Regular issues
Monographs
Special Issues



Southeastern Naturalist
    SENA Home
    Range and Scope
    Board of Editors
    Staff
    Editorial Workflow
    Publication Charges
    Subscriptions

Other EH Journals
    Northeastern Naturalist
    Caribbean Naturalist
    Neotropical Naturalist
    Urban Naturalist
    Eastern Paleontologist
    Journal of the North Atlantic
    Eastern Biologist

EH Natural History Home

Movement, Homing, and Fates of Fluvial-Specialist Shoal Bass Following Translocation into an Impoundment
Andrew T. Taylor and Douglas L. Peterson

Southeastern Naturalist, Volume 14, Issue 3 (2015): 425–437

Full-text pdf (Accessible only to subscribers.To subscribe click here.)

 

Site by Bennett Web & Design Co.
Southeastern Naturalist 425 A.T. Taylor and D.L. Peterson 22001155 SOUTHEASTERN NATURALIST 1V4o(3l.) :1442,5 N–4o3. 73 Movement, Homing, and Fates of Fluvial-Specialist Shoal Bass Following Translocation into an Impoundment Andrew T. Taylor1 and Douglas L. Peterson1,* Abstract - Micropterus cataractae (Shoal Bass), an enigmatic fluvial specialist, has experienced range-wide declines because of habitat fragmentation and other negative effects of impounded rivers. In addition to these concerns, anglers often translocate Shoal Bass from riverine habitats to impoundments following tournament weigh-ins. To investigate the potential effects of this practice, we translocated adult Shoal Bass from riverine habitats to a downstream impoundment and assessed their movements, homing abilities, and eventual fates. All fish rapidly evacuated the impoundment in favor of lotic habitats, and the majority of translocated fish returned upstream within about 3 weeks. Half of our translocated fish also displayed homing to within 1 river km of their original capture site. Our results demonstrate that fluvial-specialist Shoal Bass can survive translocation into impoundments, but the differential effects of translocation associated with fishing tournaments should also be considered in the management of Shoal Bass fisheries. Introduction Fluvial-specialist fishes—species that require lotic habitats for at least a portion of their life cycles—are a diverse group that faces a suite of conservation challenges. In the US, this group encompasses many native cyprinids, catostomids, percids, and other taxa. Fluvial-specialist fishes feature a diverse array of adaptations to dynamic lotic habitats, including various reproductive strategies, feeding guilds, and morphologies (Bunn and Arthington 2002). Despite this diversity in life-history strategies, fluvial-specialist species often become imperiled because of the specificity of their habitat requirements (Moyle and Leidy 1992). The rapid loss of aquatic biodiversity in North America, including freshwater fishes, is largely attributable to the widespread alteration of fluvial habitats (Postel and Ricther 2003, Ricciardi and Rasmussen 2001), which significantly complicates conservation of fluvial fishes. Impounded river systems pose a variety of challenges to the conservation of fluvial-specialist fishes. Downstream of dams, fluvial fishes and other sensitive taxa are often unable to adapt to altered flow regimes (Poff and Zimmerman 2010), increased water withdrawals (Freeman and Marcinek 2006), and altered temperature regimes (Olden and Naiman 2009, Quinn and Kwak 2003). Upstream, impoundments transform fluvial habitats into lentic habitats that may be unsuitable for fluvial-specialist species. Impounded river systems also fragment fluvial-fish populations. Dams typically impose 2 specific types of barriers to fluvial-fish migration. The most obvious of these is the physical barrier that dams impose on upstream and downstream movement. Although downstream migration through spillways 1Warnell School of Forestry and Natural Resources, University of Georgia, 180 East Green Street, Athens, GA 30602. *Corresponding author - dpeterson@warnell.uga.edu. Manuscript Editor: Jennifer Rehage Southeastern Naturalist A.T. Taylor and D.L. Peterson 2015 Vol. 14, No. 3 426 (Schilt 2007) or hydroelectric turbines is sometimes possible, both pathways can cause mortality (Coutant and Whitney 2000). In the upstream direction, dams often create a completely impassable barrier unless fish ladders or another functional fish-passage system is provided (Porto et al. 1999, Schilt 2007). Populations in tributaries upstream from impoundments may experience an additional ecological barrier to downstream or between-tributary migration created by large expanses of unsuitable lentic habitat (sensu Pringle 1997). Impounded waters have been shown to severely hinder gene flow among populations of fluvial fishes inhabiting impoundment tributaries (Fluker et al. 2014, Herbert et al. 2003, Schwemm 2013). Micropterus cataractae Williams & Burgess (Shoal Bass) is a fluvial-specialist black bass species endemic to a heavily impounded river system. Shoal Bass are native