when spawning was observed, temperatures ranged from 11.47 to 18.09 ºC, dissolved oxygen ranged from 8.84 to 11.32 mg/L, conductivity ranged from 20.1 to 113 􀂗S/cm, turbidity from 2.55 to 6.11 NTU, and pH ranged from 6.97 to 7.91. Continuous records of water temperature were obtained for comparable periods in both years at three sites, and showed that water temperatures were on average cooler during the 2003 spawning season compared to 2002 (Table 2). Differences were most pronounced early in the season. For example, at the Shoal Creek site (which had the most complete Table 1, continued. Water Conductivity Turbidity Males Females Behavior temp. (ºC) (􀂗S/cm) (NTU) pH Butler Creek 4-Apr-02 1 3 NSA 14.56 78.0 NA 7.54 25-Apr-02 8 6 C, S, PS 16.90 89.0 NA 7.16 15-May-02 13 18 M/F, MM 14.23 100.0 NA 7.47 25-Mar-03 17 21 S, PS 13.52 109.0 NA 7.91 31-Mar-03 6± 8± C, PS, M/F 11.12 95.2 3.54 7.19 4-Apr-03 21 18 M/F, S, PS 16.80 106.0 4.5 7.45 15-Apr-03 23 25 C, MF 16.77 113.0 2.7 NA 12-May-03 11 18 S, PS, DS 16.45 113.0 NA 7.47 30-May-03 14 8 M/F 15.95 110.0 NA 7.22 Whitehead Creek 4-Apr-02 3 2 M/M 12.94 34.0 NA NA 18-Apr-02 5 10 NSA 19.75 47.0 NA 7.36 25-Apr-02 5 6 M/M, C 18.92 10.0 NA 7.39 15-May-02 8 17 C, PS 16.51 47.0 NA 7.53 26-Mar-03 17 17 C, PS 17.08 41.1 NA 7.66 31-Mar-03 6 8 NSA 8.91 18.3 4.38 6.92 4-Apr-03 10 14 C, PS 14.59 45.0 3.4 7.37 15-Apr-03 10 14 C, S 14.05 46.0 3.01 NA 29-Apr-03 3± 8± NSA 18.32 47.0 NA 7.41 12-May-03 9 7 C 18.77 41.0 NA 7.3 30-May-03 7 2 NSA 17.10 41.0 NA 7.11 Table 2. Temperature data for three Etheostoma scotti study sites in Georgia streams, comparing average daily temperature and total degree days (summed daily averages for dates included) between 2002 and 2003. Shoal Creek Whitehead Creek Hickory Log Creek 27 March–26 May 5 April–29 May 11 April–26 May Year 2002 2003 2002 2003 2002 2003 Average daily temp. (oC) 15.1 14.7 16.7 15.7 16.5 15.9 Total degree days 924 827 918 861 757 730 418 Southeastern Naturalist Vol. 5, No. 3 Figure 2. Spawning substrate utilization by Etheostoma scotti across all localities in the Etowah River basin, GA, observed through seasons 2002 and 2003. Substrate types follow Wentworth size scale (Gordon et al. 1992). The y-axis shows the substrate selection frequency. Figure 3. Plot of depths and velocities at observed Etheostoma scotti spawns for all sites in the Etowah River basin, GA, 2002 and 2003. Large squares = McCanless Creek, small squares = Hickory Log Creek, open circles = Whitehead Creek, closed circles = Shoal Creek, triangles = Butler Creek. 2006 C.M. Storey, B.A. Porter, M.C. Freeman, and B.J. Freeman 419 temperature record), daily temperatures during April averaged 15.3 in 2002 compared to 13.7 in 2003. During spawning observation, male Cherokee darters were often observed displaying perpendicular to the long axis of females, with dorsal fins erect and nuptial colors at high intensity. Males often pursued receptive females, mounting them and periodically pecking at their nape to instigate spawning behavior. Females moved about scanning substrate in what appeared to be an attempt to select a suitable egg-deposition point. Often, females would peck substrate, possibly attempting to signify to the male her readiness to spawn. This pecking often elicited quivering by the male as he mounted or positioned himself parallel to the female. Then the female continued moving about in search of further appropriate egg-deposition points, with the male matching her movements. Once suitable substrate was found, the female would again peck at a spot, usually on the vertical surface of the substrate, and the male would begin to quiver and release milt. Very soon after pecking, and while the male was still quivering, the female would quiver briefly and quickly move forward with her ovipositor touching the exact point that she pecked. After this series of events, a slightly opaque and colorless egg could be seen attached within small dimples or fissures upon the substrate selected. We observed multiple spawning acts