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U.S. Geological Survey - Great Lakes Science Center


  • Ke Li, Tyler J. Buchinger, Ugo Bussy, Skye D. Fissette, Nicholas S. Johnson, and Weiming Li 2015 Quantification of 15 bile acids in lake charr feces by ultra-high performance liquid chromatography-tandem mass spectrometry. Elsevier . Journal of Chromatography B

    Many fishes are hypothesized to use bile acids (BAs) as chemical cues, yet quantification of BAs in biological samples and the required methods remain limited. Here, we present an UHPLC-MS/MS method for simultaneous, sensitive, and rapid quantification of 15 BAs, including free, taurine, and glycine conjugated BAs, and application of the method to fecal samples from lake charr (Salvelinus namaycush). The analytes were separated on a C18 column with acetonitrile–water (containing 7.5 mM ammonium acetate and 0.1% formic acid) as mobile phase at a flow rate of 0.25 mL/min for 12 min. BAs were monitored with a negative electrospray triple quadrupole mass spectrometer (Xevo TQ-STM). Calibration curves of 15 BAs were linear over the concentration range of 1.00–5,000 ng/mL. Validation revealed that the method was specific, accurate, and precise. The method was applied to quantitative analysis of feces extract of fry lake charr and the food they were eating. The concentrations of analytes CA, TCDCA, TCA, and CDCA were 242.3, 81.2, 60.7, and 36.2 ng/mg, respectively. However, other taurine conjugated BAs, TUDCA, TDCA, and THDCA, were not detected in feces of lake charr. Interestingly, TCA and TCDCA were detected at high concentrations in food pellets, at 71.9 and 38.2 ng/mg, respectively. Application of the method to feces samples from lake charr supported a role of BAs as chemical cues, and will enhance further investigation of BAs as chemical cues in other fish species.

    Contribution #1948
  • Paul C. Kusnierz, Christopher M. Holbrook, David L. Feldman 2015 An evaluation of a bed instability index as an indicator of habitat quality in mountain streams of the northwestern United States. Springer . Environmental Monitoring and Assessment 187 (8).

    Managers of aquatic resources benefit from indices of habitat quality that are reproducible and easy to measure, demonstrate a link between habitat quality and biota health, and differ between human-impacted (i.e., managed) and reference (i.e., nonimpacted or minimally impacted) conditions. The instability index (ISI) is an easily measured index that describes the instability of a streambed by relating the tractive force of a stream at bankfull discharge to the median substrate size. Previous studies have linked ISI to biological condition but have been limited to comparisons of sites within a single stream or among a small number of streams. We tested ISI as an indicator of human impact to habitat and biota in mountain streams of the northwestern USA. Among 1428 sites in six northwestern states, ISI was correlated with other habitat measures (e.g., residual pool depth, percent fine sediment) and indices of biotic health (e.g., number of intolerant macroinvertebrate taxa, fine sediment biotic index) and differed between managed and reference sites across a range of stream types and ecoregions. While ISI could be useful in mountain streams throughout the world, this index may be of particular interest to aquatic resource managers in the northwestern USA where a large dataset, from which ISI can be calculated, exists.

    Contribution #1946
  • Roger S. Fujioka, Helena M. Solo-Gabriele, Muruleedhara N. Byappanahalli, and Marek Kirs 2015 U.S. Recreational Water Quality Criteria: A Vision for the Future. Multidisciplinary Digital Publishing Institute . International Journal of Environmental Research and Public Health 12 (7). pp. 7752-7776.

    This manuscript evaluates the U.S. Recreational Water Quality Criteria (RWQC) of 2012, based upon discussions during a conference held 11–13 March 2013, in Honolulu, Hawaii. The RWQC of 2012 did not meet expectations among the research community because key recommended studies were not completed, new data to assess risks to bathers exposed to non-point sources of fecal indicator bacteria (FIB) were not developed, and the 2012 RWQC did not show marked improvements in strategies for assessing health risks for bathers using all types of recreational waters. The development of the 2012 RWQC was limited in scope because the epidemiologic studies at beach sites were restricted to beaches with point sources of pollution and water samples were monitored for only enterococci. The vision for the future is development of effective RWQC guidelines based on epidemiologic and quantitative microbial risk assessment (QMRA) studies for sewage specific markers, as well as human enteric pathogens so that health risks for bathers at all recreational waters can be determined. The 2012 RWQC introduced a program for states and tribes to develop site-specific water quality criteria, and in theory this approach can be used to address the limitations associated with the measurements of the traditional FIB.

