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Dams have many effects on river systems, including impeding the migratory movements of fishes. However, locks associated with lock-and-dam structures may be useful for passing fish during their migrations. We investigated the potential to facilitate fish passage at dams through two navigational lock structures on the Alabama River, Alabama—Millers Ferry Lock and Dam (L&D) and Claiborne L&D—using targeted, nonnavigational lock operations. The movements of PaddlefishPolyodon spathulawith implanted ultrasonic tags and/or radio tags were tracked via both manual receivers and submersible ultrasonic receivers (SURs) deployed inside of the lock chambers and above and below each dam to quantify migration characteristics and determine whether fish passage occurred. We tagged a total of 96 fish (79 received sonic tags, 4 received radio tags, and 13 received both types of tag), and we recorded over 275,000 SUR detections of 84 individuals and 91 manual detections of 39 individuals. Although nonnavigational lock operations increased the number of days available for potential passage by 0.5–4.7 times, only seven Paddlefish passed upstream through the locks (8% passage rate). Most of the fish movement past dams occurred during spring, when many riverine fish make spawning migrations. Movement past Claiborne Dam occurred most often over the spillway (87% of passage) during high-water events. Our results suggest that while specialized nonnavigational lock operations along the Alabama River increased opportunities for upstream fish passage, relatively few Paddlefish actually moved upstream through the lock chambers. Received June 4, 2014; accepted December 2, 2014 [ABSTRACT FROM PUBLISHER]

Many water bodies throughout North America have experienced shoreline development such as armoring with bulkheads or riprap to reduce erosion and protect property. Although research has addressed the influence of such development in systems containing vegetation, systems that experience water-level fluctuations, and thus have limited vegetation, have received little attention. Here we quantify the effects of 4 types of shoreline development (bulkhead, riprap, bulkhead with riprap, and undeveloped) on the aquatic community in Lake Martin, Alabama, a reservoir that experiences large annual water-level fluctuations. We quantified abundance and species composition of larval, juvenile, and adult fishes; abundance and species composition of aquatic macroinvertebrates and zooplankton; and water quality characteristics at each site. Abiotic factors and lower trophic levels (i.e., chlorophylla, zooplankton, macroinvertebrates) did not differ across shoreline types. In contrast, fish abundance was highest at sites with riprap, and fish species richness and species diversity both tended to be highest at undeveloped sites. While bluegill (Lepomis machrochirus) was the most abundant fish species at all shoreline types, the other commonly collected species showed strong association with particular habitats. Centrarchids, including bluegill, were most abundant at developed sites, and cyprinids were most abundant at undeveloped sites. Based on our findings, an interspersion of different shoreline types may be sufficient for maintaining fish community diversity; if shorelines cannot be interspersed, then some undeveloped shorelines should be maintained in reservoirs with continuing human development, and when shorelines are armored, riprap should be included to provide interstitial spaces and shallow water for fish habitat. [Supplementary materials are available for this article. Go to the publisher's online edition ofLake and Reservoir Managementfor the following free supplemental resource(s): Supplemental Tables 1–3] [ABSTRACT FROM AUTHOR]

We examined the effects of latitude of origin on the first-year growth and survival of largemouth bass Micropterus salmoides. We brought largemouth bass from three latitudinally disparate populations (northern largemouth bass M. s. salmoides from south-central Wisconsin; Florida largemouth bass M. s. floridanus, originally from central Florida but currently stocked throughout Alabama; and native northern largemouth bass from southern Alabama) to a common rearing environment to compare their age-0 growth over two replicate growing seasons. During 1999, the northern subspecies from Wisconsin grew faster than the northern or Florida subspecies from Alabama. However, in 2000 the Florida subspecies grew faster than the age-O fish from either northern subspecies population. Our results indicate that the effects of prey availability and age-O density can overwhelm any predisposition for growth based on latitudinal or genetic origin. Given concerns about the genetic consequences of largemouth bass stockings, the lack of any consistent growth advantage in the first year represents an important piece of information to be taken into account when deciding about stocking nonnative subspecies of largemouth bass. [ABSTRACT FROM AUTHOR]

Temperature and seasonal effects on foraging activity of Solenopsis invicta Buren (red imported fire ant) in Oklahoma were investigated by periodically quantifying the number of ants captured in baited vials for 2 yr. All temperature parameters (soil surface, 2 cm, 15 cm, mound surface, mound 5 cm deep, and mound 10 cm deep) except ambient at 1 m above soil surface were significant predictors of foraging activity; soil temperature at 15 cm was the best individual predictor, explaining 34% of variability in foraging activity. A combined quadratic model including mound surface temperature and season (weeks) explained 63% of the variability in foraging activity. Comparison with a similar study conducted in Florida revealed differences in the percentage of the year favorable for maximal foraging (≈25% in Oklahoma versus 42-59% in Florida). These data suggest that recommendations for timing of insecticidal bait applications against S. invicta that are appropriate in more southern portions of the fire ant range may not be appropriate for Oklahoma. [ABSTRACT FROM AUTHOR]