on a single rock only once. Females appeared to select substrate free of algal growth or sediment coatings. In many situations, females would remove fine debris or algae by pecking the substrate, frequently several times. This was most often noted in streams or reaches with dense algal growth. In many instances, when frequent pecks were made, the female would abandon the site and continue the search for suitable substrate. Occasionally, a female would select/peck a substrate and the male would begin to quiver; but, instead of placing her ovipositor over the cleaned crevice, the female would abruptly change positions or move off the substrate and continue to search. We termed this behavior pseudospawning. The observation of a pseudo-spawn indicated that spawning was taking place on the date of the observation (Table 1). This was useful in determining the duration of spawning and in signifying spawning pairs that should be observed. Towards the end of the spawning season we observed “dry spawning.” In this situation, the entire courting and spawning ritual would be carried out by a pair, but after positioning of the ovipositor by the female, an egg would not be observed in the spot. This behavior was noted at McCanless Creek (13 May, 2003) and Butler Creek (12 May, 2003) and we treated it as a true spawn, taking measurements as outlined in the methods. At the conclusion of the snorkel observations, McCanless Creek and Butler Creek were selected for longitudinal mapping, because 10 or more spawns were observed in these creeks. Observed spawns plotted against the longitudinal variation in bed and water-surface elevation indicated that 420 Southeastern Naturalist Vol. 5, No. 3 Figure 4. Total-station analysis of water-surface elevation (upper line), bed elevation (lower line), plotted downstream (0 m) to upstream for the Butler Creek study site in the Etowah River basin, GA, shown with habitat types. Etheostoma scotti spawning locations and elevations are indicated by shaded circles; locations shown above or below the bed are lateral to the thalweg. Figure 5. Total-station analysis of water-surface elevation (upper line) and bed elevation (lower line), plotted downstream (0 m) to upstream for the McCanless Creek study site in the Etowah River basin, GA, shown with habitat types. Etheostoma scotti spawning locations and elevations are indicated by shaded circles; locations shown above or below the bed are lateral to the thalweg. 2006 C.M. Storey, B.A. Porter, M.C. Freeman, and B.J. Freeman 421 spawning was most concentrated in topographic valleys (Figs. 4 and 5). Despite the availability of riffles throughout the studied reaches, the selected spawning habitat was consistently located at the margins, heads, or tails of pools, as well as in run habitat. Discussion Field observations correspond with laboratory observations of Cherokee darters spawning (Bauer et al. 1995); for example, females were observed “visually scrutinizing” their surroundings, presumably in search of appropriate spawning substrata. Additionally, in the laboratory and in the field, male Cherokee darters tend to maintain a “roving territory” around the female with which they are courting. As the female may travel several meters or more through a variety of habitats, the male maintains a territorial area. When other males enter this loosely defined territory, the male will often give chase. In this process, he may lose track of the female or have another male take his place. Cherokee darters appear to have a potentially prolonged spawning period, extending from at least the middle of March to early June, corresponding to water temperatures of 11.5 to 18.1 ºC. The extended spawning season observed in 2003 (in contrast to 2002) may have been related to cooler temperatures. Indeed, temperature has been cited as a major factor contributing to the length of spawning season in percids (Hubbs 1985). In addition, we hypothesize that cooler temperatures in 2003 may have been responsible for the observed “dry spawn” behavior