Largemouth bass, Micropterus salmoides (Lacepe`de), smallmouth bass, Micropterus dolomieu Lacepe`de, and yellow perch, Perca flavescens (Mitchill), were collected from the Hudson River, New York, USA, to compare the precision of age estimates derived from scales and otoliths. Similar procedures were used to compare otolith and spine ages from brown bullhead, Ameiurus nebulosus (Lesueur). Overall percent agreement between readers ranged from 91% to 98% for otoliths compared with 38% to 67% for scales and spines. Disagreement rates associated with scales and spines increased as fish grew older. Average percent error between readers was about an order of magnitude higher for scales and spines than for otoliths. Ages estimated from scales and spines progressively decreased as age increased based on otolith examination. The use of scales and spines to age largemouth bass, smallmouth bass, yellow perch and brown bullheads from the northeastern US was less precise and will likely lead to underestimation of age of larger and older fish.

Larvae of black crappies Pomoxis nigromaculatus, white crappies P. annularis, and white bass Morone chrysops were sampled in 1992–1996 from Normandy Reservoir, Tennessee, with a 1 × 2‐m neuston net. Larval crappies were not captured in 1992 or 1993, but densities over the remaining three years varied over two orders of magnitude. Larval white bass were collected every year, but densities also varied over two orders of magnitude among years. Larval crappies recruited to the gear at 9 mm total length (TL), but few over 15 mm were collected. Larval white bass recruited to the gear at 7 mm TL and continued to be sampled by the neuston net at lengths up to 35 mm TL. Peak larval crappie density in the neuston net samples was an accurate predictor of geometric mean number of age‐1 crappies per hectare 1 year later in midsummer cove samples (r2 = 0.99, P = 0.0001). Peak white bass density in the neuston net samples was an accurate predictor of geometric mean catch of age‐0 white bass in fall gill‐net samples (r2 = 0.77, P = 0.05). Larval sampling of these species over a few weeks each spring in Normandy Reservoir can accurately demonstrate the presence or absence of strong year‐classes much earlier and with less effort than traditional sampling techniques such as fall gillnetting or cove sampling. Early detection of year‐class strength via neuston‐net sampling may allow managers to predict poor year‐classes early in the year and initiate remedial actions such as supplemental stocking or regulation changes in a more timely manner.

Sport fish from Normandy Reservoir, Tennessee, were sampled for more than 6 years with a variety of gears targeting different life stages. Normandy Reservoir experienced different hydrologic regimes over the sampling period that we roughly grouped into dry years (1992 and 1995), intermediate years (1993 and 1997), and wet years (1994 and 1996). Year‐class strength of largemouth bass Micropterus salmoides was fixed each year by late summer or early fall. Catch of age‐1 largemouth bass in spring electrofishing samples was directly related to the number of days the reservoir was at or over full pool when the fish were age 0. Largemouth bass produced in a wet year and intermediate year were more than twice as abundant at age 3 than fish produced in two dry years. Recruitment of spotted bass M. punctulatus could not be linked to reservoir hydrology. Crappies Pomoxis spp., white bass Morone chrysops, and saugeyes (walleye Stizostedion vitreum × sauger S. canadense) produced poor year‐classes in dry years and strong year‐classes in wet years. The responses of these latter three taxa in intermediate years were variable, although they were more characteristic of dry‐year responses than wet‐year responses. Recruitment of crappies, white bass, and saugeyes was positively related to mean daily discharge of the reservoir in the prespawn period (1 January to 31 March) each year. Recruitment of largemouth bass was dependent on high water during the spring and summer when fish were age 0. Water‐level fluctuation in this Tennessee reservoir played a pivotal role in regulating year‐class strength of most sport fish species. Attempts to enhance year‐class strength of fishes in tributary storage impoundments should focus on altering the hydrology of systems.