to the Apalachicola-Chattahoochee-Flint (ACF) Basin and are described as fluvial, shoal-habitat specialists that are rarely observed in impoundments (Taylor and Peterson 2014, Williams and Burgess 1999). Shoal Bass have declined throughout much of their range primarily because of the negative effects of extensive damming within the ACF Basin (Williams and Burgess 1999). Although Shoal Bass are known to migrate distances greater than 200 km for spawning (Sammons and Goclowski 2012), most populations appear to be fragmented. In a genetic investigation of Shoal Bass in the upper Chattahoochee River Basin, mainstem dams were found to limit genetic exchange in the downstream direction while completely eliminating genetic exchange in the upstream direction (Dakin et al. 2007). These findings suggest that the long-term effects of habitat fragmentation could seriously alter population genetic structure; however, a better understanding of spawning habits, including any potential migration patterns, homing abilities, and/or spawning-site fidelities, is needed to fully understand the potential effects of fragmentation. Despite being a relatively rare fluvial-specialist species, Shoal Bass are also a popular sportfish. Shoal Bass attain relatively large sizes (up to 3990 g; International Game Fish Association 2014) and support popular tournament and non-tournament recreational and fisheries throughout much of their current range. Tournament anglers on the Flint River system of Georgia typically target M. salmoides (Lacepède) (Largemouth Bass) and Shoal Bass; participants often weigh in a mixed bag of both species (A.T. Taylor, pers. observ.). Tournament fish must be released alive after weigh-in, usually at boat ramps on the large impoundments where tournaments are held. This practice results in the translocation of Shoal Bass from fluvial habitats in the Flint River to downstream impoundments (see Ingram et al. 2013, Taylor 2012). Translocating Shoal Bass into impoundments has prompted concern from both anglers and resource managers (T. Ingram, Georgia Department of Natural Resources, Albany, GA, pers. comm.) because the practice poses a potential threat to a species that has declined throughout much of its native range (Taylor and Peterson 2014, Williams and Burgess 1999). To investigate how Shoal Bass respond to translocation into an impoundment, we conducted a telemetry experiment on the Flint River, GA, with the following objectives: 1) determine the prevalence of adult fish that return to riverine habitats Southeastern Naturalist 427 A.T. Taylor and D.L. Peterson 2015 Vol. 14, No. 3 after translocation to a downstream impoundment, 2) describe spatial and temporal movement patterns of fish following translocation, and 3) identify the eventual fate of each telemetered fish. Addressing these gaps in the current understanding of Shoal Bass ecology and biology will better inform future management and conservation efforts for Shoal Bass, and potentially, other fluvial-specialist fishes. Methods Field site description Located in southwestern Georgia within the Southeastern Plains ecoregion, the lower Flint River is characterized by limestone-bedrock outcrops, shoal complexes, and influence from spring outflows. Our study area encompassed 50 river kilometers (rkm) on the mainstem lower Flint River between Lake Blackshear and Lake Worth (Fig. 1). Unlike free-flowing reaches upstream, this portion of the lower Flint River is influenced by 2 mainstem hydroelectric dams. Crisp County Dam (CCD) forms Lake Blackshear and is operated by Crisp County Power Commission (Cordele, GA). Approximately 50 rkm downstream, the Georgia Power Dam (GPD) is operated by Georgia Power (Atlanta, GA) and forms the 6-km2 Lake Worth. In addition to the mainstem river between the 2 impoundments, our study area also included the entirety of Lake Worth. Telemetry To assess movement, homing ability, and eventual fates of Shoal Bass translocated from upstream fluvial habitats to Lake Worth, we surgically implanted radio transmitters into the body cavities of 12 adult fish captured at 3 distinct sites within the free-flowing portion of the study area (Fig. 1). We collected fish by using a boat-mounted, pulsed-DC electrofishing unit (7.5 Generator Powered Pulsator [GPP], Smith-Root, Inc., Vancouver, WA) and recorded each capture location with a handheld GPS unit. We held the captured fish in an aerated livewell while we collected additional fish at each sampling site. At the conclusion of sampling at each site, we surgically implanted an (ATS) F1840 or F1850 radio transmitter (Advanced Telemetry Systems, Isanti, MN) into the body cavity of each fish using procedures similar to Maceina et al. (1999). Transmitters had a minimum warrantied life of 333 d, weighed 20–25 g, and comprised no more than ~2% of each fish’s body weight, which minimized the likelihood that movement and behavior of telemetered fish was affected by