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Abstract
We reviewed the literature and gathered new radio telemetry data from the Otter Creek/Pecatonica River system in southwestern Wisconsin to examine general patterns in seasonal migrations by stream-dwelling smallmouth bass Micropterus dolomieu. During summer, smallmouth bass typically remain in localized areas, with net movements less than 1 km. In Otter Creek and the Pecatonica River movements were less than 200 m. In the fall, some smallmouth bass populations remain sedentary, while others migrate more than 75 km to reach winter habitat. Migration distance is correlated with winter severity; smallmouth bass move little in streams that do not freeze, but often travel more than 5 km in systems with ice. In the fall, most smallmouth bass left Otter Creek and entered the much larger Pecatonica River where they overwintered. Mean net movement between summer and winter habitats was 6.5 km (range 3.1-20.8 km). No smallmouth bass population has been observed to make long-distance movements during the winter. Winter habitat and activity levels vary among populations, and have little obvious relation with winter severity. In some systems, smallmouth bass occupy the deepest water available or areas of cover (boulders, logs), where they remain inactive for the winter. However, in other systems, smallmouth bass avoid the deepest holes, and are often active in areas with little cover. In the Otter/Pecatonica system, smallmouth bass occupied slow-moving runs (maximum depth 0.9-1.8 m) with limited cover during the winter and had home ranges that averaged 299 m in length (range 130-710 m). Many smallmouth bass populations undertake spawning migrations in the spring, usually to smaller tributaries. Migration distances vary, but may be greater than 10 km. Most smallmouth bass from Otter Creek that overwintered in the Pecatonica River, returned to Otter Creek during the spring. Mean net distance traveled was 6.5 km (range 0-11.5 km). Many smallmouth bass populations exhibit homing tendencies towards particular habitats. However, stocked smallmouth bass usually show little site fidelity, and quickly disperse long distances from the stocking location. Overall, movement tendencies differ dramatically among stream-dwelling smallmouth bass populations, suggesting that population-specific management strategies are needed.
... Individuals can move >100 km, even within populations where a subset of fish is non-mobile (i.e., moving <0.5 km; Rubenson & Olden, 2017;Schall et al., 2019). At the population level, movement extents and patterns of mobility among individuals vary considerably, thereby complicating the designation of "mobile" and "non-mobile" sub-groups (Lyons & Kanehl, 2002;Rubenson & Olden, 2017). In streams of the Ozark Highlands ecoregion, many smallmouth bass use springs as overwinter thermal refugia and follow similar movement patterns as northern populations around the spawning period, albeit with smaller movement extents (Peterson & Rabeni, 1996;Todd & Rabeni, 1989;Westhoff et al., 2016). ...
... The authors observed relatively mobile and sedentary individuals in each stream, as has been documented in other riverine smallmouth bass populations (Barthel et al., 2008;Gerber & Haynes, 1988;Rubenson & Olden, 2017;VanArnum et al., 2004) and stream fish in general (Lucas & Baras, 2001;Skalski & Gilliam, 2000). Tagged fish displayed greater mobility (both magnitude and rate) associated with spawning in the spring and reduced movement in other seasons (Lyons & Kanehl, 2002;Todd & Rabeni, 1989). The authors did not observe a concentration of movements to overwinter habitats, though these sometimes occur over a protracted period (i.e., summer-late autumn, Robbins & MacCrimmon, 1977). ...
... They found the effect of water temperature on fish movement was small and positive in spring but appeared less important in the smaller streams. The effects of temperature on smallmouth bass movements are variable, but increasing spring temperatures are a common movement cue for smallmouth bass before spawning (Barthel et al., 2008;Lyons & Kanehl, 2002). In general, the authors found lower movement rates and dampened relationships with environmental cues in the two smaller streams studied (Buffalo ...
Stream fish movement in response to changing resource availability and habitat needs is important for fish growth, survival and reproduction. The authors used radio telemetry to evaluate individual movements, daily movement rates, home ranges and habitat‐use characteristics of adult (278–464 mm LT) Neosho smallmouth bass Micropterus dolomieu velox in three Ozark Highlands streams from June 2016 to February 2018. The authors quantified variation in movement and habitat use among seasons and streams and examined relations with select environmental cues (i.e., temperature and discharge), fish size and sex. Maximum movement distances were an order of magnitude greater in the larger Elk River (17.0 km) and Buffalo Creek (12.9 km) than in the smaller Sycamore Creek (1.71 km), were similar in both upstream and downstream directions and typically occurred during the spring. Most movement rates were ≤10 m day⁻¹ in all streams and seasons, except for Elk River during spring. Ranking of linear mixed‐effects models using AICc supported that movement rates were much greater in spring and increased with stream size. Spring movement rate increased with discharge and water temperature; only weak relationships were apparent during other seasons. Increased variation in water temperature had a small negative effect on movement rate. Home range size was highly variable among individuals, ranging 45–15,061 m (median: 773 m), and was not related to fish size, sex, season or stream. Although some fish moved between rivers, this study's tagged fish did not use reservoir or associated interface habitat. Water temperatures used by this study's tagged fish followed seasonal patterns but indicated the use of thermal refugia during summer and winter. Deeper‐water habitats were used in Buffalo Creek and in winter across all study streams, whereas greater velocities used in the Elk River likely reflect the increased use of run habitats. Use of pool habitats predominated among tagged fish, particularly in smaller streams. The results of this study indicate considerable heterogeneity in movement and habitat use within and among lotic populations of Neosho smallmouth bass. These findings suggest that population‐specific management may be appropriate and highlight the importance of natural flow conditions (i.e., spring high flows) and connected habitats for this endemic sport fish, particularly in smaller streams.
... Smallmouth bass in river networks are known to move among habitat types both seasonally (Todd and Rabeni 1989;Langhurst and Schoenike 1990;Westhoff et al. 2016) and ontogenetically (Probst et al. 1984;Sabo and Orth 1994;Humston et al. 2010Humston et al. , 2017. Smallmouth bass in river systems may migrate upstream to tributaries to minimize risks of nest failure due to washout in high flows or to nest predation (Lyons and Kanehl 2002). Reproductive homing of smallmouth bass in river systems, however, is as yet uncharacterized. ...
... In each case, we took the conservative approach of choosing the tributary closest to the sampling location with a reasonably matching 87 Sr/ 86 Sr when approximating natal origins. Smallmouth bass are known to utilize smaller tributaries for spawning (Lyons and Kanehl 2002); therefore, we considered any persistent tributary of Strahler order 2 or higher to be potential spawning locations. Ephemeral and intermittent streams were excluded from consideration. ...
... We also reviewed other studies on smallmouth bass population genetics as well as mark-recapture and telemetry studies in riverine habitats for comparison of our results to observations from other systems. Smallmouth bass are known to occupy different habitats for spawning (spring), summer, and winter seasons (Lyons and Kanehl 2002;Ridgway et al. 2002) and in some cases undertake substantial migrations between seasonal habitats (Langhurst and Schoenike 1990;Lyons and Kanehl 2002;Westhoff et al. 2016). Therefore, we restricted our review of movement studies to only those where movement was observed over a period that encompassed these three seasons. ...
Quantifying the scale of offspring dispersal is essential for understanding demographic connectivity across landscapes and rates of population spread. However, characterizing natal dispersal in fishes is complicated by the difficulties of tracking origins and movement during early life-history stages. We combined direct observation of natal dispersal based on otolith chemistry with indirect estimates of dispersal from population genetics to quantify intergenerational dispersal of smallmouth bass (Micropterus dolomieu) inhabiting a river network. Average parent–offspring dispersal was estimated as 7.7 km from genetic isolation-by-distance and demographic population data. Otolith chemistry indicated that adults were captured an average of 8.3 km from their natal tributary, supporting the genetics-based estimate. Our estimate of intergenerational dispersal is higher than previous estimates for lotic fishes and considerably higher than estimates for smallmouth bass in lake systems. Differences in availability of seasonal habitats for smallmouth bass may account for the contrasting scales of dispersal between lake and river populations. The large intergenerational dispersal distance of riverine smallmouth bass should be considered in conservation of fisheries or efforts to control invasive populations in river networks.
... and management priorities for ensuring the future persistence of riverine species (Pracheil, McIntyre & Lyons, 2013). For smallmouth bass, as an example, it has been recommended that sport fishing regulations, including closed seasons or catch-and-release angling, consider movement dynamics to account for all habitats and areas used by the species seasonally (Lyons & Kanehl, 2002). ...
... size, stream depth, connectivity, hydrology; Brewer, Rabeni, Sowa & Annis, 2007;Dauwalter, Splinter, Fisher & Marston, 2007;Humston, Priest, Hamilton & Bugas, 2010;Brewer, 2011). Due to the variability in smallmouth bass movement among river systems and differences in stream habitats and conditions within studies, extrapolation of results to other, unstudied, systems may not be appropriate (Lyons & Kanehl, 2002). Similar to other species, smallmouth bass movement has been shown to vary seasonally and to be influenced by environmental factors (Hafs, Gagen & Whalen, 2010;Todd & Rabeni, 1989) and habitat characteristics (Beam, 1990;Dauwalter & Fisher, 2008). ...
... Funk, 1955;<8 km, Todd & Rabeni, 1989). Inherent variability among river systems, including size, connectivity, in-stream habitat, food availability and anthropogenic disturbances, could all contribute to smallmouth bass habitat use and movement patterns (Brewer, 2011;Brewer et al., 2007;Humston et al., 2010;Lyons & Kanehl, 2002). Studies that documented limited smallmouth bass movement, such as the work of Todd and Rabeni (1989), may have taken place in streams where local habitat requirements adequately meet life history requirements and therefore reduce the need for long-range movements. ...
Smallmouth bass, Micropterus dolomieu Lacepède, movement dynamics were investigated in a connected mainstem river‐tributary system. Smallmouth bass moved large distances annually (n = 84 fish, average = 24.6 ± 25.9 km, range = 0.03 to 118 km) and had three peak movement periods (pre‐spawn, post‐spawn and overwintering). Movement into and out of tributaries was common, but the movement between mainstem river and tributary habitats varied among tagging locations and season. In general, a large proportion of fish that were tagged in tributaries moved out of the tributaries after spawning (22/30 fish). Because of the importance of fish movement patterns on population dynamics, the observed individual variability in movement, quantified using a hierarchical model, and the potential for long‐distance movements are important considerations for smallmouth bass conservation and management. In addition, mainstem river‐tributary connectivity appears to play an important role for smallmouth bass during key life history events.
... Migratory patterns related to seasonal shifts in habitat use and fidelity to spawning sites and seasonal home ranges have been described in lake populations (Ridgway et al., 2002), including adfluvial life-history patterns (Barthel et al., 2008). Lyons and Kanehl (2002) reviewed studies from lotic M. dolomieu populations and described a diversity of documented behaviours and patterns, including some studies suggesting movement into tributaries for spawning. Recent studies documenting the use of thermal refuge habitats in rivers (groundwater inputs) indicate the likelihood of seasonal movement for behavioural thermoregulation in river systems Westhoff et al., 2016). ...
... All of these fish left their natal tributary early in their first year and were recaptured several km from the nearest major tributary. Lyons & Kanehl (2002) noted that there was limited evidence characterizing dispersal of M. dolomieu, particularly in the first few months post-spawning. They suggested that downstream advection of YOY by flood pulses could lead to extensive displacement of YOY M. dolomieu. ...
... Therefore, advection cannot be the sole or dominant mode of early juvenile dispersal. Lyons & Kanehl (2002) also cited unpublished data on observations of YOY found 'several km' upstream in smaller tributaries where spawning was improbable, but they did not offer insight into how commonly this occurred. Barthel (2010) estimated natal dispersal distances of age-1 year M. dolomieu using genetic data and paternity assignment methods, and reported that median dispersal distance of river-spawned cohorts was generally <300 m. ...
Radiogenic strontium isotope ratios (87Sr:86Sr) in otoliths were compared with isotope ratios predicted from models and observed in water sampling to reconstruct the movement histories of smallmouth bass Micropterus dolomieu between main-river and adjacent tributary habitats. A mechanistic model incorporating isotope geochemistry, weathering processes and basin accumulation reasonably predicted observed river 87Sr:86Sr across the study area and provided the foundations for experimental design and inferring fish provenance. Exchange between rivers occurred frequently, with nearly half (48%) of the 209 individuals displaying changes in otolith 87Sr:86Sr reflecting movement between isotopically distinct rivers. The majority of between-river movements occurred in the first year and often within the first few months of life. Although more individuals were observed moving from the main river into tributaries, this pattern did not necessarily reflect asymmetry in exchange. Several individuals made multiple movements between rivers over their lifetimes; no patterns were found, however, that suggest seasonal or migratory movement. The main-river sport fishery is strongly supported by recruitment from tributary spawning, as 26% of stock size individuals in the main river were spawned in tributaries. The prevailing pattern of early juvenile dispersal documented in this study has not been observed previously for this species and suggests that the process of establishing seasonal home-range areas occurs up to 2 years earlier than originally hypothesized. Extensive exchange between rivers would have substantial implications for management of M. dolomieu populations in river–tributary networks.
