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Predation can affect both phenotypic variation and population productivity in the wild, but quantifying evolutionary and demographic effects of predation in natural environments is challenging. The aim of this study was to estimate selection differentials and coefficients associated with brown bear (Ursus arctos) predation in wild sockeye salmon (Oncorhynchus nerka) populations spawning in pristine habitat that is often subject to intense predation pressure. Using reconstructed genetic pedigrees, individual reproductive success (RS) was estimated in two sockeye salmon populations for two consecutive brood years with very different predation intensities across brood years. Phenotypic data on individual adult body length, body depth, stream entry timing and reproductive lifespan were used to calculate selection coefficients based on RS, and genetic variance components were estimated using animal models. Bears consistently killed larger and more recently arrived adults, although selection differentials were small. In both populations, mean RS was higher in the brood year experiencing lower predation intensity. Selection coefficients were similar across brood years with different levels of predation, often indicating stabilizing selection on reproductive lifespan as well as directional selection for longer reproductive lifespan. Despite these selection pressures, genetic covariation of morphology, phenology and lifespan appears to have maintained variation in spawner body size and stream entry timing in both populations. Our results therefore suggest considerable demographic but limited evolutionary effects of bear predation in the two study populations.

We investigated the evolutionary relationships among five sympatric morphs of Dolly Varden Salvelinus malma(white, Schmidti, longhead, river, and dwarf) inhabiting landlocked Kronotsky Lake on the Kamchatka Peninsula, Russia, and an anadromous population below the barrier waterfall on the outflowing Kronotsky River. Morphological analyses indicated phenotypic differentiation corresponding to preferred habitat, the longhead (a limnetic piscivorous morph) having a fusiform body, long jaw, and short fins and the Schmidti (a benthic morph) having a robust body, small jaw, and long fins. Analysis of molecular variance among the Kronotsky Lake morphs indicated that contemporary gene flow is restricted both among morphs within locations and among locations within morphs. Gene flow from Kronotsky Lake into the anadromous population also appears to be restricted. Our findings indicate that there are two divergent evolutionary lineages, one consisting of the white, Schmidti, river, and dwarf morphs and the other of the longhead morph and the anadromous population, which suggests that Kronotsky Lake was subject to separate waves of immigration. The Kronotsky Lake Dolly Varden morphs may represent an example of ecological speciation in progress, and we present a working hypothesis for the diversification of morphs within Kronotsky Lake.

Hatcheries produce Pacific salmon and trout Oncorhynchusspp. for many purposes, including fishery enhancement. The genetic integrity of wild populations spawning near such hatcheries may depend on the efficacy of their spatial or temporal separation from hatchery fish. We describe a simple, novel approach based on the examination of scales from an iteroparous species, steelhead O. mykiss, to evaluate whether the ratio of hatchery-produced adults to wild adults on the spawning grounds met recommended levels. In this river, migrating steelhead are diverted into the hatchery by a weir. Hatchery-produced fish are manually spawned and killed in the hatchery, whereas wild fish are passed over the weir and allowed to spawn naturally upstream from the hatchery. Therefore, in principle, all hatchery-produced adults should be captured at the hatchery on their first spawning migration. However, scales from 8.3% (58 of 699) of female and 2.6% (22 of 844) of male hatchery-produced steelhead adults showed evidence of previous spawning migrations. Although this frequency was lower than the incidence of repeat spawning by wild fish (males, 11.0%; females, 20.3%), these records nevertheless indicated significant reproductive opportunities in the wild for hatchery-produced fish. Combining these frequencies of repeat spawning with estimates of the survival and numbers of wild fish, we modeled the ratio of hatchery to wild fish on the spawning grounds using data from eight return years. This ratio exceeded the recommended levels under all reasonable scenarios modeled (14.7-89.6% hatchery fish). Combined with evidence of spatial and temporal overlap, our data suggest that unless changes are made to increase the capture efficiency of adults at Washington State's Forks Creek Hatchery and similar hatcheries relying on segregated stocks, the risks of genetic introgression and ecological interactions with wild steelhead populations will remain high.

AbstractHatcheries produce Pacific salmon and trout Oncorhynchusspp. for many purposes, including fishery enhancement. The genetic integrity of wild populations spawning near such hatcheries may depend on the efficacy of their spatial or temporal separation from hatchery fish. We describe a simple, novel approach based on the examination of scales from an iteroparous species, steelhead O. mykiss, to evaluate whether the ratio of hatchery-produced adults to wild adults on the spawning grounds met recommended levels. In this river, migrating steelhead are diverted into the hatchery by a weir. Hatchery-produced fish are manually spawned and killed in the hatchery, whereas wild fish are passed over the weir and allowed to spawn naturally upstream from the hatchery. Therefore, in principle, all hatchery-produced adults should be captured at the hatchery on their first spawning migration. However, scales from 8.3% (58 of 699) of female and 2.6% (22 of 844) of male hatchery-produced steelhead adults showed evidence of previous spawning migrations. Although this frequency was lower than the incidence of repeat spawning by wild fish (males, 11.0%; females, 20.3%), these records nevertheless indicated significant reproductive opportunities in the wild for hatchery-produced fish. Combining these frequencies of repeat spawning with estimates of the survival and numbers of wild fish, we modeled the ratio of hatchery to wild fish on the spawning grounds using data from eight return years. This ratio exceeded the recommended levels under all reasonable scenarios modeled (14.7-89.6% hatchery fish). Combined with evidence of spatial and temporal overlap, our data suggest that unless changes are made to increase the capture efficiency of adults at Washington State's Forks Creek Hatchery and similar hatcheries relying on segregated stocks, the risks of genetic introgression and ecological interactions with wild steelhead populations will remain high.