noted near the end of the spawning period, if appropriate water temperatures stimulate spawning behavior despite the inability of females to deposit or produce additional eggs. Spawning sites characteristically occurred in run and pool habitats, with moderate depths and velocities (i.e., usually < 0.5 m and < 0.4 m/s, respectively), and most often, on gravel-sized sediment. The use of gravel for egg attachment contrasts with the use of cobble and boulder substrates frequently reported for other Ulocentra species (Porterfield 1998), but Cherokee darters also utilized a variety of bed sediments, from medium gravel to bedrock. Woody debris was also used. Other Ulocentra also peck substrate prior to egg placement (Porterfield 1998). After observing numerous spawning Cherokee darters, we propose that this behavior probably serves two purposes. The first is to stimulate the male and to signal the onset of egg deposition. Secondly, this behavior may clear each site for strong adherence of the individual egg. Thus, availability of bed sediments that are relatively free of fine sediment and algal growth may affect habitat suitability for spawning. Future research into a relationship between the pecking behavior and periphyton density could be helpful in determining to what extent nutrient loading and algal growth may limit spawning habitat. Such an analysis could 422 Southeastern Naturalist Vol. 5, No. 3 offer an explanation for pecking behavior beyond its use in courtship rituals. If this behavior varies among Ulocentra species, then this variation could predict differences in population responses to stream eutrophication. Our observations on habitat use and spawning period provide information that should be useful for avoiding development-related impacts on Cherokee darters. Urbanization frequently leads to a loss of stream fish species (Walters et al., in press; Wang et al. 2001). Habitat alteration relative to requirements for reproduction may contribute to these losses. From our field observations, it is clear that a reduction in the availability of gravel and cobble substrate from sedimentation could reduce the spawning success of the Cherokee darter. Excessive sediment inputs can additionally cause infilling of pools (the primary sites of spawning) and alteration of depth and velocity regimes (Berkman and Rabeni 1987, Waters 1995). Lower Cherokee darter abundances have been associated with increasing levels of fine sediments and higher bed mobility (Roy 2004), possibly reflecting lower reproductive success and demonstrating the importance of erosion and sedimentation controls. Roy (2004) also related lower Cherokee darter abundances to increased magnitude and flashiness of stormflows, which is in turn related to increased urban and impervious land cover. Increasing runoff from impervious surfaces and loss of riparian buffers may also increase stream temperatures (Barton et al. 1985, Osborne and Kovacic 1993, Poole and Berman 2001), adversely affecting Cherokee darter reproduction. We observed spawning to occur across a temperature range of 11.0–18.1 ºC. While this range is relatively large, the protection of forested riparian buffers is suggested throughout the range of this species in order to prevent the early elevation of temperatures that could shorten the spawning season. Finally, culvert installation and other types of urban and suburban development that cause instream disturbance could be timed to avoid disturbing spawning and incubation of eggs. Conservatively, restricting instream disturbance during a period spanning March to early June should benefit Cherokee darter reproduction. Acknowledgments We thank Megan Hagler, Jane Rogers, Ryan Creehan, and Jesslyn Shields for their assistance in various aspects of this project. We especially thank property owners that granted access to our snorkel sites through both field seasons. This research was funded by the US Department of the Interior through Cooperative Agreement No. 1434-HQ-97-RU-01551 Research Work Order 66. Literature Cited Bailey, R.M., and D.A. Etnier. 