... in movement patterns by tagged smallmouth bass, which is known to occur in other streams (Munther 1970;Lyons & Kanehl 2002;Gunderson VanArnum et al. 2004). The longest movement we observed was 42.5 km, which was greater than the maximum 7.5 km movement of smallmouth bass previously documented in this stream (Todd & Rabeni 1989), and our maximum and average movement distances were greater than observed for most smallmouth bass populations, but within the range documented for smallmouth bass (Lyons & Kanehl 2002;Hafs et al. 2010). ...
... in movement patterns by tagged smallmouth bass, which is known to occur in other streams (Munther 1970;Lyons & Kanehl 2002;Gunderson VanArnum et al. 2004). The longest movement we observed was 42.5 km, which was greater than the maximum 7.5 km movement of smallmouth bass previously documented in this stream (Todd & Rabeni 1989), and our maximum and average movement distances were greater than observed for most smallmouth bass populations, but within the range documented for smallmouth bass (Lyons & Kanehl 2002;Hafs et al. 2010). The longest documented migration by smallmouth bass was 109 km in a Wisconsin stream during autumn when water temperatures fell below 16°C and in conjunction with a rain event (Langhurst & Schoenike 1990). ...
... Funk (1955) estimated that for riverine smallmouth bass in Missouri 63% were sedentary (<1.6 km movement) and 37% were mobile (>1.6 km movement), with 8% moving over 40 km. The high amount of variation observed in smallmouth bass movement and migration patterns suggests complex behavioural responses by individual fish are likely, may be age and sex dependent, and likely vary annually (Funk 1955;Lyons & Kanehl 2002). The mixture of migrating and resident individuals demonstrates a pattern of partial migration, which is condition dependent and often closely linked to genetic or phenotypic attributes of individuals (Chapman et al. 2011). ...
Smallmouth bass in thermally heterogeneous streams may behaviourally thermoregulate during the cold period (i.e., groundwater temperature greater than river water temperature) by inhabiting warm areas in the stream that result from high groundwater influence or springs. Our objectives were to determine movement of smallmouth bass (Micropterus dolomieu) that use thermal refuge and project differences in growth and consumption among smallmouth bass exhibiting different thermal-use patterns. We implanted radio transmitters in 29 smallmouth bass captured in Alley Spring on the Jacks Fork River, Missouri, USA, during the winter of 2012. Additionally, temperature archival tags were implanted in a subset of nine fish. Fish were tracked using radio telemetry monthly from January 2012 through January of 2013. The greatest upstream movement was 42.5 km, and the greatest downstream movement was 22.2 km. Most radio tagged fish (69%) departed Alley Spring when daily maximum river water temperature first exceeded that of the spring (14 °C) and during increased river discharge. Bioenergetic modelling predicted that a 350 g migrating smallmouth bass that used cold-period thermal refuge would grow 16% slower at the same consumption level as a fish that did not seek thermal refuge. Contrary to the bioenergetics models, extrapolation of growth scope results suggested migrating fish grow 29% more than fish using areas of stream with little groundwater influence. Our results contradict previous findings that smallmouth bass are relatively sedentary, provide information about potential cues for migratory behaviour, and give insight to managers regarding use and growth of smallmouth bass in thermally heterogeneous river systems.
... Largemouth bass are generally considered sedentary species in lakes and reservoirs (Lyons 1995;Sammons and Maceina 2005); however, this species has been observed to move 10-20 km to overwintering areas in lotic systems (Raibley et al. 1997;Karchesky and Bennett 2004). In contrast, smallmouth bass moved up to 109 km to reach overwintering areas in northern rivers (Langhurst and Schoenike 1990), but most authors have found smallmouth bass to be relatively sedentary in rivers, similar to largemouth bass (Munther 1970;Todd and Rabeni 1989;Lyons and Kanehl 2002;VanArnum et al. 2004). Spotted bass Micropterus punctulatus have been less studied than largemouth bass and smallmouth bass, but movement of this species in rivers has been reported to be similar to these congenerics (Horton and Guy 2002;Goclowski et al. ...
... Migration has been defined as movements that result in a displacement between two or more well-separated habitats, occur with regular periodicity (often annual), involve a large fraction of the population, and are at some period directed towards specific areas rather than random wandering (Northcote 1997). Shoal bass in the Flint River, especially those in the Lyons and Kanehl 2002;Karchesky and Bennett 2004). However, spring migrations to spawning grounds are much less commonly reported for black bass. ...
... Montgomery et al. (1980) documented limited potamodromy of smallmouth bass in the Columbia River, Washington, where fish in one area migrated downstream up to 63 km away from their spawning area, whereas, another group showed limited dispersal. Lyons and Kanehl (2002) reported a few instances of spring migration by smallmouth bass to spawning areas, but overall, evidence of true potamodromy in Micropterus spp. remains equivocal. ...
... Ridgway et al. (2002) reviewed the evidence for a dynamic spatial ecology of smallmouth bass and suggested that density-dependent processes during the juvenile phase were important mechanisms for determining spatial structure in the distribution of adults (''juvenile transition hypothesis''). Their analysis focused on lentic populations; however, a large body of literature exists describing movement behavior and spatial dynamics in stream and river populations (Larimore 1952;Todd and Rabeni 1989;Langhurst and Schoenike 1990;Lyons and Kanehl 2002;VanArnum et al. 2004). Unfortunately, data on movement in the juvenile stage are lacking due to the challenges of marking or tracking small individuals (Lyons and Kanehl 2002). ...
... Their analysis focused on lentic populations; however, a large body of literature exists describing movement behavior and spatial dynamics in stream and river populations (Larimore 1952;Todd and Rabeni 1989;Langhurst and Schoenike 1990;Lyons and Kanehl 2002;VanArnum et al. 2004). Unfortunately, data on movement in the juvenile stage are lacking due to the challenges of marking or tracking small individuals (Lyons and Kanehl 2002). Gross et al. (1994) used genetic fingerprinting to identify nest of origin in Lake Opeongo, Ontario, and observed only limited dispersal of age-0 smallmouth bass away from nest sites (most individuals being captured within 200 m of their nest; Ridgway et al. 2002). ...
... Periods of high stream discharge during spawning and early growth can cause poor growth, high mortality, or both of age-0 smallmouth bass due to nest scouring, fry displacement, or other mechanisms (Cleary 1956;Simonson and Swenson 1990;Lukas and Orth 1995;Sabo and Orth 1994;Orth and Newcomb 2002). However, little attention has been paid to dispersal of age-0 recruits and the possible implications for recruitment variability and spatial dynamics of riverine stocks (Lyons and Kanehl 2002). Though smallmouth bass are not considered to be prone to larval drift (see results in Gale and Mohr 1978;Muth and Schmulbach 1984;observations by Simonson and Swenson 1990;Sabo and Orth 1994), it is possible that high-flow conditions could result in advective transport during larval and early juvenile stages. ...
Juvenile dispersal and the exchange of offspring among fish populations in river–tributary networks are difficult to characterize, but they may play a substantial role in the dynamics of fisheries in these systems. We used geochemical signatures in otoliths to identify the natal origins of young-of-year smallmouth bass Micropterus dolomieu in the James River and a tributary, the Maury River, in Virginia. The trace element signatures (Sr:Ca, Rb:Ca, Mg:Ca, and Ba:Ca) in otoliths differed significantly between these two rivers, resulting in approximately 87% accuracy in classifying known-origin fry to their natal rivers. The variation in otolith composition reflected the variation in water chemistry within the system. We subsequently used classification functions and stock mixture analyses based on these signatures to identify the natal origins of age-1 juveniles collected from the same rivers 1 year later. The results indicate that approximately 50% of the age-1 smallmouth bass collected in the James River were spawned in the Maury River, while no evidence for reciprocal main stem-to-tributary exchange was found. These results suggest that the downstream movement and dispersal of smallmouth bass is common in their first year of life. Such inputs from tributaries may play an important role in the dynamics of smallmouth bass river fisheries, which are often characterized by substantial annual variation in recruitment. Characterizing such exchange at broader scales will probably be an important step toward linking the spatial ecology of this species with effective management and conservation strategies in river–tributary networks.
... Smallmouth and Neosho Bass populations exhibit inconsistent dispersal and migratory behavior. Some are sedentary (Funk, 1957) due to philopatry and nest-site fidelity (Ridgway et al., 1991), while others are seasonally potamodromous (Funk, 1957;Gowan et al., 1994;Lyons & Kanehl, 2002); these behaviors may to some degree vary by species (Miller & Brewer, 2021). ...
... Some Smallmouth Bass individuals are sedentary (Funk, 1957) as a result of philopatry (Ridgway et al., 1991), which may contribute to reproductive isolation between populations and allow for random fixation of distinct alleles. While some fish may also be migratory, when migration occurs, it is typically seasonal (Funk, 1957;Gowan et al., 1994;Lyons & Kanehl, 2002). Abbreviations: θ, genetic diversity considering only polymorphic SNPs; AM, divergence with asymmetric migration; AM2E, divergence, asymmetric migration between two distinct epochs; nu 1 , size of population 1; nu 2 , size of population 2; m 12 , continuous migration rate from population 2 to population 1; m 12a , migration rate from population 2 to population 1 during first epoch; m 12b , migration rate from population 2 to population 1 during second epoch; m 21 , continuous migration rate from population 1 to population 2; m 21a , migration rate from population 1 to population 2 during first epoch; m 21b , migration rate from population 1 to population 2 during second epoch; SCAM, divergence, isolation, and secondary contact with asymmetric migration; T 1 , scaled time between split and migration event; ...
The Neosho Bass (Micropterus velox), a former subspecies of the keystone top-predator and globally popular Smallmouth Bass (M. dolomieu), is endemic and narrowly restricted to small, clear streams of the Arkansas River Basin in the Central Interior Highlands (CIH) ecoregion, USA. Previous studies have detected some morphological, genetic, and genomic differentiation between the Neosho and Smallmouth Basses; however, the extent of neutral and adaptive divergence and patterns of intraspecific diversity are poorly understood. Furthermore, lineage diversification has likely been impacted by gene flow in some Neosho populations, which may be due to a combination of natural biogeographic processes and anthropogenic introductions. We assessed: (1) lineage divergence, (2) local directional selection (adaptive divergence), and (3) demographic history among Smallmouth Bass populations in the CIH using population genomic analyses of 50,828 single-nucleotide polymorphisms (SNPs) obtained through ddRAD-seq. Neosho and Smallmouth Bass formed monophyletic clades with 100% bootstrap support. We identified two major lineages within each species. We discovered six Neosho Bass populations (two nonadmixed and four admixed) and three nonadmixed Smallmouth Bass populations. We detected 29 SNPs putatively under directional selection in the Neosho range, suggesting populations may be locally adapted. Two populations were admixed via recent asymmetric secondary contact, perhaps after anthropogenic introduction. Two other populations were likely admixed via combinations of ancient and recent processes. These species comprise independently evolving lineages, some having experienced historical and natural admixture. These results may be critical for management of Neosho Bass as a distinct species and may aid in the conservation of other species with complex biogeographic histories.
... Much of the literature on invasive species in streams is focused on diet and impact on native species (e.g., see McDowall 2003;Olden et al. 2006;Weber and Brown 2009). However, there has been a more thorough examination of habitat requirements, occupation and density of intentionally introduced salmonids (e.g., see Cunjak and Power 1986;Zorn 2017), as well as smallmouth bass (Micropterus dolomieu) (Lyons and Kanehl 2002), and parallels can be drawn with the round goby. Non-anadromous juvenile salmonids are known to emigrate from some Idaho streams in winter, whereas other streams are occupied year-round. ...
... However, in streams lacking cobble, juvenile salmonids emigrate (Bjornn 1971). The small body size of the round goby and its affinity for cobble/ boulder substrate may predispose it to overwinter in streams, whereas larger stream fishes such as adult salmonids (Brown et al. 2011 and references therein) and smallmouth bass (Lyons and Kanehl 2002) may leave the stream in search of suitable winter habitat. Like juvenile salmonids in streams with cobble substrate, round gobies in the Otonabee River tributaries may be occupying spaces between cobble/ boulder substrate through winter. ...
Since its introduction to North America in the 1990s, the round goby has spread throughout the Great Lakes and inland movement into small tributaries, a new environment for this species in both its native and invaded ranges, is becoming more prevalent. We assessed spatial and temporal occupation of round gobies in four small streams in two systems in south-central Ontario, Canada to determine which habitat variables are the best predictors of round goby density. Two streams are tributaries of Lake Ontario and two are tributaries of the Otonabee River; all of these streams have barriers preventing upstream migration. Occupation and density patterns differed between the systems. In the Lake Ontario system, density was highest near the longitudinal centre of the stream between the mouth and first barrier, and round goby appeared to occupy these streams mainly from spring to fall. In the Otonabee River system, round goby occupied the streams year-round, and the most important factor determining adult density was distance from a barrier to upstream movement, with density highest next to the barriers. Adult density in Lake Ontario tributaries was highest in sites with a high percentage of cobble/boulder and a low percentage of gravel substrate, while substrate was less important in Otonabee River tributaries. Date was the strongest predictor of juvenile density, with density increasing through the sampling period in both systems. Occupation and density patterns may differ due to contrasting environmental conditions in the source environments and distance to the first barrier preventing upstream movement. This study shows diversity in invasion strategies, and provides insight into the ability of invasive species to change their occupation strategies based on the different environments they encounter.