The Shoal Bass Micropterus cataractae is a fluvial specialist endemic to the Apalachicola River drainage in Alabama, Florida, and Georgia that has experienced declines throughout much of its range. The Flint River, Georgia, represents the largest remaining intact ecosystem for Shoal Bass in their native range. Spotted Bass M. punctulatus have recently been introduced into this system, causing concern about the potential negative impacts the species may have on the native populations of Shoal Bass and Largemouth Bass M. salmoides. To assess the symmetry and strength of competition and gain the greatest perspective on the interrelationships among these sympatric, congeneric species, we compared the movement patterns and habitat use of all three species of black bass present in this system. Fifteen Shoal Bass, 10 Largemouth Bass, and 6 Spotted Bass were implanted with radio transmitters in the Flint River and tracked for a period of 1 year (2008). Daily and hourly movements did not vary among species or season, though individuals of each species were observed moving >5 km to shoal complexes during spring. Habitat overlap varied between species during the study; overlap was highest between Spotted Bass and Largemouth Bass, intermediate between Spotted Bass and Shoal Bass, and lowest between Shoal Bass and Largemouth Bass. Shoal Bass tended to select coarse rocky habitat, while Largemouth Bass tended to select depositional habitat. Spotted Bass exhibited the widest niche breadth and generally used habitat in proportion to its availability. Use of similar habitats by these three species during the spring spawning period highlights the potential risk of genetic introgression of the two native species by introduced Spotted Bass. Physical barriers that restrict access to habitat during long‐distance seasonal movements, as observed for several Shoal Bass in this study, may negatively impact populations of this species. Received March 31, 2012; accepted October 12, 2012

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We evaluated the potential effect of minimum size restrictions on crappies Pomoxis spp. in 12 large Tennessee reservoirs. A Beverton–Holt equilibrium yield model was used to predict and compare the response of these fisheries to three minimum size restrictions: 178 mm (i.e., pragmatically, no size limit), 229 mm, and the current statewide limit of 254 mm. The responses of crappie fisheries to size limits differed among reservoirs and varied with rates of conditional natural mortality (CM). Based on model results, crappie fisheries fell into one of three response categories: (1) In some reservoirs (N = 5), 254‐mm and 229‐mm limits would benefit the fishery in terms of yield if CM were low (30%); the associated declines in the number of crappies harvested would be significant but modest when compared with those in other reservoirs. (2) In other reservoirs (N = 6), little difference in yield existed among size restrictions at low to intermediate rates of CM (30–40%). In these reservoirs, a 229‐mm limit was predicted to be a more beneficial regulation than the current 254‐mm limit. (3) In the remaining reservoir, Tellico, size limits negatively affected all three harvest statistics. Generally, yield was negatively affected by size limits in all populations at a CM of 50%. The number of crappies reaching 300 mm was increased by size limits in most model scenarios; however, associated declines in the total number of crappies harvested often outweighed the benefits to size structure when CM was 40% or higher. When crappie growth was fast (reaching 254 mm in less than 3 years) and CM was low (30%), size limits were most effective in balancing increases in yield and size structure against declines in the total number of crappies harvested. The variability in predicted size‐limit responses observed among Tennessee reservoirs suggests that using a categorical approach to applying size limits to crappie fisheries within a state or region would likely be a more effective management strategy than implementing a single, areawide regulation.

Black crappies Pomoxis nigromaculatus and white crappies P. annularis were sampled to index recruitment in seven Tennessee reservoirs (four main‐stem and three tributary storage impoundments). Crappie recruitment in tributary storage impoundments appeared to be consistently higher in years of high discharge during the prespawn period (1 January–31 March). A similar relation was found in one main‐stem impoundment; however, crappie recruitment in two main‐stem impoundments was inversely related to discharge during the spawning period (1 April–30 May), and little recruitment variation was found in the fourth main‐stem impoundment. In general, reservoir hydrology appeared to have a stronger effect on crappie recruitment in tributary storage impoundments than in main‐stem impoundments, possibly because recruitment was more variable in tributary systems. Thus, it is likely that crappie populations will rarely have strong year‐classes simultaneously over a wide geographic area or even within a single watershed.

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