the additional weight of the transmitter (Winter 1996). Following the surgical procedure, we allowed fish to recover in the livewell for ~30 min, during which time we transported them downstream to the release site at Cromartie Landing in Lake Worth. The total handling time from initial capture to eventual release was less than 2 hours for all fish. We used a small boat equipped with a portable receiver (ATS R2000) and a handheld directional antenna to locate transmittered fish approximately once per week from 17 February 2011 to 2 June 2011 (105 d). We recorded GPS coordinates and water temperature and depth and described the visible habitat whenever we located a tagged fish. We also employed a stationary receiver (ATS R4500SD) positioned Southeastern Naturalist A.T. Taylor and D.L. Peterson 2015 Vol. 14, No. 3 428 at the first shoal upstream of Lake Worth (~16 rkm upstream from Cromartie Landing) to determine how long it took each fish to return to the river. The range of the stationary receiver was more than double the width of the river; thus, we used the Figure 1. A map of the study area that spanned of 50 rkm of the lower Flint River, GA, from the base of Crisp County Dam (CCD) downstream to the Georgia Power Dam (GPD) that forms Lake Worth. Circled areas indicate capture sites of transmittered and translocated Shoal Bass. Southeastern Naturalist 429 A.T. Taylor and D.L. Peterson 2015 Vol. 14, No. 3 highest signal-strength recorded to approximate the time at which a telemetered fish passed the receiver. We performed 1 final active-tracking survey of the study area at the end of July 2011, separate from the weekly movement surveys, to determine the eventual fate of each tagged fish. At the conclusion of the study, we calculated daily movement rates of each fish by dividing the minimum distance moved (m) between relocations by the amount of time (d) elapsed during the relocation interval (Colle et al. 1989, Wilkerson and Fisher 1997). We determined distance traveled between each subsequent relocation event with the path tool within Google Earth version 7.1 (Google 2013), and assumed paths between points followed the main river channel. We classified Shoal Bass as having returned to their original capture site if we documented them within 1 rkm of that area and they remained there for 3 or more consecutive relocation events. We determined these criteria for homing post hoc based on an abrupt difference in the movement patterns of fish that never returned to their original capture site compared to those that did. If we did not detect fish within the study area for more than 2 consecutive weeks, we expanded our search to the first 2 rkm of river below Lake Worth and GPD. Any fish that remained completely stationary for 3 or more consecutive weekly relocation events, and was also relocated in the same location during the final tracking survey at the end of July 2011, was presumed dead and subsequently removed from movement analyses after the first relocation date on which we observed no movement. Although turbidity in our study area precluded tag recovery or visual confirmation of mortality, we reasoned that a month or more of subsequent relocations with no detectable movement was adequate to infer mortality in Shoal Bass, which is a mobile species. Hightower et al. (2001) used a similar methodology to infer mortality in Morone saxatilis Walbaum (Striped Bass). Results In total, we sampled, tagged, and translocated 12 adult Shoal Bass to Lake Worth. On 16 February 2011, we translocated 3 fish from Abrams Shoals and 6 fish from Philema Shoals (Fig. 1). The following day, we translocated 3 fish from the area just downstream of CCD. Mean body weight of translocated fish (prior to surgical implantation of transmitters) was 1267 g (range = 825–1903 g); mean total length (TL) was 414 mm (range = 367–480 mm) (Table 1). Following translocation into Lake Worth, 10 of 12 (83%) Shoal Bass eventually returned to fluvial habitats upstream of the impoundment. We later found alive the 2 fish that did not return to fluvial habitats upstream in fluvial habitats downstream of GPD. The 10 fish that returned to the river took an average of 21 d (range = 12–35 d) to traverse the 16 rkm between Cromartie Landing and the first shoal habitat upstream of Lake Worth. Fish generally proceeded upstream after reentering fluvial habitats; 1 fish paused near the stationary receiver before moving farther upstream towards its original capture site. Movement rates of translocated fish were variable, and fish size did not appear to af fect movement pattern. Translocated Shoal Bass appeared to experience 3 general phases of movement after their release in Lake Worth: river re-entry, spawning season, and reduced Southeastern Naturalist A.T. Taylor and D.L. Peterson 2015 Vol. 14, No. 3 430 summer discharge (Fig. 2). Following translocation, fish moved sporadically in Lake Worth for a few weeks before beginning