    Contribution #1944
  • Martin A. Stapanian, Christopher A. Myrick 2015 Ecology, culture, and management of Burbot: an introduction. Springer . Hydrobiologia
    Contribution #1942
  • David N. Zaya, Stacey A. Leicht-Young, Noel B. Pavlovic, Kevin A. Feldheim, and Mary V. Ashley 2015 Genetic characterization of hybridization between native and invasive bittersweet vines (Celastrus spp.). Springer . Biological Invasions

    Hybridization associated with species introductions can accelerate the decline of native species. The main objective of this study was to determine if the decline of a North American liana (American bittersweet, Celastrus scandens) in the eastern portion of its range is related to hybridization with an introduced congener (oriental bittersweet, C. orbiculatus). We used newly characterized microsatellite loci, a maternally-inherited chloroplast DNA marker, and field observation to survey individuals across the USA to determine the prevalence of hybrids, their importance in the invasion of C. orbiculatus, and the predominant direction of hybridization. We found that only 8.4 % of non-native genotypes were hybrids (20 of 239), and these hybrids were geographically widespread. Hybrids showed reduced seed set (decline of >98 %) and small, likely inviable pollen. Genetic analysis of a maternally inherited chloroplast marker showed that all 20 identified hybrids came from C. scandens seed parents. The strong asymmetry in pollen flow that favors fecundity in introduced males has the potential to greatly accelerate the decline of native species by wasting limited female reproductive effort.

    Contribution #1939
  • Richard T. Kraus, David H. Secor, Rebecca L. Wingate 2015 Testing the thermal-niche oxygen-squeeze hypothesis for estuarine striped bass. Springer . Environmental Biology of Fishes

    In many stratified coastal ecosystems, conceptual and bioenergetics models predict seasonal reduction in quality and quantity of fish habitat due to high temperatures and hypoxia. We tested these predictions using acoustic telemetry of 2 to 4 kg striped bass (Morone saxatilis Walbaum) and high-resolution spatial water quality sampling in the Patuxent River, a sub-estuary of the Chesapeake Bay, during 2008 and 2009. Striped bass avoided hypoxic (dissolved oxygen ≤2 mg·l−1) subpycnocline waters, but frequently occupied habitats with high temperatures (>25 °C) in the summer months, as cooler habitats were typically not available. Using traditional concepts of the seasonal thermal-niche oxygen-squeeze, most of the Patuxent estuary would be considered unsuitable habitat for adult striped bass during summer. Application of a bioenergetics model revealed that habitats selected by striped bass during summer would support positive growth rates assuming fish could feed at one-half of maximum consumption. Occupancy of the estuary during summer by striped bass in this study was likely facilitated by sufficient prey and innate tolerance of high temperatures by sub-adult fish of the size range that we tagged. Our results help extend the thermal-niche oxygen-squeeze hypothesis to native populations of striped bass in semi-enclosed coastal systems. Tolerance of for supraoptimal temperatures in our study supports recent suggestions by others that the thermal-niche concept for striped bass should be revised to include warmer temperatures.

    Contribution #1936
  • Daniel S. Stich, Michael M. Bailey, Christopher M. Holbrook, Michael T. Kinnison, and Joseph D. Zydlewski 2015 Catchment-wide Survival of Wild-and Hatchery-Reared Atlantic Salmon Smolts in a Changing System. NRC Research Press . Canadian Journal of Fisheries and Aquatic Sciences

    We developed a hierarchical multi-state model to estimate survival of Atlantic salmon smolts in the Penobscot River, USA over a decade during which two main-stem dams were removed from the catchment. We investigated effects of 1) environmental factors, 2) rearing history, and 3) management actions including dam removal, turbine shutdown, and installation of new powerhouses. Mean ± S.D. smolt survival per kilometer was higher through free-flowing reaches of the catchment (0.995 ± 0.004•km-1) than through reaches containing dams that remain in the system (0.970 ± 0.019•km-1). We observed maximum survival between 12 °C and 17 °C and at intermediate discharges (1 200 m3•s-1). Smolt survival increased concurrent with dam removal, and decreased following increases in hydropower generation. The greatest increase in smolt survival followed seasonal turbine shutdowns at a dam located on the largest tributary to the Penobscot River, while other shutdowns had little influence. Our model provides a useful tool for assessing changes to survival of migratory species and will be useful for informing stocking plans to maximize numbers of smolts leaving coastal systems.

