Photoperiod control of downstream movements of Atlantic salmon Salmo salar smolts
Gayle B. Zydlewski, Daniel S. Stich, Stephen D. McCormick
2014, Journal of Fish Biology (85) 1023-1041
This study provides the first direct observations that photoperiod controls the initiation of downstream movement in Atlantic salmon Salmo salar smolts. Under simulated natural day length (LDN) conditions and seasonal increases in temperature, smolts increased their downstream movements five-fold for a period of 1 month in late spring. Under the same conditions,...
Subsurface geometry of the San Andreas-Calaveras fault junction: Influence of serpentinite and the Coast Range Ophiolite
Janet Tilden Watt, David A. Ponce, Russell W. Graymer, Robert C. Jachens, Robert W. Simpson
2014, Tectonics (33) 2025-2044
While an enormous amount of research has been focused on trying to understand the geologic history and neotectonics of the San Andreas-Calaveras fault (SAF-CF) junction, fundamental questions concerning fault geometry and mechanisms for slip transfer through the junction remain. We use potential-field, geologic, geodetic, and seismicity data to investigate the...
Climatic and density influences on recruitment in an irruptive population of Roosevelt elk
Heath D. Starns, Mark A. Ricca, Adam Duarte, Floyd W. Weckerly
2014, Journal of Mammalogy (95) 925-932
Current paradigms of ungulate population ecology recognize that density-dependent and independent mechanisms are not always mutually exclusive. Long-term data sets are necessary to assess the relative strength of each mechanism, especially when populations display irruptive dynamics. Using an 18-year time series of population abundances of Roosevelt elk (Cervus elaphus roosevelti) inhabiting...
Spatial structuring within a reservoir fish population: implications for management
David R. Stewart, James M. Long, Daniel E. Shoup
2014, Marine and Freshwater Research (66) 202-212
Spatial structuring in reservoir fish populations can exist because of environmental gradients, species-specific behaviour, or even localised fishing effort. The present study investigated whether white crappie exhibited evidence of improved population structure where the northern more productive half of a lake is closed to fishing to provide waterfowl hunting opportunities....
Population-level effects of egg predation on a native planktivore in a large freshwater lake
David B. Bunnell, Justin G. Mychek-Londer, Charles P. Madenjian
2014, Ecology of Freshwater Fish (23) 604-614
Using a 37-year recruitment time series, we uncovered a field pattern revealing a strong, inverse relationship between bloater Coregonus hoyi recruitment success and slimy sculpin Cottus cognatus biomass in Lake Michigan (United States), one of the largest freshwater lakes of the world. Given that slimy sculpins (and deepwater sculpin Myoxocephalus...
Mississippi River nitrate loads from high frequency sensor measurements and regression-based load estimation
Brian A. Pellerin, Brian A. Bergamaschi, Robert J. Gilliom, Charles G. Crawford, John Franco Saraceno, C. Paul Frederick, Bryan D. Downing, Jennifer C. Murphy
2014, Environmental Science & Technology (48) 12612-12619
Accurately quantifying nitrate (NO3–) loading from the Mississippi River is important for predicting summer hypoxia in the Gulf of Mexico and targeting nutrient reduction within the basin. Loads have historically been modeled with regression-based techniques, but recent advances with high frequency NO3– sensors allowed us to evaluate model performance relative to...
Breeding site selection by coho salmon (Oncorhynchus kisutch) in relation to large wood additions and factors that influence reproductive success
Steven M. Clark, Jason B. Dunham, Jeffery R. McEnroe, Scott W. Lightcap
2014, Canadian Journal of Fisheries and Aquatic Sciences (71) 1498-1507
The fitness of female Pacific salmon (Oncorhynchus spp.) with respect to breeding behavior can be partitioned into at least four fitness components: survival to reproduction, competition for breeding sites, success of egg incubation, and suitability of the local environment near breeding sites for early rearing of juveniles. We evaluated the relative...
Transdisciplinary application of the cross-scale resilience model
Shana M. Sundstrom, David G. Angeler, Ahjond S. Garmestani, Jorge H. Garcia, Craig R. Allen
2014, Sustainability (6) 6925-6948
The cross-scale resilience model was developed in ecology to explain the emergence of resilience from the distribution of ecological functions within and across scales, and as a tool to assess resilience. We propose that the model and the underlying discontinuity hypothesis are relevant to other complex adaptive systems, and can...