... Movement and habitat associations are well understood for black bass with broad distributions and wide habitat preferences, such as largemouth bass (Micropterus salmoides; Lacepede , 1802) and smallmouth bass (M. dolomieu; Lacepede, 1802) (Todd & Rabeni, 1989; Lyons, 1995; Raibley et al., 1997; Lyons & Kanehl, 2002; Sammons & Maceina, 2005). Movement patterns are less understood for regionally endemic black bass species, but have generally been considered to exhibit behaviors similar to their more-studied congeneric species. ...
... However, neither study determined whether fish spawned in tributary streams and migrating downstream were the product of migratory adults from the estuary or resident fish. A review by Lyons & Kanehl (2002) of smallmouth bass movement studies in lotic systems found that most spring migrations were less than 10 km, but a few instances of longer migrations (up to 75 km) were reported. Despite these studies, evidence of true potamodromy in other black bass species remains equivocal. ...
Potamodromy, migration for reproduction within freshwater systems, is widely practiced among fishes, but has rarely been reported for Micropterus spp. Recent evidence has shown that shoal bass (M. cataractae; Williams & Burgess, 1999) in the upper Flint River, USA, undergo migrations during the spawning season to large shoal complexes; however, the magnitude and prevalence of these migrations are unknown. To test the hypothesis that these fish exhibit potadromy, 376 shoal bass were tagged with anchor tags over a four-year period. Each spring, shoal bass migrated up to 200 km to reach spawning areas in the piedmont, and these migrations appeared to be more common in fish living in the coastal plain area of the river. Fish from the piedmont area moved less, likely due to proximity of spawning habitat. Results of this study have suggested that shoal bass are highly migratory in connected systems, traveling long distances to spawn in specific areas. Thus, the scope of shoal bass management and conservation has broadened considerably. Other Micropterus species dwelling in lotic habitats may exhibit similar migratory patterns in their native and/or introduced ranges, and this possibility could be examined using mark-recapture techniques similar to those used in this study.
... In contrast, yellow perch (control region mean F ST = 0.469, μsat = 0.236) [67] and smallmouth bass (cytochrome b mean F ST = 0.412, μsat = 0.232) [64,70] possess much higher divergence among spawning groups. This may be due to their more limited migration [71,72]. Walleye have been documented to disperse 50-300 km [73], followed by yellow perch to 48 km, with occasional individuals travelling 200 km [71], and smallmouth bass only to~10 km [72]. ...
... This may be due to their more limited migration [71,72]. Walleye have been documented to disperse 50-300 km [73], followed by yellow perch to 48 km, with occasional individuals travelling 200 km [71], and smallmouth bass only to~10 km [72]. ...
Loss of unique taxa and declining species diversity are growing problems that threaten ecosystems worldwide, often accompanying exploitation, habitat alteration, and pollution. The North American Great Lakes – the world’s largest freshwater ecosystem - once housed a putatively unique percid fish taxon in Lake Erie, termed the blue “pike” Sander vitreus glaucus, until its popular and abundant fishery crashed in the early 1960s. The blue pike was declared extinct and Lake Erie was termed ecologically “dead” in the 1970s due to pollution. Lake Erie has since recovered, and supports an abundant walleye fishery today, but the blue pike has not been seen again. It has long been questioned whether the blue pike was a distinct species, subspecies, or an ecophenotypic variant of the “yellow” walleye Sander vitreus vitreus. DNA sequencing of the mtDNA control region and analyses of nuclear DNA microsatellites of historic material, offer the means to understand the blue pike’s evolutionary and biogeographic relationships, and determine whether it genetically hybridized with yellow walleye. We analyzed 20 of the blue pike paratypes described by Hubbs in 1926 in comparison with genetic and morphological data of 20 historic walleye from Lake Erie, along with 800+ modern walleye from Lake Erie and throughout their North American range. Results indicate no diagnostic genetic or morphological characters differences between the blue pike and yellow walleye, with some slight sampling trends in their interorbital distances and head widths. In contrast, walleye show considerable population genetic differences among spawning locations and geographic regions across their range. Our results indicate that the extinct blue pike did not merit taxonomic distinction.
... In contrast, yellow perch (control region mean F ST = 0.469, µsat = 0.236) [67] and smallmouth bass (cytochrome b mean F ST = 0.412, µsat = 0.232) [64,70] possess much higher divergence among spawning groups. This may be due to their more limited migration [71,72]. Walleye have been documented to disperse 50-300 km [73], followed by yellow perch to 48 km, with occasional individuals travelling 200 km [71], and smallmouth bass only to ~10 km [72]. ...
... This may be due to their more limited migration [71,72]. Walleye have been documented to disperse 50-300 km [73], followed by yellow perch to 48 km, with occasional individuals travelling 200 km [71], and smallmouth bass only to ~10 km [72]. ...
Background:
Conserving genetic diversity and local adaptations are management priorities for wild populations of exploited species, which increasingly are subject to climate change, habitat loss, and pollution. These constitute growing concerns for the walleye Sander vitreus, an ecologically and economically valuable North American temperate fish with large Laurentian Great Lakes' fisheries. This study compares genetic diversity and divergence patterns across its widespread native range using mitochondrial (mt) DNA control region sequences and nine nuclear DNA microsatellite (μsat) loci, examining historic and contemporary influences. We analyze the genetic and morphological characters of a putative endemic variant- "blue pike" S. v. "glaucus" -described from Lakes Erie and Ontario, which became extinct. Walleye with turquoise-colored mucus also are evaluated, since some have questioned whether these are related to the "blue pike".
Results:
Walleye populations are distinguished by considerable genetic divergence (mean FST mtDNA = 0.32 ± 0.01, μsat = 0.13 ± 0.00) and substantial diversity across their range (mean heterozygosity mtDNA = 0.53 ± 0.02, μsat = 0.68 ± 0.03). Southern populations markedly differ, possessing unique haplotypes and alleles, especially the Ohio/New River population that houses the oldest haplotype and has the most pronounced divergence. Northern formerly glaciated populations have greatest diversity in Lake Erie (mean heterozygosity mtDNA = 0.79 ± 0.00, μsat = 0.72 ± 0.01). Genetic diversity was much less in the historic Lake Erie samples from 1923-1949 (mean heterozygosity mtDNA = 0.05 ± 0.01, μsat = 0.47 ± 0.06) than today. The historic "blue pike" had no unique haplotypes/alleles and there is no evidence that it comprised a separate taxon from walleye. Turquoise mucus walleye also show no genetic differentiation from other sympatric walleye and no correspondence to the "blue pike".
Conclusions:
Contemporary walleye populations possess high levels of genetic diversity and divergence, despite habitat degradation and exploitation. Genetic and previously published tagging data indicate that natal homing and spawning site philopatry led to population structure. Population patterns were shaped by climate change and drainage connections, with northern ones tracing to post-glacial recolonization. Southerly populations possess unique alleles and may provide an important genetic reservoir. Allelic frequencies of Lake Erie walleye from ~70-90 years ago significantly differed from those today, suggesting population recovery after extensive habitat loss, pollution, and exploitation. The historic "blue pike" is indistinguishable from walleye, indicating that taxonomic designation is not warranted.
... For example, largemouth bass spawn on open nests in deep pools and move on the order of kilometers from overwintering to spawning habitats (Mesing and Wicker 1986; Raibley et al. 1997). Conversely, smallmouth bass spawn within overhead cover and generally remain within a single mesohabitat during spawning but exhibit migrations up to 24 km (Todd and Rabeni 1989; Lyons and Kanehl 2002; VanArnum et al. 2004). Spotted bass exhibit little movement (e.g., 18 m/h; Horton and Guy 2002) and generally remain within or close to a single pool, where spawning occurs on gravel bars (Viosca 1931; Horton and Guy 2002). ...
... Micropterus spp. are primarily sedentary in streams and rivers (movement ,1.6 km; Funk 1957), but more mobile largemouth and smallmouth bass individuals travel up to 24 km (Funk 1957; Raibley et al. 1997; Lyons and Kanehl 2002; VanArnum et al. 2004). ...
The Guadalupe bass Micropterus treculii is endemic to Texas and is threatened by introgression with introduced smallmouth bass M. dolomieu as well as habitat degradation. This study described and quantified the movements and habitat associations of Guadalupe bass to assess the factors that may influence current populations. Radio-tagged adult Guadalupe bass were tracked in the Pedernales River (n = 12) and South Llano River (n = 12) from January through August 2008. Available microhabitats were measured and modeled in terms of depth, velocity, substrate, and cover for about 1.5 km in the Pedernales River and 1.2 km in the South Llano River. Rates of movement were greatest during the reproductive season, ranging from less than 1 to 9 m/d. Instream cover (such as undercut banks and woody debris) was preferred during daylight hours throughout the study period, although the distances from cover increased from January to August. Habitat shifts from cover to open water occurred at night and from woody structures to boulders and ledges during a large flood pulse. The habitats most suitable for adult Guadalupe bass had a depth of 1.0 m and a current velocity of 0.05 m/s, and habitat selection was strongest for eddy mesohabitats with smaller substrates. By July, the Guadalupe bass in the South Llano River were associated with runs with greater current velocities, whereas those in the Pedernales River were associated with pools with greater depths, largely owing to the low flows and reduced habitat availability in the Pedernales River. Environmental factors, including the availability and suitability of instream cover, are probably the strongest influences on the distribution and abundance of Guadalupe bass.
... Tagging studies have shown that movements of individuals usually are limited to a few kilometres and demonstrate appreciable homing tendency (Ridgway & Shuter 1996;Hodgson et al . 1998;Lyons & Kanehl 2002), indicating potential for significant population genetic structure. Acquiring and defending a home range and successfully foraging in social groups appear prerequisite for reproductive success (Ridgway et al . ...
... Tagging data for smallmouth bass have implicated homing (Ridgway & Shuter 1996;Hodgson et al. 1998;Lyons & Kanehl 2002) and nest locations remain stable from yearto-year (Rejwan et al. 1997), suggesting high potential for genetic structure of spawning populations, which is supported by our results. When adults return to the close proximity of natal sites to spawn, the genetic differentiation among closely spaced populations will increase over time thereby producing fine-scale divergences as observed in this study. ...
Analysis of population genetic relationships reveals the signatures of current processes such as spawning behaviour and migration, as well as those of historical events including vicariance and climate change. This study examines these signatures through testing broad- to fine-scale genetic patterns among smallmouth bass Micropterus dolomieu spawning populations across their native Great Lakes range and outgroup areas, with fine-scale concentration in Lake Erie. Our primary hypotheses include whether genetic patterns result from behavioural and/or geographical isolation, specifically: (i) Are spawning groups in interconnected waterways genetically separable? (ii) What is the degree of isolation across and among lakes, basins, and tributaries? (iii) Do genetic divergences correspond to geographical distances? and (iv) Are historical colonization patterns from glacial refugia retained? Variation at eight nuclear microsatellite DNA loci are analysed for 666 smallmouth bass from 28 locations, including 425 individuals in Lake Erie; as well as Lakes Superior, Huron, and Ontario, and outgroups from the Mississippi, Ohio, St. Lawrence, and Hudson River drainages. Results reveal marked genetic differences among lake and river populations, as well as surprisingly high divergences among closely spaced riverine sites. Results do not fit an isolation-by-geographical-distance prediction for fine-scale genetic patterns, but show weak correspondence across large geographical scales. Genetic relationships thus are consistent with hypotheses regarding divergent origins through vicariance in glacial refugia, followed by colonization pathways establishing modern-day Great Lakes populations, and maintenance through behavioural site fidelity. Conservation management practices thus should preserve genetic identity and unique characters among smallmouth bass populations.
... Instead of using the percentage of an area deeper than 1.2 m to calculate HSI D we used the percent deeper than 2 m (Fig. 1). Although this percentage was slightly deeper than the depth requirement in the initial model presented by Palesh and Anderson (1990), it was an appropriate adjustment given that bluegills have been generally observed to prefer deeper overwintering areas in rivers (Lyons and Kanehl 2002) and have been observed to prefer backwaters with depths greater than 2 m in the UMRS during winter (Laaker 2020). We also used the recommended maximum threshold for suitable flow velocity of 3 cm·s −1 , which is stricter than the original bluegill HSI F that would not reach an index of 0. ...
Availability of suitable overwintering habitat is crucial for the survival of centrarchids in large floodplain rivers. However, there remains uncertainty in the spatiotemporal drivers of suitable conditions. We paired hydrogeomorphic characteristics with environmental data from 1994 to 2018 in individual lentic areas to (1) assess overwintering habitat availability throughout the Upper Mississippi River System using existing habitat suitability indices (HSIs) and (2) explore potential drivers of overall habitat suitability (HSIO) and its components (dissolved oxygen, temperature, and flow). We found that flow velocities that exceeded suitable thresholds were independently responsible for 53% of nonsuitable habitats, and connectivity with lotic channels and river discharge increased velocity within lentic habitats. Additionally, colder winter conditions reduced water temperature, reducing availability of highly suitable habitat. Our results indicate that although warmer winters could increase the availability of highly suitable habitat for centrarchids, changes in flow regimes could lead to more connected areas becoming unsuitable. Our results provide critical information on factors that can be prioritized to manage centrarchid habitat, which is especially important in the context of uncertain future climate.