to move upstream within the river channel. Average daily-movement rates peaked at 23 d post-translocation (early March), with fish averaging 955 m/d (range = 16–1784 m/d) as 10 of 12 telemetered fish returned upstream to fluvial habitats (Table 2). After returning to the river, movement rates appeared to vary with the spawning season. Between 35 and 72 d post-translocation (late March to early May 2011), we observed other adult Shoal Bass sampled in the study area to be in spawning condition (Taylor 2012), and water temperatures at that time (16–23 °C) were conducive to spawning in this species (Hurst 1969, Wright 1967). Near the middle of spawning season, movement rates of telemetered Shoal Bass decreased noticeably, averaging 160 m/d (range = 19–434 m/d; Fig. 2). Also during this period, 7 telemetered fish remained in or near Philema Shoals, the largest shoal complex in the study area. Between 72 and 106 d post-translocation (early May through early June 2011), other Shoal Bass sampled in the study area were no longer in spawning condition (Taylor 2012) and river discharge dropped by ~85 cubic meters per second (cms; Fig. 2). During this time, telemetered Shoal Bass had much lower averagemovement rates of ~20 m/d, and the majority of transmittered fish moved slightly downstream to deeper areas within the shoals (Table 2). Half (6 of 12) of the translocated Shoal Bass returned to within 1 rkm of their capture location, each remaining there for at least 3 weeks during our study (Table 1). Two of 3 Shoal Bass displaced from Abrams Shoals returned back to their capture area within 3 weeks, and thereafter, we regularly located them in close proximity to that shoal. Of the 6 fish displaced from Philema Shoals, 4 returned to Table 1. Capture location, total length (TL), weight, time required to re-enter the first shoal habitat upstream of Lake Worth (time [days]; see Fig. 1), number of relocations after initial translocation (#), overall average-movement rate (avg rate [m/day]), whether each fish homed to its original capture site, and eventual fate of each telemetered fish translocated from the lower Flint River, GA. * indicates that fish left study area after several weeks in Lake Worth and never re-entered the shoal habitats upstream of Lake Worth from where they were displaced. These fish were later discovered alive downstream of the Georgia Power Dam (GPD) and Lake Worth. ** indicates fish returned upstream to the river following translocation into Lake Worth, but were translocated a second time by tournament anglers in June 2011. Both fish were later presumed dead near Cromartie Landing. Tag # Capture area TL (mm) Weight(g) Time # Avg rate Homing? Eventual fate 701 Philema 386 1003 12 9 132 Yes Alive 711 Philema 410 1174 17 11 74 Yes Alive 721 Below CCD 457 1743 14 9 227 No Alive 731 Philema 385 906 35 10 309 No Dead** 741 Abrams 376 825 20 13 216 Yes Alive 751 Abrams 390 1092 19 10 375 Yes Alive 761 Below CCD 458 1753 21 13 643 No Dead 771 Philema 407 1185 15 11 306 Yes Alive 781 Below CCD 367 962 33 11 318 No Dead** 791 Abrams 376 838 * 4 102 No Left 820 Philema 480 1903 22 10 375 Yes Alive 931 Philema 475 1821 * 2 111 No Left Southeastern Naturalist 431 A.T. Taylor and D.L. Peterson 2015 Vol. 14, No. 3 this area and rarely ventured away. The first of these returned to Philema Shoals within 3 weeks; however, the other 3 took approximately 5–6 weeks. In contrast, the 3 Shoal Bass displaced from below CCD did not return to their capture sites. One fish from below CCD had the highest overall average-movement rate (643 m/d; Table 1) as it moved sporadically between the stationary receiver and to within 12 rkm of its capture location. Two others moved as far upstream as Philema Shoals and eventually situated themselves in smaller shoal areas between Philema and Abrams shoals. Eventual fates revealed that 5 of 12 (42%) telemetered fish had left the population or were dead at the end of our study (Table 1). One fish from Abrams Figure 2. Minimum, average, and maximum observed-movement rates in meters per day (m/d) of telemetered adult Shoal Bass following translocation into Lake Worth (primary yaxis) along with average daily discharge in cubic meters per second (cms) of the lower Flint River at USGS stream gage 02350512 at Hwy 32 bridge near Philema Shoals (secondary y-axis). Note the timing of biologically relevant events during the movement study: re-entry to river, spawning period, and reduced summer dischar ge. Southeastern Naturalist A.T. Taylor and D.L. Peterson 2015 Vol. 14, No. 3 432 Shoals and another from Philema Shoals left the study area within 1 month after translocation into Lake Worth, and we later found both alive downstream of GPD. Near the end of our study, 1 fish that had returned to the river was presumed dead after we observed no movement over consecutive relocation events from late April through the end of the movement study in June. The July survey to