AbstractWe investigated the evolutionary relationships among five sympatric morphs of Dolly Varden Salvelinus malma(white, Schmidti, longhead, river, and dwarf) inhabiting landlocked Kronotsky Lake on the Kamchatka Peninsula, Russia, and an anadromous population below the barrier waterfall on the outflowing Kronotsky River. Morphological analyses indicated phenotypic differentiation corresponding to preferred habitat, the longhead (a limnetic piscivorous morph) having a fusiform body, long jaw, and short fins and the Schmidti (a benthic morph) having a robust body, small jaw, and long fins. Analysis of molecular variance among the Kronotsky Lake morphs indicated that contemporary gene flow is restricted both among morphs within locations and among locations within morphs. Gene flow from Kronotsky Lake into the anadromous population also appears to be restricted. Our findings indicate that there are two divergent evolutionary lineages, one consisting of the white, Schmidti, river, and dwarf morphs and the other of the longhead morph and the anadromous population, which suggests that Kronotsky Lake was subject to separate waves of immigration. The Kronotsky Lake Dolly Varden morphs may represent an example of ecological speciation in progress, and we present a working hypothesis for the diversification of morphs within Kronotsky Lake.

Here we present a comprehensive method for proteome analysis that integrates both intact protein measurement (“top-down”) and proteolytic fragment characterization (“bottom-up”) mass spectrometric approaches, capitalizing on the unique capabilities of each method. This integrated approach was applied in a preliminary proteomic analysis of Shewanella oneidensis, a metal-reducing microbe of potential importance to the field of bioremediation. Cellular lysates were examined directly by the “bottom-up” approach as well as fractionated via anion-exchange liquid chromatography for integrated studies. A portion of each fraction was proteolytically digested, with the resulting peptides characterized by on-line liquid chromatography/tandem mass spectrometry. The remaining portion of each fraction containing the intact proteins was examined by high-resolution Fourier transform mass spectrometry. This “top-down” technique provided direct measurement of the molecular masses for the intact proteins and thereby enabled confirmation of post-translational modifications, signal peptides, and gene start sites of proteins detected in the “bottom-up” experiments. A total of 868 proteins from virtually every functional class, including hypotheticals, were identified from this organism. Keywords: microbial proteomics • mass spectrometry • intact proteins • LC−MS/MS • database searching

The freshwater prosobranch snail Potamopyrgus antipodarumis an important model system for studying the maintenance of sexual reproduction in its native New Zealand. Since introduction to the UK in the 1850s, the species has spread throughout Europe and recently the USA. We present the first microsatellites for P. antipodarum. Using two isolation protocols, which are qualitatively compared, we have developed PCR primers for three di- and four trinucleotide microsatellites. All loci proved to be polymorphic, when screened for variability in several UK populations. These markers should be of considerable utility in future population and ecological genetics studies of this species.

Over the last decades, numerical methods have gained increasing importance in practical geotechnical engineering and numerical methods have become a standard tool in geotechnical design, widely accepted by the geotechnical profession. The advantages of numerical analyses for solving practical problems have been recognised, and developments in software and hardware allow their application in practice with reasonable effort. However, there is still a gap between practice and research and, often unnecessary, simplifications are made in practice and therefore the full power of numerical analyses is not always utilised. One reason for this discrepancy is a lack of transfer of knowledge from research into practice but also a lack of theoretical background of numerical methods, constitutive modelling and modern soil mechanics in practice. In this paper, the application of advanced numerical models for solving practical geotechnical problems is shown, whereas the examples have been chosen in such a way that different aspects are highlighted in each case. Results from fibre-optic measurements for a pull-out test of a ground anchor in soft soil could be reproduced by employing advanced constitutive models, in particular for the grout, in the bonded length of the anchor. For this test, a class-A prediction has been made and numerical results have then been compared with in situ measurements. The back-analysis of a slow-moving landslide is presented next, where the rate of deformation is influenced by water level changes in a reservoir for a pumping power plant, creep of lacustrine sediments and environmental effects such as rainfall infiltration. Finally, some results of modelling cone penetration testing in silts are presented highlighting the effects of anisotropic permeability.