Assessing the risk persistent drought using climate model simulations and paleoclimate data
Toby R. Ault, Julia E. Cole, Jonathan T. Overpeck, Gregory T. Pederson, David M. Meko
2014, Journal of Climate (27) 7529-7549
Projected changes in global rainfall patterns will likely alter water supplies and ecosystems in semiarid regions during the coming century. Instrumental and paleoclimate data indicate that natural hydroclimate fluctuations tend to be more energetic at low (multidecadal to multicentury) than at high (interannual) frequencies. State-of-the-art global climate models do not...
Evaluating the effects of land use on headwater wetland amphibian assemblages in coastal Alabama
Diane M. Alix, Christopher J. Anderson, J. Barry Grand, Craig Guyer
2014, Wetlands (34) 917-926
Anthropogenic land use is known to impact aquatic ecosystems in several ways, including increased frequency and intensity of floods, stream channel incision, sedimentation, and loss of microtopography. Amphibians are susceptible to changes in wetland and surrounding habitats. This study evaluated amphibian assemblages of fifteen headwater slope wetlands in coastal Alabama...
Probabilistic estimation of dune retreat on the Gold Coast, Australia
Margaret L. Palmsten, Kristen D. Splinter, Nathaniel G. Plant, Hilary F. Stockdon
2014, Shore & Beach (82) 35-43
Sand dunes are an important natural buffer between storm impacts and development backing the beach on the Gold Coast of Queensland, Australia. The ability to forecast dune erosion at a prediction horizon of days to a week would allow efficient and timely response to dune erosion in this highly populated...
Laboratory generated M -6 earthquakes
Gregory C. McLaskey, Brian D. Kilgore, David A. Lockner, Nicholas M. Beeler
2014, Pure and Applied Geophysics (171) 2601-2615
We consider whether mm-scale earthquake-like seismic events generated in laboratory experiments are consistent with our understanding of the physics of larger earthquakes. This work focuses on a population of 48 very small shocks that are foreshocks and aftershocks of stick–slip events occurring on a 2.0 m by 0.4 m simulated strike-slip...
A computer program for uncertainty analysis integrating regression and Bayesian methods
Dan Lu, Ming Ye, Mary C. Hill, Eileen P. Poeter, Gary Curtis
2014, Environmental Modelling and Software (60) 45-56
This work develops a new functionality in UCODE_2014 to evaluate Bayesian credible intervals using the Markov Chain Monte Carlo (MCMC) method. The MCMC capability in UCODE_2014 is based on the FORTRAN version of the differential evolution adaptive Metropolis (DREAM) algorithm of Vrugt et al. (2009), which estimates the posterior probability density...
Prolonged instability prior to a regime shift
Trisha Spanbauer, Craig R. Allen, David G. Angeler, Tarsha Eason, Sherilyn C. Fritz, Ahjond S. Garmestani, Kirsty L. Nash, Jeffery R. Stone
2014, PLoS ONE (9) 1-7
Regime shifts are generally defined as the point of ‘abrupt’ change in the state of a system. However, a seemingly abrupt transition can be the product of a system reorganization that has been ongoing much longer than is evident in statistical analysis of a single component of the system. Using...
Smolting in coastal cutthroat trout Onchorhynchus clarkii clarkii
Joseph D. Zydlewski, G. Zydlewski, B. Kennedy, W. Gale
2014, Journal of Fish Biology (85) 1111-1130
Gill Na+, K+-ATPase activity, condition factor and seawater (SW) challenges were used to assess the development of smolt characteristics in a cohort of hatchery coastal cutthroat trout Oncorhynchus clarkii clarkii from the Cowlitz River in Washington State, U.S.A. Gill Na+, K+-ATPase activity increased slightly in the spring, coinciding with an...
Survival of Atlantic salmon Salmo salar smolts through a hydropower complex
D.S. Stich, M.M. Bailey, Joseph D. Zydlewski
2014, Journal of Fish Biology (85) 1074-1096
This study evaluated Atlantic salmon Salmo salar smolt survival through the lower Penobscot River, Maine, U.S.A., and characterized relative differences in proportional use and survival through the main-stem of the river and an alternative migration route, the Stillwater Branch. The work was conducted prior to removal of two main-stem dams...
Straddling the tholeiitic/calc-alkaline transition: The effects of modest amounts of water on magmatic differentiation at Newberry Volcano, Oregon
Ben E. Mandler, Julie M. Donnelly-Nolan, Timothy L. Grove
2014, Contributions to Mineralogy and Petrology (168)
Melting experiments have been performed at 1 bar (anhydrous) and 1- and 2-kbar H2O-saturated conditions to study the effect of water on the differentiation of a basaltic andesite. The starting material was a mafic pumice from the compositionally zoned tuff deposited during the ~75 ka caldera-forming eruption of Newberry Volcano, a rear-arc...