confirm fish fates corroborated this conclusion, because we observed no discernable fish movement. Interestingly, 2 fish that had returned to the river were eventually presumed dead near Cromartie Landing following a second translocation into Lake Worth by tournament anglers in June 2011. One of these fish was discovered in early June near the dock at Cromartie Landing the morning after a fishing tournament; the other was observed being released following a tournament weigh-in at Cromartie Landing in mid June (see Taylor 2012). We relocated both of these telemetered fish at the dock on a weekly basis until the end of July with no discernable movement. The second translocation of these fish by tournament anglers occurred after our movement study was completed; thus, these angler-induced movements did not influence the results of our movement analyses. Discussion Our study provided a direct test of Shoal Bass responses to translocation downstream into an impoundment. Our results showed that all adult Shoal Bass translocated into Lake Worth vacated the impoundment within 2–4 weeks, even though 2 fish left the study area to do so. In fact, the highest movement rates were observed as 10 of 12 Shoal Bass left the impoundment and re-entered upstream, Table 2. Telemetry data summarized by observation date for 12 adult Shoal Bass that were captured from 3 areas of the lower Flint River, GA, and translocated into Lake Worth in early February 2011. Number = number of individual fish located, time = time since translocation (days), interval = interval between observation dates (days), and percentage = % of fish moving upstream (+) and downstream (-) Mean movement rates Date Number Time Interval (min-max) during interval (m/d) Percentage 24 Feb 11 7–8 7–8* 150 (66–327) +81.8, -18.2 3 Mar 11 14–15 7 592 (22–1949) +54.5, -45.5 11 Mar 7 22–23 8 955 (16–1784) +71.4, -28.6 16 Mar 7 27–28 5 878 (44–2489) +85.7, -14.3 23 Mar 10 34–35 7 730 (64–2072) +90.0, -10.0 1 Apr 10 43–44 9 256 (19–1258) +60.0, -40.0 7 Apr 10 49–50 6 242 (5–1513) +60.0, -40.0 15 Apr 9 57–58 8 160 (19–434) +66.7, -33.3 20 Apr 8 62–63 5 181 (17–559) +62.5, -37.5 29 Apr 9 71–72 9 106 (0–562) +44.4, -44.4 18 May 8 90–91 19 23 (1–45) +12.5, -87.5 26 May 7 98–99 8 23 (0–50) +14.3, -71.4 2 Jun 6 105–106 7 20 (1–83) +33.3, -50.0 *7 days for the fish translocated on 17 February 2011 from Philema and Abrams shoals and 8 days for fish translocated on 16 February 2011 from the area just downstream of Crisp County Dam (CCD). Southeastern Naturalist 433 A.T. Taylor and D.L. Peterson 2015 Vol. 14, No. 3 fluvial habitats. The return of 6 of 12 Shoal Bass back to where they were sampled illustrated a previously unreported homing ability in the species. Our results also demonstrate that adult Shoal Bass are capable of surviving translocation to a lentic environment; however, the effects of angling and other sublethal effects of translocation should also be considered when managing Shoal Bass fisher ies. Following translocation into lentic habitats, all 12 Shoal Bass displayed a rapid evacuation of lentic habitats, the motivation for which is currently unclear. Despite subsets of translocated fish moving both upstream (10) and downstream (2) of the translocation impoundment, all 12 eventually returned to lotic habitats within several weeks of their translocation. The rapid evacuation from the impoundment suggested that fish were avoiding lentic habitats, which supports reports that Shoal Bass are rarely encountered in impoundments (Williams and Burgess 1999). Alternatively, fish could have simply been moving to shoal habitats for the imminent onset of the spawning season. Future studies are needed to evaluate the seasonal movements of Shoal Bass translocated into impoundments to better understand the factors that motivate their movements. Once adult Shoal Bass returned to fluvial habitats, their movements during the spawning season illustrated several adaptations typical of other fluvial-specialist fishes. The pattern of movements observed during the spawning season (Fig. 2) was consistent with Wright’s (1967) hypothesis that, like many other fluvial fish - es, Shoal Bass spawn during discharge pulses in the spring months (e.g., Taylor and Miller 1990, Tyus and Karp 1990). Our results also emphasize the importance of large shoal-complexes for Shoal Bass spawning (Goclowski et al. 2013, Taylor and Peterson 2014) because the majority of transmittered fish spent much of the spawning season in the largest available shoal complexes previously identified as likely spawning areas (Taylor 2012). Spawning aggregations of Shoal Bass within large shoal complexes appear to occur throughout most of the species’ range, including the upper Flint River (Goclowski et al. 2013), lower Flint River (Ingram et al. 2013, Taylor 2012), and tributaries of the middle Chattahoochee River (Sammons 2011). Shoal Bass are not unique in this adaptation; many other fluvial