... (Null models with these added constraints yield the same conclusion as our basic model with regard to male M. dolomieu nest site faithfulness.) No movement constraints were imposed in null models because the maximum distance between two nests in Pallette Lake is about 1,200 m and males in some populations are known to migrate 10,000 m from over-winter sites to spawn ( Fig. 2; [36]). ...
Background
Many animals appear to preferentially renest in proximity to a site they previously occupied. Evidence of nest fidelity is often inferred from a right skewed distribution of distances between the nests of individuals that breed in two consecutive reproduction episodes, where many individuals nest some arbitrarily close distance to their prior nest and others, in the extended right tail of the distribution, nest far from the nest they previously occupied. Because right skewed distributions of inter-nest distances can arise even when individuals choose nest locations randomly, however, such inferences are prone to error. The importance of null models—used to generate patterns of individual inter-nest distances by processes that do not involve site attachment—for inferences about site fidelity has been known for decades but is still often unappreciated or ignored.
Methods
The right skewed distributions of inter-nest distances observed in two earlier studies of male smallmouth bass (Micropterus dolomieu) suggest prima facie that males exhibit nest site fidelity between annual reproduction episodes, but patterns of inter-nest distances have yet to be compared to an adequate null model. Here, we evaluate the nest site fidelity of marked male M. dolomieu in a decade-long dataset, where we apply a randomization procedure based on the rencontre probability problem to generate null models. Eight observed distributions of individual, annual inter-nest distances are compared to a year-specific null model to determine whether random processes are sufficient to explain the observed distributions of inter-nest distances.
Results
Through contrasts between observed annual inter-nest distances and results derived from null models that imposed realistic constraints on behavior, we show that some males were undoubtedly nest-site faithful. To reinforce the utility of null models and to make these kinds of models more accessible, we also provide a supplemental tutorial. The tutorial illustrates how random site choices, subject to common ecological and behavioral constraints, and even how distance is measured, can produce patterns of inter-nest distances that falsely imply nest site fidelity, or a lack of fidelity. The R code needed to reproduce these null models is included. The inference errors evident in our examples generalize to other forms of site fidelity, such as the apparent patch fidelity of certain sea bird foragers.
Conclusions
The comparisons of observed distributions of inter-nest distances with those generated by null models imply that, as suggested in prior studies, male M. dolomieu indeed exhibit annual nest site fidelity. Procedures like those we apply are necessary first steps in analyses when distributions of distances between the nests of individuals in consecutive reproduction episodes are used to infer nest-site fidelity. Why male M. dolomieu are site faithful is a question yet to be answered.
... Parental behavior is costly and leads to a net loss of lean mass, as males rarely feed during this period (Gillooly and Baylis 1999). In northern populations, smallmouth bass activity ceases when water temperatures drop below 10°C, and over winter individuals are largely dormant, consume little food, and engage in limited movement (Hubbs and Bailey 1938, Munther 1970, Oliver et al. 1979; but see Lyons andKanehl 2002, Schreer andCooke 2002). The energetic cost of parental care in combination with the fact that smaller males may end winter with a proportionately larger energy deficit than larger males may explain the observation that larger males spawn earlier within a season than smaller males, as suggested by the relationships between size and reproductive timing found by Ridgway et al. (1991) and Lukas and Orth (1995). ...
The seasonal onset of reproduction is constrained in many systems by a need to first accumulate energetic reserves. Consequently, the observation that larger individuals reproduce earlier may be due to a negative relationship between size and mass‐specific basal metabolic rate that is shared across diverse taxa. However, an untested prediction of this hypothesis is that individuals should be metabolically efficient enough to escape energetic constraints above a certain size threshold. Seasonally reproducing species, such as temperate fishes, that must recover winter energy losses before reproduction and exhibit indeterminate growth are ideal models to test this prediction. We harness decade‐long behavioral data on parental male smallmouth bass, Micropterus dolomieu, to investigate contributions of energetic allometry to differences in reproductive timing. At the population level, peak seasonal reproductive timing (i.e. the median date on which eggs were found in nests each year) was negatively related to degree days – a measure of thermal energy experienced – before reproduction. At the individual level, degree days accumulated by males before reproduction was related to male size and condition in every year, but the impact of temperature on reproductive timing by the largest males was relaxed in most years. Additionally, we used our data to replicate the analyses of two previous studies of M. dolomieu populations and found virtually identical negative associations between male body size and degree days accumulated before reproduction. Our results suggest that in smallmouth bass the onset of seasonal reproduction is constrained by basal metabolic rate – as indicated by total length – and that large individuals can escape size‐associated energetic constraints. We reveal a more complicated relationship between size and reproductive timing than earlier studies, which may be relevant for many species. Knowledge of this relationship is critical to understanding how a changing climate will influence population dynamics of economically, ecologically and recreationally important species like M. dolomieu.
... Interestingly, past work on SMB eDNA detection conducted in 2017 in Miramichi Lake and a portion of the SWM River did find SMB DNA at two sites in the SWM River which were sampled in mid-October when temperatures were likely also near or below that 10 °C mark, which suggests that detections are still possible (O'Sullivan et al., 2020). Another possible reason for the non-detection of SMB DNA at the reference site on October 3 rd and 10 th , 2019 is the possibility that SMB might have relocated from McKiel Pond to a more suitable overwintering ground which is a known behavior of SMB (Baker, Warrenhicks, Gallagher, & Christensen, 1993;Ettinger-Dietzel, Dodd, Westhoff, & Siepker, 2016;Lyons & Kanehl, 2002) eDNA results from 2020 in the "McKiel stretch" were mostly similar to 2019 results, with relatively strong signals detected downstream of McKiel Pond, where a total of 86 fish were captured by boat electrofishing or angling activities in 2020. Interestingly, results for the reference site (i.e., site 5) sampled on September 10 th after the 86 fish had been caught and removed from McKiel Pond still produced a strong result indicating that quite a few fish were possibly still present in that area; although DNA persistence, from fish recently removed, based on DNA decay, geochemical adsorption, and sedimentation/resuspension processes cannot be completely disregarded as a potential source of the detected DNA (Harrison, Sunday, & Rogers, 2019). ...
Smallmouth Bass (Micropterus dolomieu), a non-native fish species in the Maritime Provinces, was first observed in Miramichi Lake (NB, Canada) in 2008. Since its discovery, Fisheries and Oceans Canada (DFO) has been leading containment, control, and monitoring activities with the support of non-government organizations and the Province of New Brunswick in an attempt to control the Smallmouth Bass (SMB) population within the lake. In August 2019, SMB was reported in the Southwest Miramichi River (SWM River), about 8 km downstream from Lake Brook, the outflow of Miramichi Lake. This led to a rapid mobilisation of resources by various partners and levels of government, including DFO, in an attempt to evaluate the spread and distribution of SMB within the SWM River system. Environmental DNA sampling in conjunction with species-specific qPCR testing was one of the methods used in both 2019 and 2020, as a means of gaining insight into the distribution of SMB. A total of 47 sites were sampled in both years and SMB DNA was found at multiple sites, with results classified as detected and suspected at sites downstream of McKiel Pond, where a total of 108 SMB were caught in 2019 and 2020. Results classified as inconclusive were also obtained upstream of Lake Brook, in McKiel Lake, and McKiel Brook, as well as a few other sites in the SWM River located between the outflow of McKiel Brook to Blackville. These inconclusive results warrant further investigation to confirm the presence of SMB in different portions of the watershed.
... They initiated movements to overwintering locations when mean daily water temperatures were around 17 to 23 ºC. Lyons and Kanehl (2002) and Langhurst and Schoenike (1990) reported spring spawning migrations by smallmouth bass in Wisconsin when water temperatures were between 10 and 16 ºC. As spawning concluded and winter neared, Langhurst and Schoenike (1990) observed smallmouth bass migrating to downstream overwintering areas when water temperatures began to fall below 16 ºC in autumn. ...
... Native to the east-central parts of the United States of America and two Canadian provinces, M. dolomieu is currently recognized as an invasive species in at least 12 countries worldwide, including South Africa (Loppnow et al., 2013). Although M. dolomieu has been described as a sedentary species when inhabiting riverine environments, establishing and guarding home ranges (Todd and Rabeni, 1989;Ridgway and Shuter, 1996), studies have observed remarkable fluctuations in dispersal behaviors when populations are subjected to environments with fluctuating habitat suitability, often leading to extensive movement in an attempt to colonize new habitats (Lyons and Kanehl, 2002;Hui and Richardson, 2017;Rubenson and Olden, 2017). Moreover, in a recent study by Diedericks et al. (2018a), significant population genetic structure was detected for M. dolomieu across the invaded South African range. ...
Dispersal is an essential life-history trait crucial to species persistence and diversification. This is particularly important in spatiotemporal fluctuating environments such as freshwater habitats, where species movement is confined to the dendritic network and wetted boundaries. To persist in such fluctuating environments, a species can modify, adaptively and plastically, its phenotypic variation to better match the environment or escape via directed dispersal to a more suitable habitat (i.e., matching habitat choice). We use the invasive smallmouth bass, Micropterus dolomieu, sampled at 10 km intervals, to assess the effect of directed dispersal on the fine scale genetic and phenotypic variation in populations of M. dolomieu along a river course. Gene flow was used as a proxy for dispersal. By comparing population genetic structure, morphological variation (of linear traits and geometric landmarks), and environmental heterogeneity, we discovered a clear correlation between environmental variation and morphological traits. Although isolation by distance seemed to have shaped the overall genetic pattern detected among the populations, the strong genetic structuring observed within the Ratel tributary appeared to be non-random. These results provide novel insights into the potential mechanisms promoting the spread and establishment of invasive species and the possible influence multiple introductions may have on fine scale genetic structuring.
... Only reaches separated by at least 3.2 rkm were considered independent replicates to be potentially selected at random. We used this spatial criterion because summer home ranges of smallmouth bass rarely exceed 2 rkm in these Minnesota streams (e.g., Altena 2003) and elsewhere (Lyons and Kanehl 2002;Ettinger-Dietzel et al. 2015). In practice, the two closest reaches we randomly sampled were 13 rkm apart. ...
Indices of biotic integrity (IBIs) are used to assess ecosystem health of streams and rivers. Streams and rivers with high IBI scores should support abundant and healthy populations of recreationally important sport fishes. However, the fundamental assumption that IBI scores and sport fish populations are associated needs to be examined. To verify this assumption, we tested associations between IBI scores and relative abundance of all sport fishes targeted by anglers, with emphasis on relative abundance of four size groups of smallmouth bass Micropterus dolomieu at 54 stream and river reaches in 2012 and 2013. We also tested for associations with smallmouth bass body condition and growth. A total of 13,708 fishes representing 85 species were captured including 11 sport fish species that included 571 smallmouth bass. We found that the maximum potential relative abundance of sport fishes and smallmouth bass size classes, as well as body condition of bass between 180 and 279 mm, could be predicted by IBI scores. We did not observe significant relationships with body condition of other bass size classes or with growth. Whereas abundance patterns were variable at reaches with higher IBI scores, abundance of larger, quality-sized sport fishes were more limited at reaches with IBI scores <30 that were classified as having poor biotic integrity. Maximum potential body condition was predicted to exceed 95, a condition value indicative of healthy fish, at IBI scores exceeding 50, reflective of reaches being classified as either fair, good, or excellent. These results confirm that management activities that enhance or maintain biotic integrity also support high-quality habitat for sport fish. While our findings support using IBIs as an indicator of the fishable goal specified in the United States Clean Water Act, managers should recognize that other factors not necessarily represented by the index can also limit sport fish populations.
... Smallmouth bass in riverine ecosystems are generally described as a sedentary species (Todd and Rabeni 1989) that establish home ranges and exhibit strong interannual homing tendencies (Ridgway and Shuter 1996). Populations subjected to large fluctuations of habitat suitability-such as range boundary populations-however, have exhibited dramatic differences in dispersal behaviors, undertaking long journeys to attempt colonization in novel habitats (Lyons and Kanehl 2002;Tabor et al. 2012). In the Pacific Northwest, evidence suggests that such large seasonal movements occur each year at the upstream extent of smallmouth bass' riverine range (Lawrence et al. 2012). ...
Studying the dynamics of species' borders can provide insight into the mechanisms limiting or promoting range expansion in response to environmental change. In the John Day River, Oregon (USA), rising stream temperatures are facilitating the upstream expansion of invasive smallmouth bass Micropterus dolomieu. Here, where smallmouth bass occupy the upstream limit of its thermal tolerance, we explore population structure and seasonal movement patterns to elucidate the environmental conditions and individual traits that define front edge (where individuals reside year-round) and leading edge (where individuals colonize, but may not establish) limits to its upstream distribution. Reporting on a multi-year, spatially extensive riverscape survey, our results show dramatic ebbs and flows of seasonal occupancies due to individual movement with an overall trend of upstream expansion. We revealed distinct front and leading edge invasion extents, each constrained by different ecological conditions. The front edge is largely constrained by the ability for juveniles to survive an overwinter starvation period, whereas the leading edge is associated with adult growth potential and seasonal hydrological conditions. We also found key morphological traits associated with more mobile individuals. By providing mechanistic insight into the factors that promote or limit range expansion of an invasive riverine species, our study enhances the ability to predict future range shifts and provides critical information to managers tasked with restricting further expansion.