    Contribution #1934
  • James H. Johnson, Russell D. McCullough, James F. Farquhar, and Irene Mazzocchi 2015 Little Galloo Island, Lake Ontario: Two decades of studies on the diet, fish consumption, and management of double-crested cormorants. Elsevier . Journal of Great Lakes Research 41 (2). pp. 652-658.

    The double-crested cormorant (Phalacrocorax auritus) colony at Little Galloo Island, Lake Ontario has been a Great Lakes focal point of controversy regarding cormorant–fish interactions for over two decades. We examined cormorant diet and fish consumption at the colony from 1992 to 2013. During this time period, two events, management actions and round goby (Neogobius melanostomus) invasion, occurred that affected the number of fish consumed by cormorants and their diet composition. The purpose of this study was to evaluate the effects of round goby on the feeding ecology of cormorants and evaluate the efficacy of management actions on meeting cormorant population targets at the colony. Round goby first appeared in the diet in 2004 (0.8%) and within one year were the primary prey (29.3%). The presence of round goby in the diet of cormorants: (1) eliminated seasonal variability in diet composition, (2) reversed seasonal trends in the number of fish consumed daily, (3) increased daily fish consumption, and (4) significantly reduced the consumption of other species including yellow perch and smallmouth bass. Management actions, such as egg oiling and culling, were also effective in reducing nesting activity and the number of cormorant feeding days at the Little Galloo Island colony. There is evidence that the combination of management actions and round goby may have allowed some population recovery of yellow perch and smallmouth bass in eastern Lake Ontario.

    Contribution #1933
  • Martin A. Stapanian, Mick Micacchion, and Jean V. Adams 2015 Wetland habitat disturbance best predicts metrics of an amphibian index of biotic integrity. Elsevier . Ecological Indicators 56 pp. 237-242.

    Regression and classification trees were used to identify the best predictors of the five component metrics of the Ohio Amphibian Index of Biotic Integrity (AmphIBI) in 54 wetlands in Ohio, USA. Of the 17 wetland- and surrounding landscape-scale variables considered, the best predictor for all AmphIBI metrics was habitat alteration and development within the wetland. The results were qualitatively similar to the best predictors for a wetland vegetation index of biotic integrity, suggesting that similar management practices (e.g., reducing or eliminating nutrient enrichment from agriculture, mowing, grazing, logging, and removing down woody debris) within the boundaries of the wetland can be applied to effectively increase the quality of wetland vegetation and amphibian communities.

    Contribution #1931
  • Talia Young, Olaf P. Jensen, Brian C. Weidel, Sudeep Chandra 2015 Natural trophic variability in a large, oligotrophic, near-pristine lake. Elsevier . Journal of Great Lakes Research 41 (2). pp. 463-472.

    Conclusions drawn from stable isotope data can be limited by an incomplete understanding of natural isotopic variability over time and space. We quantified spatial and temporal variability in fish carbon and nitrogen stable isotopes in Lake Hövsgöl, Mongolia, a large, remote, oligotrophic lake with an unusually species-poor fish community. The fish community demonstrated a high degree of trophic level overlap. Variability in d13C was inversely related to littoral-benthic dependence, with pelagic species demonstrating more d13C variability than littoral-benthic species. A mixed effects model suggested that space (sampling location) had a greater impact than time (collection year) on both d13C and d15N variability. The observed variability in Lake Hövsgöl was generally greater than isotopic variability documented in other large, oligotrophic lakes, similar to isotopic shifts attributed to introduced species, and less than isotopic shifts attributed to anthropogenic chemical changes such as eutrophication. This work complements studies on isotopic variability and changes in other lakes around the world.

    Contribution #1930


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