1988. Comments on the subgenera of darters (Percidae) with descriptions of two new species of Etheostoma (Ulocentra) from southeastern United States. Miscellaneous Publications of the Museum of Zoology University of Michigan 175:1–48 2006 C.M. Storey, B.A. Porter, M.C. Freeman, and B.J. Freeman 423 Barton, D.R., W.D. Taylor, and R.M. Biette. 1985. Dimensions of riparian buffer strips required to maintain trout habitat in southern Ontario streams. North American Journal of Fisheries Management 5:364–378. Bauer, B.H., D.A. Etnier, and N.M. Burkhead. 1995. Etheostoma (Ulocentra) scotti (Osteichthyes: Percidae), a new darter from the Etowah River system in Georgia. Bulletin of the Alabama Museum of Natural History 17:1–16. Berkman, H.E., and C.F. Rabeni. 1987. Effect of siltation on stream fish communities. Environmental Biology of Fishes 18:285–294. Boschung, H.T., and R.L. Mayden. 2004. Fishes of Alabama. Smithsonian Books, Washington, DC. 736 pp. Bouchard, R.W. 1977. Etheostoma etnieri, a new percid fish from the Caney Fork (Cumberland) River system, Tennessee, with a redescription of the subgenus Ulocentra. Tulane Studies in Zoology and Botany 19:105–130. Carney, D.A., and B.M. Burr. 1989. Life histories of the bandfin darter, Etheostoma zonistium, and the firebelly darter, Etheostoma pyrrhogaster, in western Kentucky. Illinois Natural History Survey Biological Notes 134:1–16. Etnier, D.A., and W.C. Starnes. 1993. The Fishes of Tennessee. University of Tennessee Press, Knoxville, TN. 681 pp. Federal Register. 1994. Endangered and threatened wildlife and plants: Determination of threatened status for the Cherokee darter and endangered status for the Etowah darter. US Federal Register 59 (243):65505–53702. Gordon, N.D., T.A. McMahon, and B.L. Finlayson. 1992. Stream Hydrology: An Introduction for Ecologists. John Wiley and Sons. Chichester, UK. 526 pp. Hubbs, C. 1985. Darter reproductive seasons. Copeia 1985:56–58. Keevin, T.M., L.M. Page, and C.E. Johnston. 1998. The spawning behavior of the saffron darter (Etheostoma flavum). Transactions Kentucky Academy of Science 50:55–58. O’Neil, P.E. 1981. Life history of Etheostoma coosae (Pisces: Percidae) in Barbaree Creek, Alabama. Tulane Studies in Zoology and Botany 23:75–83. Osborne, L.L., and D.A. Kovacic. 1993. Riparian vegetated buffer strips in waterquality restoration and stream management. Freshwater Biology 29:243–258. Page, L.M., and R.L. Mayden. 1981. The life history of the Tennessee snubnose darter, Etheostoma simoterum in Brush Creek, Tennessee. Illinois Natural History Survey Biological Notes 117:1–11. Porterfield, J.C. 1998. Spawning behavior of snubnose darters (Percidae) in natural and laboratory environments. Environmental Biology of Fishes 53:413–419. Poole, G.C., and C.H. Berman. 2001. An ecological perspective on in-stream temperature: Natural heat dynamics and mechanisms of human-caused thermal degradation. Environmental Management 27:787–802. Roy, A.H. 2004. Can riparian forests mediate impacts of urbanization on stream fish assemblages? PhD. Dissertation. University of Georgia, Athens, GA. Suttkus, R.D., and D.A. Etnier. 1991. Etheostoma tallapoosae and E. brevirostrum, two new darters, subgenus Ulocentra, from the Alabama River drainage. Tulane Studies in Zoology and Botany 28(1):1–24. Wang, L.Z., J. Lyons, and P. Kanehl. 2001. Impacts of urbanization on stream habitat and fish across multiple spatial scales. Environmental Management 28:255–266. 424 Southeastern Naturalist Vol. 5, No. 3 Walters, D.M., M.C. Freeman, D.S. Leigh, B.J. Freeman, and C.M. Pringle. In press. Urbanization effects on fishes and habitat quality in a southern Piedmont river basin. In L.R. Brown, R.M. Hughes, R. Gray, and M.R. Meador (Eds.). Effects of Urbanization of Stream Ecosystems, American Fisheries Society Symposium 47. Bethesda, MD. Waters, T.F. 1995. Sediment in streams: Sources, biological effects, and control. American Fisheries Society Monograph 7. Bethesda, MD.