species are shoal-dependent or rely on shoal habitats at some point in their development (e.g., Hagler 2006). Our study provides direct qualitative evidence of homing ability in Shoal Bass. In a probabilistic sense, translocated fish had 5 general locations they could have eventually occupied: Muckalee Creek (tributary), Kinchafoonee Creek (tributary), the Flint River downstream of Lake Worth, the Flint River upstream of Lake Worth (their home tributary), or they could have remained in Lake Worth. The Flint River above and below Lake Worth is known to harbor robust Shoal Bass populations (Taylor and Peterson 2014), and Auburn University Natural History Museum (Auburn University, AL) records confirm that Shoal Bass have been collected in both Muckalee Creek and Kinchafoonee Creek. Not only did 10 of 12 translocated fish return upstream into the Flint River, but half (6 of 12) returned and remained within 1 rkm of their original capture site. In doing so, all 6 passed through several smaller shoal habitats and those that returned to Philema Shoals passed by another large Southeastern Naturalist A.T. Taylor and D.L. Peterson 2015 Vol. 14, No. 3 434 shoal complex at Abrams Shoals. Similar patterns of homing behavior have also been observed in fluvial populations of both M. dolomieu Lacepède (Smallmouth Bass; Langhurst and Schoenike 1990, VanArnum et al. 2004) and Largemouth Bass (Richardson-Heft et al. 2000). Interestingly, Ingram et al. (2013) translocated Shoal Bass from a spawning aggregation in the lower Flint River downstream to Lake Seminole and reported that no fish returned back to the capture area during their 90-d study. In their study, however, fish were displaced during and after the spawn, whereas in our study all fish were displaced just prior to spawning. Consequently, the homing behavior we observed may have simply reflected the seasonal tendency of Shoal Bass to move toward shoal complexes at the onset of the spawning season. The distance displaced may also affect Shoal Bass homing ability. In Ingram et al.’s (2013) study, fish were displaced approximately 90 rkm, whereas those in our study were only displaced 20–50 rkm. Despite the relatively small sample size of telemetered fish in our study, the 3 fish displaced the farthest (50 rkm) did not return to their original capture site, while many of the others did. The eventual fates of our fish revealed that fluvial-specialist Shoal Bass are capable of surviving translocation into lentic habitat in the short-term; however, the long-term effects of tournament-related translocation should be further evaluated. All 12 of our Shoal Bass survived the initial translocation into the impoundment, but our fish also had return access to riverine habitats. Whether or not Shoal Bass can survive translocation to a lentic habitat without return access to a lotic habitat remains unknown. Translocated fish may also emigrate from their original population, as was the case with 2 of 12 study fish that passed downstream of GPD. Although these fish were lost from the study population, their movement also illustrates that translocation into an impoundment may facilitate gene flow among populations fragmented by impoundments. Unfortunately, translocation associated with tournament angling during the summer months may increase post-release mortality of Shoal Bass because environmental conditions during the summer months may be particularly unfavorable. During our study, anglers translocated 2 of the telemetered fish into Lake Worth a second time during summer fishing tournaments, and both were eventually presumed dead near the weigh-in site at Cromartie Landing. Although the effects of angler-handling time and high water-temperatures have not been well-studied in Shoal Bass, previous studies on other Micropterus spp. have shown that both are positively correlated with post-release mortality of tournamentcaught fish (Edwards et al. 2004, Wilde 1998). In addition to being translocated into a suboptimal lentic environment, these factors could significantly increase the tournament- associated mortality of Shoal Bass. Of the 10 fish that returned upstream, 3 died within 6 months of their return (Table 1). Our findings were consistent with those of Ingram and Kilpatrick (2015) who estimated a 49% annual-mortality rate for adult Shoal Bass in the lower Flint River . Our study has several important conservation and management implications. The observed homing ability and the apparent importance of shoals as spawning habitat suggests that connectivity among these habitats is vital to effective Southeastern Naturalist 435 A.T. Taylor and D.L. Peterson 2015 Vol. 14, No. 3 conservation of Shoal Bass and other fluvial species. Additional investigation is warranted concerning the severity of fragmentation among populations in the heavily impounded native range of the Shoal Bass. Future studies of homing and spawning-site fidelity in Shoal Bass will