Environmental correlates of temporary emigration for female Weddell seals and consequences for recruitment
Glenn E. Stauffer, Jay J. Rotella, Robert A. Garrott, William L. Kendall
2014, Ecology (95) 2526-2536
In colonial-breeding species, prebreeders often emigrate temporarily from natal reproductive colonies then subsequently return for one or more years before producing young. Variation in attendance–nonattendance patterns can have implications for subsequent recruitment. We used open robust-design multistate models and 28 years of encounter data for prebreeding female Weddell seals (Leptonychotes...
Supplemental feeding alters migration of a temperate ungulate
Jennifer D. Jones, Matthew Kauffman, Kevin L. Monteith, Brandon M. Scurlock, Shannon E. Albeke, Paul C. Cross
2014, Ecological Applications (24) 1769-1779
Conservation of migration requires information on behavior and environmental determinants. The spatial distribution of forage resources, which migration exploits, often are altered and may have subtle, unintended consequences. Supplemental feeding is a common management practice, particularly for ungulates in North America and Europe, and carryover effects on behavior of this...
Downscaled climate projections for the Southeast United States: evaluation and use for ecological applications
Adrienne Wootten, Kara Smith, Ryan Boyles, Adam Terando, Lydia Stefanova, Vasru Misra, Tom Smith, David L. Blodgett, Fredrick Semazzi
2014, Open-File Report 2014-1190
Climate change is likely to have many effects on natural ecosystems in the Southeast U.S. The National Climate Assessment Southeast Technical Report (SETR) indicates that natural ecosystems in the Southeast are likely to be affected by warming temperatures, ocean acidification, sea-level rise, and changes in rainfall and evapotranspiration. To better...
Shaking from injection-induced earthquakes in the central and eastern United States
Susan E. Hough
2014, Bulletin of the Seismological Society of America (104) 2619-2626
In this study I consider the ground motions generated by 11 moderate (Mw4.0-5.6) earthquakes in the central and eastern United States that are thought or suspected to be induced by fluid injection. Using spatially rich intensity data from the USGS “Did You Feel It?” system, I show that the...
Effects of disturbance and climate change on ecosystem performance in the Yukon River Basin boreal forest
Bruce K. Wylie, Matthew B. Rigge, Brian Brisco, Kevin Mrnaghan, Jennifer R. Rover, Jordan Long
2014, Remote Sensing (6) 9145-9169
A warming climate influences boreal forest productivity, dynamics, and disturbance regimes. We used ecosystem models and 250 m satellite Normalized Difference Vegetation Index (NDVI) data averaged over the growing season (GSN) to model current, and estimate future, ecosystem performance. We modeled Expected Ecosystem Performance (EEP), or anticipated productivity, in undisturbed...
Characterizing recent and projecting future potential patterns of mountain pine beetle outbreaks in the Southern Rocky Mountains
Lu Liang, Todd Hawbaker, Yanlei Chen, Zhi-Liang Zhu, Peng Gong
2014, Applied Geography (55) 165-175
The recent widespread mountain pine beetle (MPB) outbreak in the Southern Rocky Mountains presents an opportunity to investigate the relative influence of anthropogenic, biologic, and physical drivers that have shaped the spatiotemporal patterns of the outbreak. The aim of this study was to quantify the landscape-level drivers that explained the...
Can mercury in fish be reduced by water level management? Evaluating the effects of water level fluctuation on mercury accumulation in yellow perch (Perca flavescens)
James H. Larson, Ryan P. Maki, Brent C. Knights, Brian R. Gray
2014, Ecotoxicology (23) 1555-1563
Mercury (Hg) contamination of fisheries is a major concern for resource managers of many temperate lakes. Anthropogenic Hg contamination is largely derived from atmospheric deposition within a lake’s watershed, but its incorporation into the food web is facilitated by bacterial activity in sediments. Temporal variation in Hg content of fish...
Landbird trends in national parks of the North Coast and Cascades Network, 2005-12
James F. Saracco, Amanda L. Holmgren, Robert L. Wilkerson, Rodney B. Siegel, Robert C. Kuntz II, Kurt J. Jenkins, Patricia J. Happe, John R. Boetsch, Mark H. Huff
2014, Open-File Report 2014-1202
National parks in the North Coast and Cascades Network (NCCN) can fulfill vital roles as refuges for bird species dependent on late-successional forest conditions and as reference sites for assessing the effects of land-use and land-cover changes on bird populations throughout the larger Pacific Northwest region. Additionally, long-term monitoring of...