... M. Reid, unpublished data). Our sampling occurred after the period of spring spawning migrations (Scott & Crossman, 1973) and before autumn movements to overwintering habitats (Lyons & Kanehl, 2000;Reid, 2004). Also, many of our detectability estimates were for small-bodied darters and minnows with small home ranges (Minns, 1995). ...
An increased electrofishing sampling effort will increase detection probabilities of riverine fishes. In this study, a repeat-sampling approach was used in small to medium-sized Ontario (Canada) rivers to estimate: (i) species-specific detection probabilities of freshwater fishes, (ii) the number of sampling events required to confidently detect species, and (iii) the power of timed-search surveys to detect future distribution (or occupancy) declines. Wadeable habitats at 36 sites were sampled with a backpack electrofisher on four separate dates during the summer low-flow period in 2013 and 2014. Forty-two species were collected, including three species of conservation concern (American eel Anguilla rostrata Lacépède, 1802, channel darter Percina copelandi Jordan, 1877, northern sunfish Lepomis peltastes Cope, 1870), and two recreationally important species (largemouth bass Micropterus salmoides Lacépède, 1802 and smallmouth bass Micropterus dolomieu Lacépède, 1802). A hierarchical Bayesian modelling approach was used to estimate detection probabilities and site occupancy for 18 species at four levels of effort: 250, 500, 750 and 1,000 s. In all cases, species detection was imperfect. Search effort had a positive effect on estimates of detection probability and site occupancy and the power to detect declines in future distribution. Detection probabilities ranged from 0.11 to 0.66 with an effort of 250 s, and 0.27 to 0.92 with an effort of 1,000 s. For 13 species, detection and power to detect changes in distribution were significantly improved by increasing sampling effort from 250 to 750 s or 1,000 s. For the channel darter and northern sunfish, three replicate sampling visits (of 750 or 1,000 s duration) are recommended for confident detection.
... The moderate to high relatedness in these sampled populations might indicate inbreeding, although significant loss of diversity does not seem to have occurred. Micropterus dolomieu appears to disperse the least of these three species, having a maximum lifetime dispersal reported as 10 km (Lyons & Kanehl, 2002). In comparison, P. flavescens may migrate up to 48 km (with the occasional individual travelling as far as 200 km; Rawson, 1980) and S. vitreus up to 300 km (Colby et al., 1979). ...
Genetic diversity and divergence patterns of smallmouth bass Micropterus dolomieu spawning groups are analysed across its northern native range with mtDNA cytochrome b gene sequences and eight unlinked nuclear DNA microsatellite loci. Results reveal high levels of genetic variability and significant differences in allelic representation among populations (mtDNA: mean ± s.e., HD = 0·50 ± 0·06, mean ± s.e., θST = 0·41 ± 0·02 and microsatellites: mean ± s.e. HO = 0·46 ± 0·03, mean ± s.e. θST = 0·25 ± 0·01). The distributions of 28 variant mtDNA haplotypes, which differ by an average of 3·94 nucleotides (range = 1–8), denote divergent representation among geographic areas. Microsatellite data support nine primary population groups, whose high self-assignment probabilities likewise display marked divergence. Genetic patterns demonstrate: (1) high genetic diversity in both genomes, (2) significant divergence among populations, probably resulting from natal site homing and low lifetime migration, (3) support for three post-glacial refugia that variously contributed to the current northern populations, which remain evident today despite waterway connectivity and (4) a weak yet significant genetic isolation by geographic distance pattern, indicating that other processes affect the differences among populations, such as territoriality and site fidelity.
... Global Fst entre poblaciones, calculados para un valor de AMOVA = 0.029 (P = 0.017, significancia estimada a partir de 10000 permutaciones). Lampsilis siliquoidea, bivalvo dulceacuícola de la familia Unionidae cuyo hospedador puede recorrer distancias que varían entre 6,5 y 75 km (Lyons & Kanehl 2002). ...
Genetic variability of a freshwater bivalve Diplodon chilensis from three Nahuelbuta lakes was described. Each lake shows geographic barriers and environmental characteristics as a consequence of geomorphologic and antropic events. Our results shows that only Lleu-Lleu lake was in Hardy-Weinberg equilibrium (P<0.05). All populations show gametic desequilibrium (P < 0.001), as an evidence of the species' life cycle. There are heterozygote deficiencies (Fis) in Laguna La Posada and Laguna Chica de San Pedro. Global Fst (0.027) and AMOVA test values for pooling subpopulation show non structured population, as an evidence of recent migration process.
... By comparison, L. fasciola has even greater dispersal capabilities, utilizing highly mobile black basses (Micropterus spp.) as its primary fish hosts. Basses can move more than 1 km in a single day (Lyons and Kanehl 2002). These primary fish hosts presumably have dispersal abilities that can be broadly categorized as low, medium, and high, respectively. ...
... We assumed YOY bass did not migrate downstream because we observed the same (2009) cohort in 2010 (now age 1 bass) at the upstream most nesting position (Lawrence, Olden & Torgersen 2012). Other studies have found that YOY and age 1 bass do not migrate (Lyons & Kanehl 2002). ...
Many ecologists have called for mechanism‐based investigations to identify the underlying controls on species distributions. Understanding these controls can be especially useful to construct robust predictions of how a species range may change in response to climate change or the extent to which a non‐native species may spread in novel environments.
Here, we link spatially intensive observations with mechanistic models to illustrate how physiology determines the upstream extent of the aquatic ectotherm smallmouth bass ( M icropterus dolomieu ) in two headwater rivers.
Our results demonstrate that as temperatures become increasingly cold across a downstream to upstream gradient, food consumption in age 0 bass becomes increasingly constrained, and as a result, these fish become growth limited. Sufficient first summer growth of age 0 bass is essential for overwinter survival because young bass must persist from energy reserves accumulated during the summer, and those reserves are determined by body size.
Our field data reveal the upstream extent of adult bass reproduction corresponds to a point in the downstream/upstream gradient where cold temperatures impair growth opportunities in young bass. This pattern was repeated in both study streams and explained why bass positioned nests twice as far upstream in the warm compared to the cold stream in the same basin. Placement of spawning nests by adult bass is likely subject to strong evolutionary selection in temperate systems: if bass spawn too far upstream, their young are unlikely to grow large enough to survive the winter. Consumption and growth in older bass (age 3–4) was far less sensitive to temperature. Based on these data, we suggest that temperature‐sensitive age 0 bass constrain the upstream distribution limits of bass within temperate streams.
In this study, we investigated how temperature‐dependent physiology changed through the life history of a species and, in doing so, identified a climate‐sensitive life‐history stage that likely sets the distributional limits of all other life‐history stages. We anticipate the framework developed here could be employed to identify how similar stage‐specific environmental sensitivity determines distribution in many other ectothermic species.
... By comparison, L. fasciola has even greater dispersal capabilities, utilizing highly mobile black basses (Micropterus spp.) as its primary fish hosts. Basses regularly can move more than 1 km in a single day (Lyons & Kanehl, 2002;VanArnum, Buynak & Ross, 2004). These primary fish hosts have dispersal abilities that can be broadly categorized as low (small darters), medium (logperch), and high (black basses), respectively. ...
Genetic variation was examined in two endangered mussel species, Epioblasma brevidens and Epioblasma capsaeformis, and in a non-listed species, Lampsilis fasciola, in the Clinch River, Tennessee, USA, by screening mitochondrial DNA (mtDNA) sequences and nuclear DNA microsatellites. Patterns of mtDNA polymorphism exhibited different trends in long-term population sizes for each species during the late Pleistocene and Holocene (∼20 000 ya to present); namely, E. brevidens has declined over time, E. capsaeformis has remained demographically stable, and L. fasciola has expanded. However, analyses using microsatellites did not exhibit similar trends, perhaps because homoplasy had eliminated long-term population signatures for the loci examined. For both marker types, long-term effective population size (Ne) was low in E. brevidens, intermediate in E. capsaeformis, and high in L. fasciola. Moderately diverged mtDNA lineages, perhaps indicative of secondary contact, were observed in E. brevidens and E. capsaeformis. Perhaps the most surprising result of this study was the high level of genetic variation observed at both mtDNA and microsatellite DNA markers for L. fasciola, variation seemingly contrary to the relatively small demes that currently reside in the Clinch River. However, the data are consistent with known demographic and life-history traits of these three mussel species and their fish hosts, namely that they each use hosts with different dispersal capabilities, ranging from low, moderate, and high, respectively. The low divergence of mtDNA sequence variation reported in this and other recent mussel studies indicates that considerable extant population genetic variation probably originated during the late Pleistocene and Holocene. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, ●●, ●●–●●.
... The moderate to high relatedness in these sampled populations might indicate inbreeding, although significant loss of diversity does not seem to have occurred. Micropterus dolomieu appears to disperse the least of these three species, having a maximum lifetime dispersal reported as 10 km (Lyons & Kanehl, 2002). In comparison, P. flavescens may migrate up to 48 km (with the occasional individual travelling as far as 200 km; Rawson, 1980) and S. vitreus up to 300 km (Colby et al., 1979). ...
Analysis of population genetic relationships reveals the signatures of ongoing processes such as spawning behavior and migration, and historical events such as vicariance and climate change. This study provides a dual genome analysis of population genetic patterns of spawning smallmouth bass across 13 locations-including all Great Lakes and the Mississippi, Ohio, St. Lawrence, and Hudson rivers -using eight nuclear DNA microsatellite loci and mtDNA cytochrome b sequences. Null hypotheses are (1) genetic variation is not significantly partitioned among watersheds, lakes, rivers, and basins and (2) there is not a significant difference between mitochondrial and nuclear DNA patterns. Results discern genetic demarcations across the range, and pronounced differences even among closely spaced riverine sites. Sampling sites contain a substantial proportion of full-sibling adults, suggesting natal site fidelity and relatively low dispersal. Population genetic origins trace to recolonization patterns from glacial refugia, which have been maintained through present day. Relationships follow a broadscale genetic isolation by geographical distance pattern, but those within lakes and proximate river sites do not. The latter appear influenced by homing and site fidelity.
... By comparing the early and late summer surveys, it is clear that bass moved upstream and the overall numbers of bass increased in the survey extent. Upstream migrations of smallmouth bass have been observed in other river systems, and these movements may be motivated by bass seeking river segments suitable for spawning (Lyons & Kanehl, 2002) or may be the result of density-dependent processes (DeAngelis, Godbout & Shuter, 1991). ...
1. Smallmouth bass ( Micropterus dolomieu ) have been widely introduced to fresh waters throughout the world to promote recreational fishing opportunities. In the Pacific Northwest (U.S.A.), upstream range expansions of predatory bass, especially into subyearling salmon‐rearing grounds, are of increasing conservation concern, yet have received little scientific inquiry. Understanding the habitat characteristics that influence bass distribution and the timing and extent of bass and salmon overlap will facilitate the development of management strategies that mitigate potential ecological impacts of bass.
2. We employed a spatially continuous sampling design to determine the extent of bass and subyearling Chinook salmon ( Oncorhynchus tshawytscha ) sympatry in the North Fork John Day River (NFJDR), a free‐flowing river system in the Columbia River Basin that contains an upstream expanding population of non‐native bass. Extensive (i.e. 53 km) surveys were conducted over 2 years and during an early and late summer period of each year, because these seasons provide a strong contrast in the river’s water temperature and flow condition. Classification and regression trees were applied to determine the primary habitat correlates of bass abundance at reach and channel‐unit scales.
3. Our study revealed that bass seasonally occupy up to 22% of the length of the mainstem NFJDR where subyearling Chinook salmon occur, and the primary period of sympatry between these species was in the early summer and not during peak water temperatures in late summer. Where these species co‐occurred, bass occupied 60–76% of channel units used by subyearling Chinook salmon in the early summer and 28–46% of the channel units they occupied in the late summer. Because these rearing salmon were well below the gape limitation of bass, this overlap could result in either direct predation or sublethal effects of bass on subyearling Chinook salmon. The upstream extent of bass increased 10–23 km (2009 and 2010, respectively) as stream temperatures seasonally warmed, but subyearling Chinook salmon were also found farther upstream during this time.
4. Our multiscale analysis suggests that bass were selecting habitat based on antecedent thermal history at a broad scale, and if satisfactory temperature conditions were met, mesoscale habitat features (i.e. channel‐unit type and depth) played an additional role in determining bass abundance. The upstream extent of bass in the late summer corresponded to a high‐gradient geomorphic discontinuity in the NFJDR, which probably hindered further upstream movements of bass. The habitat determinants and upstream extent of bass were largely consistent across years, despite marked differences in the magnitude and timing of spring peak flows prior to bass spawning.