help improve our current understanding of the critical linkages between habitat connectivity and the population dynamics of these and other fluvial-specialist fishes. Until such research is completed, we suggest that precautionary regulations regarding the translocation of Shoal Bass during fishing tournaments should be considered. For example, managers may wish to consider limiting the timeframe that tournament-related translocation is allowed. Post-release mortality of translocated Shoal Bass may be particularly problematic during the warmer summer months when water temperatures reach their seasonal highs. Likewise, translocation of adults during the spawning season may negatively affect spawning success. Other regulations that address the distance displaced and the potential for return access to shoal habitat may also be prudent. Although further research is needed to evaluate the effectiveness of such management actions, precautionary regulations like those suggested should help ensure the long-term sustainability of these important fisheries until a better understanding of their overall conservation status has been achieved. Acknowledgments We would like to thank the Georgia Department of Natural Resources for logistical support for this project, including the individual efforts of T. Ingram, J. Tannehill, and R. Weller with the Wildlife Resources Division, Fisheries Management Section. This manuscript was greatly improved by comments from Dr. James M. Long and 2 anonymous reviewers. We also thank D. Higginbotham, J. Swearingen, J. Keltner, F. Mathis, T. Faircloth, and H. Seymour for their assistance with data collection and field logisti cs. Literature Cited Bunn, S.E., and A.H. Arthington. 2002. Basic principles and ecological consequences of altered flow regimes for aquatic diversity. Environmental Management 30(4):492–507. Colle, D.E., R.L. Cailteux, and J.V. Shireman. 1989. Distribution of Florida Largemouth Bass in a lake after elimination of all submerged aquatic vegetation. North American Journal of Fisheries Management 9:213–218. Coutant, C.C., and R.R. Whitney. 2000. Fish behavior in relation to passage through hydropower turbines: A review. Transactions of the American Fisheries Society 129(2):351–380. Dakin, E.E., B.A. Porter, B.J. Freeman, and J.M. Long. 2007. Genetic integrity of an isolated population of Shoal Bass (Micropterus cataractae) in the upper Chattahoochee River basin. Natural Resource Technical Report NPS/NRWRD/NRTR-2007/366. National Park Service, Water Resources Division, Fort Collins, CO. 21 pp. Edwards, G.P., Jr., R.M. Neumann, R.P. Jacobs, and E.B. O’Donnell. 2004. Factors related to mortality of black bass caught during small club-tournaments in Connecticut. North American Journal of Fisheries Management 24(3):801–810. Fluker, B.L., B.R. Kuhajda, and P.M. Harris. 2014. The effects of riverine impoundment on genetic structure and gene flow in two stream fishes in the Mobile River basin. Freshwater Biology 59(3):526–543. Southeastern Naturalist A.T. Taylor and D.L. Peterson 2015 Vol. 14, No. 3 436 Freeman, M.C., and P.A. Marcinek. 2006. Fish-assemblage responses to water withdrawals and water supply reservoirs in Piedmont streams. Environmental Management 38(3):435–450. Goclowski, M.R., A.J. Kaeser, and S.M. Sammons. 2013. Movement and habitat differentiation among adult Shoal Bass, Largemouth Bass, and Spotted Bass in the upper Flint River, Georgia. North American Journal of Fisheries Management 33:56–70. Google Inc. 2013. Google Earth (Version 7.1.1.1888, software). Available online at http:// www.google.com/earth/. Accessed 2 September 2014. Hagler, M.M. 2006. Effects of natural flow variability over seven years on the occurrence of shoal-dependent fishes in the Etowah River. M.Sc. Thesis. University of Georgia, Athens, GA. 40 pp. Herbert, M.E., F.P. Gelwick, and W.L. Montgomery. 2003. Spatial variation of headwaterfish assemblages explained by hydrologic variability and upstream effects of impoundment. Copeia 2003(2):273–284. Hightower, J.E., J.R. Jackson, and K.H. Pollock. 2001. Use of telemetry methods to estimate natural fishing mortality of Striped Bass in Lake Gaston, North Carolina. Transactions of the American Fisheries Society 130(4):557–567. Hurst, H.N. 1969. Comparative life history of the Redeye Bass, Micropterus coosae Hubbs and Bailey, and the Spotted Bass, Micropterus p. punctulatus (Rafinesque), in Halawakee Creek, Alabama. M.Sc. Thesis. Auburn University, Auburn, AL. Ingram, T.R., and J.M. Kilpatrick. 2015. Assessment of the Shoal Bass population in the lower Flint River, Georgia. Pp. 157–168, In M.D. Tringali, M.S. Allen, T. Birdsong, and J.M. Long (Eds.). Black Bass Diversity: Multidisciplinary Science for Conservation. American Fisheries Society Symposium 82, Bethesda, MD. Ingram, T.R., J.E. Tannehill, and S.P. Young. 2013. Post-release survival and behavior of adult Shoal Bass in the Flint River, Georgia. North American Journal of Fisheries Management 33:717–722. International Game Fish Association. 