5. The overriding influence of water temperature on smallmouth bass distribution suggests that managers may be able limit future upstream range expansions of bass into salmon‐rearing habitat by concentrating on restoration activities that mitigate climate‐ or land‐use‐related stream warming. These management activities could be prioritised to capitalise on survival bottlenecks in the life history of bass and spatially focused on landscape knick points such as high‐gradient discontinuities to discourage further upstream movements of bass.
... Fish were collected from 50 sites (see Bean 2012 for more detailed site information) among 12 river subbasins (Table 1) encompassing the range of the Guadalupe Bass in the Lampasas, San Gabriel, Concho, San Saba, Llano, Pedernales, Colorado, Guadalupe, and Medina, Nueces, Frio, and Sabinal subbasins (Figure 1). Based on the proximity of sites with subbasins, population genetic structuring largely at the subbasin level (Bean 2012), and the movement of Guadalupe Bass (Perkin et al. 2010) and Smallmouth Bass (Lyons and Kanehl 2002), samples were grouped by subbasin for analyses. Fish were collected using a combination of sampling gears, including backpack electrofishing, boat electrofishing, seining, and angling. ...
The stocking of fishes outside of their native range for the purpose of sport fisheries can lead to secondary contact and introgression between species that were historically allopatrically distributed. Smallmouth Bass Micropterus dolomieu were introduced within the range of Guadalupe Bass M. treculii in central Texas and introgressive hybridization subsequently occurred. One recent survey of temporal changes in introgression in the Blanco River found that introgression had increased and that Guadalupe Bass had been extirpated. Thus, a survey of changes in introgression across the range of the Guadalupe Bass was conducted in 12 subbasins in the Brazos, Colorado, Guadalupe–San Antonio, and Nueces drainages in Texas using 15 microsatellite loci. The results indicate that introgression is now occurring in four subbasins but no longer occurring in the Lampasas and San Gabriel rivers, where rates were previously 6% and 46%, respectively. Additionally, we found no evidence that stocking of hatchery-reared individuals in the Guadalupe and Nueces rivers has led to severely depressed genetic variation. The variable success of restoration efforts to prevent extirpation of the Guadalupe Bass suggests that protection of the remaining nonintrogressed populations should be a priority for the conservation of this species.Received April 24, 2012; accepted December 9, 2012
... Pagination not final (cite DOI) / Pagination provisoire (citer le DOI) largemouth bass. Most of these studies found that in the summer, largemouth bass (Micropterus salmoides) and smallmouth bass (Micropterus dolomieu) moved over small spatial scales of ≤1.6 km (Bain and Boltz 1992;Lyons and Kanehl 2002;Ridgway 2002;Hunter and Maceina 2008). Maximum distances recorded for Micropterus species in those studies ranged from 1.3 to tens of kilometres (Funk 1957;Reynolds 1965;Ridgway 2002). ...
Spatial heterogeneity in habitat conditions within a landscape should influence degree of movement of species between natural and artificial environments. For wetland landscapes, this functional connectivity was predicted to emerge from the influence of spatiotemporal patterns of depth on permeability of habitat edges and distance and directedness of cross-habitat dispersal. We quantified how connectivity between canals and marshes of the Florida Everglades varies with species and landscape patterns bordering canals by using radio telemetry to measure movement of a native (Florida largemouth bass, Micropterus salmoides floridanus) and a nonnative species (Mayan cichlid, Cichlasoma urophthalmus) common to canals. Both species moved similar distances inside canal networks, but Mayan cichlids dispersed outside of canals more frequently, at shallower conditions, and over greater distances than Florida largemouth bass. As topographic relief increased in marshes bordering canals, dispersal between these habitats decreased in distance and became more directed, with Florida largemouth bass sensitive to depth variability at a smaller spatial scale than Mayan cichlids. The way fish traits interact with submerged landscape structure to influence connectivity can serve as a basis for predicting potential impacts of artificial habitats that arise from dispersal outside their borders.
... Thermally, Smallmouth Bass have been classified as a warm water species (Lyons et al., 2009;Lyons, 2011). Some riverine populations have complex migratory behavior related to over-wintering habitat (Lyons and Kanehl, 2002). As such, an appropriate Smallmouth Bass classification scheme should consider the possible effects of location, river size, substrate, productivity, and water temperature. ...
Smallmouth Bass (Micropterus dolomieu) is an important sportfish and has been suggested as a restoration target species in degraded aquatic environments such as “Areas of Concern” in the Great Lakes basin. Determining expected relative densities of fish and wildlife populations, such as Smallmouth Bass, in least-impacted situations is central to developing effective monitoring programs, assessing the level of relative impairment, determining appropriate restoration goals, and evaluating the efficacy of restoration efforts. We tested a straightforward classification scheme of Smallmouth Bass populations in least impacted non-wadeable rivers in Wisconsin based on parameters related to substrate and geographic location as both variables have been associated with relative Smallmouth Bass density. Coarse-substrate rivers tended to have higher Smallmouth Bass catch per effort values than fine-substrate rivers and southern rivers tended to have higher catch per effort values than northern rivers in Wisconsin. We used the expected Smallmouth Bass relative density estimates to assess the level of impairment of Smallmouth Bass populations in three Areas of Concern in Wisconsin (Milwaukee River and Estuary, Sheboygan River and Estuary, and the Fox River and Green Bay). We found that Smallmouth Bass catch per effort values were significantly higher in Areas of Concern than both the minimum and 25th percentile values for least-impacted rivers and were not significantly different from the median least-impacted values. Based on abundance, it does not appear that Smallmouth Bass populations are particularly impaired in these three Areas of Concern.
... Global Fst entre poblaciones, calculados para un valor de AMOVA = 0.029 (P = 0.017, significancia estimada a partir de 10000 permutaciones). Lampsilis siliquoidea, bivalvo dulceacuícola de la familia Unionidae cuyo hospedador puede recorrer distancias que varían entre 6,5 y 75 km (Lyons & Kanehl 2002). ...
Genetic variability of a freshwater bivalve Diplodon chilensis from three Nahuelbuta lakes was described. Each lake shows geographic barriere and environmental characteristics as a consequence of geomorphologic and antropic events. Our results shows that only Lleu-Lleu lake was in Hardy-Weinberg equilibrium (P<0.05). All populations show gametic desequilibrium (P < 0.001), as an evidence of the species' life cycle. There are heterozygote deficiencies (Fis) in Laguna La Posada and Laguna Chica de San Pedro. Global Fst (0.027) and AMOVA test values for pooling subpopulation show non structured population, as an evidence of recent migration process.
... Approximately one-third of individuals moved to different channel units between seasons. This suggests these populations move more than other Ozark populations (Todd and Rabeni 1989), supporting the hypothesis that the degree of movement is population specific (Lyons and Kanehl 2002). In one reach in Baron Fork Creek, smallmouth bass moved into a specific backwater and adjacent habitats during winter, presumably as a thermal refuge. ...
The spatial and temporal dynamics of stream habitat and fish populations are important considerations for the conservation and management of stream fishes. We determined how stream habitat and populations of smallmouth bass Micropterus dolomieu varied among third-order to fifth-order stream reaches in two regional streams in eastern Oklahoma from 2003 to 2005. Eastern Oklahoma represents the southwestern edge of the species' range and is where the Oklahoma Department of Wildlife Conservation focuses its stream habitat management efforts. Water temperature, streamflow, and habitat differed between Baron Fork Creek (northeast) and the Glover River (southeast) and changed longitudinally within each stream. Smallmouth bass abundance was highest downstream in Baron Fork Creek and lowest downstream in the Glover River. Recruitment was poor and variable in the upstream reaches of both streams and was strong and stable downstream in Baron Fork Creek. The survival of age-1 and older smallmouth bass was higher in Baron Fork Creek than in the Glover River. The relative weights of smallmouth bass were higher in Baron Fork Creek than in the Glover River upstream, and they decreased downstream in Baron Fork Creek. Growth was highest from summer to fall, and relative weights were lowest in spring and highest in summer. Survival was typically lowest from summer to fall. Movement among channel units was highest from fall to winter, and there was evidence that older individuals moved more often. Smallmouth bass used different habitats for overwintering versus spring spawning, and they used most deep habitats in summer and fall. Integrating population dynamics with stream habitat helped to identify habitat management strategies that can best enhance smallmouth bass populations at the edge of their native distribution, where they provide important recreational fishing opportunities to anglers.
... Individual flathead catfish show movements of tens or hundreds of kilometers (Vokoun & Rabeni, 2005), while both darters and sunfishes move <1 km (Freeman, 1995). Smallmouth bass, Micropterus dolomieui (Lacepéde), another centrarchid host for L. siliquoidea, disperse an average of 6.5 km in streams and individuals occasionally migrate up to 75 km during severe winters (Lyons & Kanehl, 2002). Darters are typically considered a minimally dispersing group with movements of metres (Scalet, 1973), and limited dispersal by darter hosts has been implicated as a factor leading to patchy distribution and poor colonisation ability of the endangered mussel Alasmidonta heterodon (I. ...
1. Unionid mussels are highly threatened, but little is known about genetic structure in populations of these organisms. We used allozyme electrophoresis to examine partitioning of genetic variation in three locally abundant and widely distributed species of mussels from a catchment in Ohio.
2. Within-population variation was similar to that previously reported for freshwater mussels, but genotype frequencies exhibited heterozygote deficiencies in many instances. All three species exhibited significant among-population variation. Evidence of isolation-by-distance was found in Elliptio dilatata and Ptychobranchus fasciolaris, while Lampsilis siliquoidea showed no geographical pattern of among-population variation.
3. Our results suggest that the isolating effects of genetic drift were greater in L. siliquoidea than in the other species. Differentiation of populations occurred at a much smaller spatial scale than has previously been found in freshwater mussels. Differences among species may reflect differences in the dispersal abilities of fishes that serve as hosts for the glochidia larvae of mussels.
4. Based on our results, we hypothesise that species of mussels that are common to large rivers exhibit relatively large amounts of within-population genetic variation and little differentiation over large geographical distances. Conversely, species typical of small streams show lower within-population genetic variation and populations will be more isolated. If this hypothesis can be supported, it may prove useful in the design of conservation strategies that maintain the genetic structure of target species.
... Bivalves such as Amblema plicata (Unionidae) have a comparatively weak population structure that indicates a large effective population size and/or high dispersal (Elderkin et al. 2007). Potential host fishes of A. plicata such as smallmouth bass Micropterus dolomeiu Lacepède (Centrarchidae) move up to 75 km (Lyons and Kanehl 2002). River fragmentation by dams for example affects the migration of host fishes (Watters 1996;Dean et al. 2002, and references therein) and thus threatens Unionidae because it reduces both habitat quality and dispersal. ...
Molluscs are the proverbial examples of slow movement. In this review, dispersal distances and speed were assessed from literature
data. Active upstream movement can occur both individually and in groups; and depends on traits such as size, sex and reproductive
status, and on external factors such as flow velocity, temperature, sediment structure, and food availability. The potential
for active dispersal follows the sequence Pulmonata≥Prosobranchia>Bivalvia, although data for Pulmonata originated from
short-term experiments that likely overestimated dispersal capabilities. Active upstream movement may be 0.3 to 1.0km per
year for most snails and is probably well below 0.1km per year for bivalves. Natural passive upstream dispersal increases
the range 10-fold (snails) to 100-fold (bivalves), and anthropogenic vectors can increase upstream dispersal more than 100-fold
(snails) to 1000-fold (bivalves). Three km seems to be the maximal within-stream distance at which many species display regular
population mixing, and at which re-colonisation or successful restoration can be expected within 3–10years. Lateral dispersal
between unconnected water bodies is passive and mostly known from observational reports, but potential distances depend on
vectors, climate and geomorphology. In general, active dispersal seems insufficient to furnish a compensatory mechanism, e.g.,
for the rate of projected climate change. We provide an overview on dispersal strategies in the light of applied issues. More
rigorous field surveys and an integration of different approaches (such as mark-recapture, genetic) to quantify distances
and probabilities of lateral dispersal are needed to predict species distributions across space and time.
KeywordsBiological invasion–Dispersal–Global change–Mollusca–Species distribution modelling (SDM)–Vector
Determining the genetic diversity of unionid populations is important for the preservation of the species and ecosystems in which they reside. The Yellow lampmussel, Lampsilis cariosa, is an endangered unionid found along the Atlantic Slope drainages in the United States and Canada. Along with many other North American unionid species, L. cariosa populations are declining. In order to enhance conservation efforts, the genetic structure and diversity of current populations must be examined. A sample of 178 individuals of L. cariosa from 20 populations in the Susquehanna and Delaware River drainages, and two different river populations in Maine were genotyped at the mitochondrial cytochrome oxidase subunit one (COI) gene and seven microsatellite loci. Haplotype genetic diversity for L. cariosa was low, while nucleotide diversity was high. Analysis of mtDNA showed significant population structure but lower than that of other mussel species. Our results indicate past gene flow among populations found in the Susquehanna and Delaware drainages with recent demographic expansion. As an endangered species with currently small population sizes, conservation efforts for L. cariosa should focus on protecting genetic diversity by preserving the largest populations in different drainages.
The family Centrarchidae includes about 34 species, which all have their native range
in North America. In the Netherlands the most ill famous member is Lepomis
gibbosus. This in the Netherlands invasive species is the only member of the family
with established populations. These populations can be found all over the Netherlands
and the species seems to be still expanding. Its negative image is caused by its
presence in many isolated water bodies where it has a strong negative impact on the
fauna, including rare amphibians such as the common spadefoot (Pelobates fuscus)
and the European tree frog (Hyla arborea). Because of this impact a wholesaler has
decided stop selling this species in 2010.
In this study it is shown that another nine species of Centrarchidae should be
considered to be potentially invasive. They are all at least available for export in North
America and have a high probability of establishment based on their thermal biology:
A. rupestris, P. annularis, P. nigromaculatus, L. cyanellus, L. macrochirus, L.
megalotis s.l. (L. megalotis s.s. & L. peltastes), M. dolomieu & M. salmoides. When
considering possible climate change in the period 1990-2050 L. auritus should be
included in this list. These species are all flexible in their habitat preferences and are
likely to find suitable habitats in most regions in the Netherlands. With these
centrarchids known to be good dispersers, it is likely that they will spread relatively
easily after establishing reasonable populations. The family Elassomatidae, which is
also reviewed as they might be a potential substitute for centrarchids in trade, is
considered to be of no risk as they are unlikely to survive Dutch winters.
Like L.gibbosus also other Centrarchidae are likely to affect ecosystems mainly by
predation (amphibians, smaller fish species, damselflies, etc.) and competition with
other predatory fish. Especially ecosystems, lacking comparable native predatory fish
species prior to the establishment of such an exotic centrarchid, are susceptible to
significant ecological impact. Centrarchidae have not been reported to be vectors for
parasites or diseases of special concern.
The establishment of larger centrarchid species will have a small, positive social and
economic impact to commercial fisheries, the angling society and related business.
When established, centrarchid populations can in most instances only be eradicated
with rigorous measures like dewatering or the use of piscicides. Obviously, the
prevention of entries and further spread reduces the need for such actions. The major
components of prevention are banning of potential invasive species from trade and
educating the public about the impact of centrarchids.
Limited information exists on 24-hr movement and habitat selection patterns of stream
dwelling smallmouth bass, Micropterus dolomieu. We monitored the 24-hr movement
patterns of smallmouth bass in an Ozark river during three seasons: summer, autumn,
and winter. During each season, fish were located every two hours throughout a 24-hr
period; habitat data and water depth were collected at each fish location. Four random
points representing available locations around each fish location were generated in
ArcGIS. Habitat and depth data were collected at each of these points, and discrete
choice models were fit to the data to predict habitat and depth selection by smallmouth
bass. No significant differences in movement across seasons or time of day were evident,
although the greatest observed displacement within a 2-hr tracking period occurred
during the winter, with one bass moving over 630 m. Across all three seasons, water
depth and habitat type were strong predictors of bass locations. Throughout our study,
water depths used by smallmouth bass ranged from 0.6 to 3.7 m. Although depth of
water used by fish did not differ by time of day, fish used the deeper waters of Big
Spring during the winter and intermediate depths during the summer and autumn.
Smallmouth bass utilized several habitat types; however, bass selected boulders more
frequently in all seasons than any other available habitat type. Our work provides
additional insight into smallmouth bass behavior that will help guide future management.
We estimated how much recruits, survivors, and immigrants contributed to population size in six reaches in southeast Minnesota. Recruitment was determined from population estimates made in September. Survival and emigration were estimated from mark and recapture of individually PIT-tagged brown trout, representing three ontogenetic groups (age 0, age 1 and 2 adults, age 3+ large adults) across reaches and four seasons (see associated Poster). Immigration was calculated as one minus emigration. Recruitment varied among the six reaches and three years of this study (range 0-1,292/km) and was consistently low in all reaches in 2007 due to flooding. Survival and emigration varied by reach or season depending on ontogenetic group (see associated poster). For age 0 trout, immigrants were estimated to contribute 50% or more of age-0 abundance in three of the six study reaches. In the other three reaches, immigrants contributed 0% to 35%. Recruitment (i.e., aging of age 0 trout to age 1) was estimated to contribute more than 50% of age 1 and 2 trout to most reaches, especially in 2006-2007 as a result of a large 2006 year class. Survival was estimated to account for 50% or more of the predicted abundance of age 3+ trout in almost all reaches. Although variable, broad patterns suggest that age-0 populations are dependent on immigration, age 1 and 2 adults on recruitment, and age 3+ trout on survival.
We assessed recruitment, survival, emigration, and immigration of brown trout Salmo trutta in six interconnected stream reaches to quantitatively estimate how much immigrants contributed to population size in reaches in southeastern Minnesota. We also examined the influence of reach and season on estimates of survival and emigration via mark and recapture of individual trout representing three groups (age-0 juveniles, age-1 and age-2 adults, and age-3+ large adults). Immigration was calculated as 1 minus emigration. Recruitment varied among the six reaches and 3 years of this study (range, 0–1,292 fish/km). Survival of the age-0 group and that comprising ages 1 and 2 varied by season but not reach. Survival was highest in winter for both groups but lowest in spring for age-0 trout and in fall for age-1 and age -2 trout. Emigration varied by season for age-0 trout but by reach for trout of ages 1 and 2. For age-3+ trout, survival and emigration only varied by reach. Survival was highest and emigration was lowest in reaches with the most cover, including deep pools. From these demographic characteristics we estimated the proportions of the population that consisted of brown trout that had survived within a reach, recruited into it, or immigrated into it from some other reach. Immigration was predicted to contribute the most for the youngest age-group (35% or more of the predicted abundance of age-0 trout in most reaches) and is probably important for genetic purposes or to bolster population units in adjacent reaches. Our results for adult brown trout suggest that within-reach recruitment and survival contribute a larger proportion of trout to population units in many reaches than do immigrants. This confirms the appropriateness of current management approaches and suggests that maintenance of the exceptional recreational brown trout fishery in southeastern Minnesota is at least solidly dependent on factors promoting recruitment and survival within most managed stream reaches.Received November 20, 2010; accepted June 9, 2011
Stream-dwelling fish face highly-variable environmental conditions from fall to winter due to fluctuations in water temperatures, discharge, and ice conditions. We provide an in-depth description of the interactions between these complex environmental conditions and behaviors of stream-dwelling salmonids during winter. Fisheries managers should be aware of the conditions that fish confront during winter in order to make appropriate management decisions. Diverse habitats, including deep pools with low water velocities, coarse rock substrate, and abundant cover, as well as side channels and backwaters, aid in the survival of overwintering fish. The inflow of relatively warm groundwater into the water column can be an important factor affecting winter habitat. Considering the length of winter and the vulnerability of fish during winter, a broad understanding of winter ice process and their effects on stream dwelling fish can aid in the preservation and improvement of winter habitats.
Fish movement may vary across a wide array of aquatic ecosystems and may be related to the overall size of the system inhabited. We investigated movement of smallmouth bass in Lake Michigan because this information is lacking for larger systems. A total of 16 smallmouth bass were surgically implanted with ultrasonic transmitters within the Beaver Archipelago, northern Lake Michigan. During 2007–2008, a maximum of one location per individual was recorded daily during three specific tracking periods – pre-spawn, spawning, and post-spawn – to determine diurnal movement patterns. Movement was evaluated as site fidelity, minimum displacement rate, maximum excursion rate, and distance from shore. Smallmouth bass exhibited greater maximum excursion rates during the spawn period compared to pre-spawn. Movement rates did not differ between tracking periods; however, movement rates were greater during the spawn period in 2007 than 2008. Both sexes moved further offshore to deeper water during post-spawn, but females were located further offshore than males during this period. Annual site fidelity was more evident during post-spawn than during spawning for both sexes. Two smallmouth bass emigrated outside of the Archipelago, suggesting this population may be more “open” in terms of individuals moving throughout northern Lake Michigan than previously thought. These results indicate smallmouth bass may move greater distances in larger aquatic systems and therefore larger management units (in terms of total area) should be established in Lake Michigan to account for these greater excursion distances.
Diverse freshwater lacustrine fishes enter tributaries to spawn, but resident riverine members may also occupy these same tributaries. While mark-recapture and biotelemetry studies suggest reproductive isolation between such populations, the assertion has rarely been tested genetically. To address this question, Micropterus dolomieu (Smallmouth Bass) from the southern shoreline of Lake Erie were compared genetically to bass in adjacent tributaries. Results from mitochondrial DNA sequences support the hypothesis that lacustrine and riverine populations segregate. Furthermore, divergences among tributary populations were often as large as those divergences between lacustrine and riverine bass, suggesting that each river population may become genetically distinct.
We evaluated characteristics of smallmouth bass (Micropterus dolomieu) and shadow bass (Ambloplites ariommus) populations in a small, northeastern Oklahoma Ozark stream from February 2000 to March 2003 to evaluate potential effects of rainbow trout (Oncorhynchus mykiss) introduction on these species. We experimentally stocked rainbow trout into the stream from November 2000 to March 2001 and November 2001 to March 2002. Mark-recapture and telemetry data showed patterns of limited movement among pool habitats by both bass species, and presence of rainbow trout in Brush Creek did not appear to influence movement patterns. We documented recruitment by smallmouth and shadow bass during our study, indicating that rainbow trout introduction did not inhibit spawning. Mean relative weight (W,r) of smallmouth bass ranged from 77—80, and we did not detect differences in relative weight among pre-stocking, the first year of stocking, and the second year of stocking. It appears that important population characteristics of these two species in our study stream were not negatively impacted by rainbow trout introduction.
The southwestern edge of the natural range of smallmouth bass Micropterus dolomieu contains streams that become disconnected pools during summer primarily owing to hydrogeologic conditions, including high evapotranspiration rates. These conditions may complicate fisheries management by affecting fish behavior or mortality rates. The objectives of this study were to characterize summer habitat use by smallmouth bass, estimate the changes in the extent of available habitat, describe summer movement patterns, and estimate summer survival rates. Radio transmitters were implanted into 60 smallmouth bass during May 2006, and the fish were tracked until October in the forks of the Illinois Bayou, which drains a portion of the Ozark National Forest. Habitat characteristics were measured as the summer progressed, and during this time most riffle–run habitat dried completely, resulting in a series of disconnected pools. The decreases in wetted area exceeded 55% in certain 2-km study reaches; however, smallmouth bass were consistently found at a median depth of 0.80 m. Boulder habitat was preferred when it was available; however, cobble, gravel, and bedrock substrates were also used. By July, velocity was below detection levels and water temperature occasionally exceeded 30°C. The average distance moved by smallmouth bass was 270 m in May, decreasing to 54 m by July. The distances moved were greater on average but more variable in streams with larger losses of wetted area, as fish moved away from drying areas. The survival rate was lowest in the stream most accessible to anglers. Dryness appeared to increase mortality, as survival estimates were lower than expected from published studies of streams with continuous summer flow. The effective management of fisheries under such hydrologic conditions may require preserving continuous surface flow and the quality of remnant pools as well as implementing more restrictive harvest regulations in summer.
Over 70% of North American freshwater mussel species (families Unionidae and Margaritiferidae) are listed as threatened or
endangered. Knowledge of the genetic structure of target species is essential for the development of effective conservation
plans. Because Ambelma plicata is a common species, its population genetic structure is likely to be relatively intact, making it a logical model species
for investigations of freshwater mussel population genetics. Using mtDNA and allozymes, we determined the genotypes of 170+
individuals in each of three distinct drainages: Lake Erie, Ohio River, and the Lower Mississippi River. Overall, within-population
variation increased significantly from north to south, with unique haplotypes and allele frequencies in the Kiamichi River
(Lower Mississippi River drainage). Genetic diversity was relatively low in the Strawberry River (Lower Mississippi River
drainage), and in the Lake Erie drainage. We calculated significant among-population structure using both molecular markers
(A.p. Φst=0.15, θst=0.12). Using a hierarchical approach, we found low genetic structure among rivers and drainages separated by large geographic
distances, indicating high effective population size and/or highly vagile fish hosts for this species. Genetic structure in
the Lake Erie drainage was similar to that in the Ohio River, and indicates that northern populations were founded from at
least two glacial refugia following the Pleistocene. Conservation of genetic diversity in Amblema plicata and other mussel species with similar genetic structure should focus on protection of a number of individual populations,
especially those in southern rivers.
Abundance and distributions for five taxonomic groups of fishes were recorded by underwater surveys in two headwater streams of the Little Missouri River System in the Ouachita Mountains of Arkansas. Observations were made from February to November 1993. Two components of the native fish assemblage were discernible: year-round residents and spring-to-fall residents. Creek chub (Semotilus atromaculatus) and central stoneroller (Campostoma anomalum) appeared to be year-around residents. Two types of spring-to-fall residents were recognized: species represented by juveniles only, and species represented by all age classes. Smallmouth bass (Micropterus dolomieu) observed in the creeks were primarily juveniles. Longear sunfish (Lepomis megalotis) and several shiner species (Cyprinidae) were observed breeding in the creeks.