2014. Shoal Bass (Micropterus cataractae). Available online at http://www.igfa.org/species/88-bass-shoal.aspx. Accessed 2 September 2014. Langhurst, R.W., and D.L. Schoenike. 1990. Seasonal migration of Smallmouth Bass in the Embarrass and Wolf rivers, Wisconsin. North American Journal of Fisheries Management 10:224–227. Maceina, M.J., J.W. Slipke, and J.M. Grizzle. 1999. Effectiveness of three barrier types for confining Grass Carp in embayments of Lake Seminole, Georgia. North American Journal of Fisheries Management 10:224–227. Moyle, P.B., and R.A. Leidy. 1992. Loss of biodiversity in aquatic ecosystems: Evidence from fish faunas. Pp. 127–170, In P.L. Feidler and S.K. Jain (Eds.). Conservation Biology: The Theory and Practice of Nature Conservation, Preservation, and Management. Chapman and Hall, New York, NY. 507 pp. Olden, J.D., and R.J. Naiman. 2009. Incorporating thermal regimes into environmental flows assessments: Modifying dam operations to restore freshwater-ecosystem integrity. Freshwater Biology 55(1):86–107. Poff, N.L., and J.K.H. Zimmerman. 2010. Ecological responses to altered flow regimes: A literature review to inform the science and management of environmental flows. Freshwater Biology 55:194–205. Porto, L.M., R.L. McLaughlin, and D.L.G. Noakes. 1999. Low-head barrier dams restrict the movement of fishes in two Lake Ontario streams. North American Journal of Fisheries Management 19(4):1028–1036. Southeastern Naturalist 437 A.T. Taylor and D.L. Peterson 2015 Vol. 14, No. 3 Postel, S., and B. Richter. 2003. Rivers for Life: Managing Water for People and Nature. Island Press, Washington DC. 220 pp. Pringle, C.M. 1997. Exploring how disturbance is transmitted upstream: Going against the flow. Journal of the North American Benthological Society 16:425–438. Quinn, J.W., and T.J. Kwak. 2003. Fish-assemblage changes in an Ozark river after impoundment: A long-term perspective. Transactions of the American Fisheries Society 132(1):110–119. Ricciardi, A., and J.B. Rasmussen. 2001. Extinction rates of North American freshwater fauna. Conservation Biology 13(5):1220–1222. Richardson-Heft, C.A., A.A. Heft, L. Fewlass, and S.B. Brandt. 2000. Movement of Largemouth Bass in northern Chesapeake Bay: Relevance to sportfishing tournaments. North American Journal of Fisheries Management 20(2):493–501. Sammons, S.M. 2011. Habitat use, movement, and behavior of Shoal Bass, Micropterus cataractae, in the Chattahoochee River near Bartletts Ferry Reservoir. Final Report submitted to Georgia Power. 64 pp. Sammons, S.M., and M.R. Goclowski. 2012. Relations between Shoal Bass and sympatric congeneric black bass species in Georgia rivers with emphasis on movement patterns, habitat use, and recruitment. Final Report to Georgia Department of Natural Resources, Social Circle, GA. 320 pp. Schilt, C.R. 2007. Developing fish passage and protection at hydropower dams. Applied Animal Behaviour Science 104:295–325. Schwemm, M.R. 2013. Zoogeography of Ouachita Highlands fishes. Ph.D. Dissertation. Oklahoma State University, Stillwater, OK. 136 pp. Taylor, A.T. 2012. Status assessment of a Shoal Bass population in the lower Flint River, Georgia. M.Sc. Thesis. University of Georgia, Athens, GA. 78 pp. Taylor, A.T., and D.L. Peterson. 2014. Shoal Bass life history and threats: A synthesis of current knowledge of a Micropterus species. Reviews in Fish Biology and Fisheries 24:159–167. Taylor, C.M., and R.J. Miller. 1990. Reproductive ecology and population structure of the Plains Minnow, Hybognathus placitus (Pisces: Cyprinidae), in central Oklahoma. American Midland Naturalist 123:32–39. Tyus, H.M., and C.A. Karp. 1990. Spawning movements of Razorback Sucker, Xyrauchen texanus, in the Green River Basin of Colorado and Utah. The Southwestern Naturalist 35(4):427–433. VanArnum, C.J.G., G.L. Buynak, and J.R. Ross. 2004. Movement of Smallmouth Bass in Elkhorn Creek, Kentucky. North American Journal of Fisheries Management 24:311–315. Wilde, G.R. 1998. Tournament-associated mortality in Black Bass. Fisheries 23(10):12–22. Wilkerson, M.L., and W.L. Fisher. 1997. Striped Bass distribution, movements, and site fidelity in Robert S. Kerr Reservoir, Oklahoma. North American Journal of Fisheries Management 17:677–686. Williams, J.D., and G.H. Burgess. 1999. A new species of bass, Micropterus cataractae (Teleostei: Centrarchidae), from the Apalachicola River Basin in Alabama, Florida, and Georgia. Bulletin of the Florida Museum of Natural History 42(2):80 –114. Winter, J.D. 1996. Advances in underwater biotelemetry. Pp. 555–590, In B.R. Murphy, and D.W. Willis (Eds.). Fisheries Techniques, 2nd Edition. American Fisheries Society, Bethesda, MD. 732 pp. Wright, S.E. 1967. Life history and taxonomy of the Flint River Redeye Bass (Micropterus coosae, Hubbs and Bailey). M.Sc. Thesis. University of Georgia, Athens, GA. 51 pp.