Cellular temperature compensation of green sunfish Lepomis cyanellus, a species active in cold water, was compared to that of the cofamilial smallmouth bass Micropterus dolo-mieui, a species quiescent in cold water. It was hypothesized that there would be a correlation between degree of cellular temperature compensation and degree of coldwater activity for these two centrarchids. Fishes were acclimated to 5, 15, or 25°C in the laboratory for 10 weeks. In both species, red muscle citrate synthase activity was elevated in fish acclimated to 5 and 15°C relative to those at 25°C. Red muscle area per body cross-sectional area was elevated in both species acclimated to 5°C relative to those at 25°C. Heart ventricle citrate synthase activity and ventricular weight showed temperature compensation in the smallmouth bass but not in the green sunfish. These data do not suggest a correlation between degree of cellular temperature compensation and degree of coldwater activity for these two centrarchids. Winter quiescence of smallmouth bass is almost certainly facultative, and cellular temperature compensation may commonly occur in facultatively quiescent ectotherms.
Forty radio frequency transmitters and 120 dart tags were used to monitor movements of adult smallmouth bass (Micropterus dolomieui) in relation to water level fluctuations in the Columbia River at Hanford, Washington, in 1976 and 1977. Bass movement appeared to be influenced by water level fluctuations, water depth, current, and available forage organisms. Spawning success of adult bass was estimated at three study areas: White Bluffs, Hanford, and F Area sloughs. Spawning was adversely influenced by high river levels, which flooded nest sites with cool water and caused other perturbations. Spawning success was relatively poor in 1976, a high-water year, and relatively good in 1977, a low-water year. Loss of juvenile bass due to entrapment, predation, thermal and oxygen stress, and desiccation was monitored during the summer in several temporary ponds created by fluctuating river flows.
The movement and distribution of smallmouth bass, Micropterus dolomieui, were studied in the Snake River, a large western river, prior to impoundment. A tag and recovery program was designed to assess interpool movement. Smallmouth bass were collected by angling and electrofishing. Primacord, a detonating fuse, was used to assess distribution during late fall and winter. Underwater observations were made with SCUBA apparatus. Bass behavior was studied in the laboratory and dealt principally with temperature effects, light intensity and substrate.Only 8% of the tagged fish recaptured were taken by anglers; the remaining 92% were taken by electrofishing. Ninety-nine (76%) of the recovered fish free at least 7 days were found in the same pool or defined location in which they were tagged, while 22 of the 31 fish recovered outside the pool in which they were marked had moved less than 1200 m (1,312 yds). A few moved several kilometers upstream or downstream from the release point. There was no significant seasonal variation in numbers of fish moving in different seasons, although there seemed to be slightly more movement in spring and less in summer than the mean movement. The distances moved at various seasons were not significantly different, nor was the seasonal direction of movement.A preference for broken rock substrate was indicated in the river by high fish densities over this type of substrate. Few smallmouth bass were found over a solid rock substrate, and none was observed over sand.In late fall, as water temperatures dropped below 15.5 C (60 F), smallmouth bass could not be located by electrofishing in water less than 2.3 m (8 ft) deep, but were found in still rocky pools at least 3.6 m (13 ft) deep by detonating primacord on the pool bottoms.The distribution of smallmouth bass within a pool changed during the 24-hour day. Smallmouth bass observed in early morning were all near the edge of the current. When the location of the edge of the current changed due to fluctuating water level, the bass shifted to the new position of current edge. In early morning no bass were observed more than a few meters from the edge of the current. Nocturnal positions of smallmouth bass were on or beneath a broken rock substrate in still water. When beneath the substrate bass faced toward an exit. No movement by smallmouth bass was observed in the river at night.In the laboratory smallmouth bass fed during the day and went on or beneath the substrate during darkness. This change in position took place at dusk. Some individuals appeared to defend night locations and rock substrate appeared preferable to sand. Fish came out from beneath the substrate at low light intensities in the morning. Activity decreased with temperature. Most of the fish remained beneath the substrate while temperatures were less than 6.7 C (44 F) and came from beneath the substrate when the water temperature reached 7.8 C (46 F).
This paper presents the results of the first attempt to estimate and identify factors influencing individual reproductive success in a fish species, under natural conditions, after the progeny have dispersed from their site of origin. Using family-specific DNA fingerprints, the reproductive success of male smallmouth bass in Lake Opeongo, Ontario was estimated and evaluated at the point when their offspring were fall young-of-the-year (YOY). For the 1992 spring spawning season, we generated family-specific fingerprints using DNA of fry captured from 116 nests in Jones Bay. In the fall of the same year, 283 YOY were captured by electrofishing along the shoreline of the study area. Using DNA obtained from fin tissue, a fingerprint was generated for each fall YOY and compared to the family fingerprints to determine the family of origin. Males were considered successful if at least one of their offspring survived to the fall YOY stage. Although 27.7% of all males who acquired eggs (N = 57) had at least one offspring surviving to the fall YOY stage, only 5.4% of all spawning males (N = 11) produced 54.7% of the total number of fall YOY captured. If recruitment frequently depends on the success of such a small number of males, then population abundance will be extremely vulnerable to adverse natural and anthropogenic impacts. Because natural resource managers cannot differentiate these few successful males a priori, they cannot differentially protect them from potentially adverse human activities, such as opening the fishing season on a preset date that may fall before the end of brood-guarding in a given year. The evaluation of variables that might influence differences in male reproductive success included male length and age, spawning date, number of eggs and fry within a nest, nest depth, and dominant substrate type both within and surrounding the nest. Logistic regression analysis indicated that none of these variables were significant predictors of male reproductive success (P > 0.05). Additionally, linear regression analysis suggested the lack of a relationship between the number of fall YOY produced per male and these variables. However, a goodness-of-fit test to the Poisson distribution indicated that the number of YOY produced per male does not occur at random (P < 0.001), suggesting that reproductive success was influenced by factors not measured in this study.
We defined relationships between current velocity and displacement of young smallmouth bass Micropterus dolomieui from nests, and between velocity and the distribution, swimming, respiration, feeding, and growth of larger young. Young that had recently risen from the nest gravel (7–9 mm standard length, SL) were displaced from field nest sites and from laboratory flumes at low velocities (8 mm/s). Nests in areas of higher velocities (15 mm/s) failed to produce young. Comparison of respiration and foraging rates of young fish (16–71 mm SL) in laboratory flumes suggested that the ratio of feeding reward to energy expenditure reached a maximum at current velocities between 80 and 130 mm/s. This velocity range produced maximum growth in the flumes and was also the range most frequented by young (43–116 mm SL) in the Mississippi River.
Larval fish drift in the rocky-bottomed Susquehanna River (northeastern Pennsylvania) was investigated during 1974-1975. Near SSES (Susquehanna Steam Electric Station) at least 18 species of drifting larvae were collected by nets mounted on a stationary boat or by pumping. Maximum densities of 15.4 and 27.1 larvae/10 m3 were found in June 1974 and 1975, respectively. Quillback, Carpiodes cyprinus (56%), minnows (25%), and carp, Cyprinus carpio (14% of the total) were the most abundant larvae caught in 1974 by pumping. The few larvae that drifted during the day were mostly near the bottom. Large numbers of quillback, white sucker (Catostomus commersoni), shorthead redhorse (Moxostoma macrolepidotum), and tessellated darter (Etheostoma olmstedi) larvae drifted near the river surface at night. Drift was maximum at about 2400 h. Overall, the day/night drift ratio was 1/3.8.
The homing behavior of smallmouth bass was studied in two small Ozark streams; Big Buffalo Creek with relatively permanent pools, and Little Saline Creek with many unstable pools continually altered by the shift of chert gravel. The smallmouth bass in both streams normally restrict their movements to limited sections of the streams, usually one distinct pool.In Little Saline Creek, 39 of 97 tagged bass recaptured had deserted their home pools. Of these, 24 were forced to move because their home pools had been eliminated by deposition of chert gravel. It was concluded that the movement of smallmouth bass in Little Saline Creek was directly correlated with the physical stability of the stream.The bass of Big Buffalo Creek moved somewhat more frequently than the bass in the stable pools of Little Saline Creek although the pools of Big Buffalo Creek were comparatively stable during the study period. Fifteen bass made voluntary trips of 100 to 2,845 feet to other pools, and later returned to their home pools. Such voluntary straying and homing behavior has not been reported before for warmwater fish.
Tag recoveries of angler-caught smallmouth bass Micropterus dolomieu were monitored in a 1.9-mi special regulation area of the Zumbro River where anglers were required to release fish greater than 9 in and in two areas where mandatory release was not required. For all areas combined, an average of 16% of the fish that were caught at least one time and released were recaught by anglers during the 2 years the fishery was studied. Estimates of numbers of fish recaught were affected by high tag loss (46%) and unknown angler nonresponse rates. Previously released smallmouth bass contributed to angler catch in all areas, including an area downstream of the primary survey site; however, the majority of the fish that were recaught were released by anglers in the special regulation area. Catch rates in the special regulation area averaged 1.1 fish/h and were greater than in standard regulation areas; however, they were influenced by numbers of smallmouth bass and angler skill and effort. Most fish within the 1.9-mi reach were protected from harvest, and 60% of the fish tagged in the special regulation area were caught by anglers in the same area. Stream lengths of less than 2 mi may adequately function as special regulation areas for smallmouth bass where fishing pressure is concentrated during the summer; however, movement of fish into areas with legal harvest may reduce the numbers of fish that are recaught.
Movement of 248 marked and recaptured native smallmouth bass (Micropterus dolomieui), native rock bass (Ambloplites rupestris), and hatchery smallmouth bass released in a headwater tributary of the Little Miami River of Ohio during 1953 through 1957 is described. More than 91 percent of the native fishes of both species reported by anglers were taken within 1/2 mile of release points. Recaptures made with electric shocker and hoop nets indicated that appreciable numbers of native fish remained within limited areas of one to several pools between successive years. Considerable numbers of stocked smallmouth bass moved away from release points. A total of 35.7 percent of fish stocked in optimum habitat in 1953 and later recovered by anglers had moved distances greater than 1/2 mile. All fish stocked in submarginal habitat upstream in 1955 and later recovered by anglers moved more than 1/2 mile. Except for one recapture 6 miles upstream from the release point, all returns of stocked fish were from downstream at distances ranging up to 70 miles. The proportion of fish stocked in optimum habitat in 1953 and recaptured 11 to 50 miles downstream increased significantly from 1953 to 1954, suggesting a progressive downstream dispersal. Movement of hatchery smallmouth bass was independent of size at stocking in 1953. Rapid disappearance of the 1953-stocked fish may have resulted from higher mortality, as well as from movement.
Migration of smallmouth bass Micropterus dolomieui between summer and winter habitats was investigated from 1985 to 1987 in the Embarrass and Wolf rivers of Wisconsin. Smallmouth bass of age 2 and older (> 200 mm, total length) migrated from the Embarrass River downstream 69–87 km to the Wolf River when the water temperature fell below 16°C in autumn. Smallmouth bass returned to the Embarrass River in April and May, and most individuals returned to the same 5-km reach of river. Adults (age 4 and older, > 280 mm) migrated sooner than subadult fish.
Observations on smallmouth black bass, Micropterus dolomieu, of the Columbia River were possible because of a transplantation program undertaken by local sportsmen and because of studies made by the U. S. Public Health Service and the General Electric Company to evaluate effects of the radioactive effluent from the Hanford reactors. The average bass caught with sport-fishing gear was 15 1/2 inches long and weighed 40 ounces. Females were larger and made up a greater portion of the catch than males. Age was from three to eleven years but seven and eight-year-old fish made up about half of the catch. Growth was rapid in spite of a short season and water temperatures below that considered optimum.Some spawning occured in sloughs as early as April, but was unsuccessful because of a subsequent drop in temperature. Fry hatched from eggs spawned in July and August when temperatures were from 60 to 75°F. Transplanted bass move about considerably, but a definite migratory pattern was not established. Some fish moved over forty miles and many returned to the place of initial capture.Radioactive materials, which originated in the effluent from the reactors, were acquired by the bass through food chains. The principal isotope concentrated in the fish and other river animals was radiophosphorus. The level of radioactivity in the bass was greatest in September and least in April. No adverse effects on bass or food organisms, attributable to radioactive effluents, could be detected. The radioactive contamination of the bass was too low to constitute a hazard to persons who might eat them.
Movements and behavior of 56 stream-spawning smallmouth bass and rock bass from Lake Ontario were examined in spring and summer 1985 and 1986. Fish were captured by electrofishing near spawning areas in two tributaries 60 km apart, fitted with temperature-sensing radiotransmitters and released in their “home” tributaries or displaced to the lake 3–10 km from these tributaries. Twenty-six percent of displaced smallmouth bass and 42% of rock bass returned to their original sites of capture in tributaries. Non-homing fish generally dispersed along the lake shore and eventually established small residence areas in the lake, often near home or other tributaries. No differences were observed in movement rates, temperatures occupied or diel activity patterns between years or tributary stocks, but differences were found between species and between lake and tributary habitats for smallmouth bass. Smallmouth bass homing to, or released in, tributaries generally established home ranges downstream from spawning areas and often occupied tributaries all summer, but rock bass did not. Both species occupied temperatures between 20–22 C in lake and tributary habitats when available. Smallmouth bass were most active in May, least active in July and generally more active in the lake than in tributaries. Rock bass activity did not appear to vary by season or habitat. Both species were most active in Lake Ontario at mid-day; differences in tributaries were less pronounced.