Capelin are a major component of cod diet in many ecosystems of the North Atlantic. In
the Bering Sea, however, the percentage of capelin found in Pacific cod stomachs is negligible. We
hypothesize that the landscape (or ‘seascape’) features of hydrography and bathymetry of the Bering
Sea impose a constraint...
Environmental variability is increasingly recognized as a primary determinant of year-class strength of marine fishes by directly or indirectly influencing egg and larval development, growth, and survival. Here we examined the role of annual water temperature variability in determining when and where walleye pollock (Theragra chalcogramma) spawn in the eastern...
Three successful vertical seismic profiles (VSPs) were acquired during
Ocean Drilling Program (ODP) Leg 204 at South Hydrate Ridge. The
data confirm earlier results from ocean bottom seismometer data and
analysis of moveout from common midpoint reflection data that the
average velocity between the seafloor and the bottom-simulating reflector
(BSR)...
Abundances of larval walleye pollock in Shelikof Strait, Gulf of Alaska, in 1981 were far
greater than any recorded estimates before that time or since (some patch estimates exceeded 100000
larvae per 10 m²). In spite of this extraordinary input, the ensuing 1981 year class was relatively poor.
An examination...
Despite the importance of habitat in determining species distribution and persistence, habitat dynamics are rarely modeled in studies of metapopulations. We used an integrated habitat-occupancy model to simultaneously quantify habitat change, site fidelity, and local colonization and extinction rates for larvae of a suite of Great Plains stream fishes in...
Climate can affect population dynamics in indirect ways via nonadditive forcing by external variables on internal demographic rates. Current analytical techniques, employed in population ecology, fail to explicitly include nonadditive interactions between internal and external variables, and therefore cannot efficiently address indirect climate effects. Here, we present the results of...
Climate regime shifts force fish communities through rapid transitions between alternate species assemblages, but little is known about the role that biochemical ecology plays in these transitions. We document a biochemical effect of climate-induced community transitions in boreal oceans: opposite population trajectories of lipid-rich and lipid-poor fish species. We compared...
There is growing evidence that climate and anthropogenic influences on marine ecosystems are largely manifested by changes in species spatial dynamics. However, less is known about how shifts in species distributions might alter predator-prey overlap and the dynamics of prey populations. We developed a general approach to quantify species spatial...
This paper presents a seismic sequence and structural analysis of a high-resolution three-dimensional seismic reflection survey that was acquired in June 2000 in preparation for Ocean Drilling Program (ODP) Leg 204. The seismic data were correlated with coring and logging results from nine sites drilled in 2002 during Leg 204....
Hydrate Ridge is an accretionary thrust ridge located on the lower slope of the central Cascadia convergent margin. Structural mapping based on two-dimensional and three-dimensional multichannel seismic reflection profiles and gridded bathymetry coupled with deep-towed sidescan sonar data and Ocean Drilling Program (ODP) biostratigraphy suggests that seafloor fluid venting patterns...
The implementation of US federal forest restoration programs on national forests is a complex process that requires balancing diverse socioecological goals with project economics. Despite both the large geographic scope and substantial investments in restoration projects, a quantitative decision support framework to locate optimal project areas and examine tradeoffs among...
We developed a hybrid cellular automata (CA) modelling approach to explore the dynamics of a key predator–prey interaction in a marine system; our study is motivated by the quest for better understanding of the scale and heterogeneity-related effects on the arrowtooth flounder (Atheresthes stomias) and walleye pollock (Theragra chalcogramma) dynamics...
This study examines potential interactions among the environmental variables likely to
affect larval walleye pollock Theragra chalcogramma feeding in the sea. Walleye pollock larvae were
sampled from Shelikof Strait, Gulf of Alaska, and from the eastern Bering Sea, with corresponding
environmental data. Variables used in our study were time spent...
Prediction of year-class strength is a critical challenge for fisheries managers. Theoretically,
predictions of recruitment should be better when they are based on estimates of cohort
size taken close to the age of recruitment and may improve if the effects of environmental factors
that influence pre-recruit mortality are accounted for....
In marine populations, spatial structure arises over a wide range of scales and forms
hierarchical aggregations. Changing spatial structure can alter the demographic and life history
trait variation within populations and subject individuals to both novel environmental conditions
and interspecific interactions. Thus, changes in the spatial structure of marine populations...
The subduction of the oceanic spreading center at the Chile Triple Junction is marked by a substantial thermal perturbation
and marked changes in the hydrogeologic and aqueous geochemical regimes in the overthrust plate. Ridge subduction substantially
changes the fluid chemistry in the wedge through variably hydrating the oceanic basement, accretionary...
Landforms are natural features on the Earth’s surface that both reflect and shape geophysical and ecological process. The result is a defining part of landscapes that so often impact on human perception and interactions with environment. Blascyznki (1997) defines landforms as, “specific geomorphic features on the surface of the Earth,...
The isotopic compositions of interstitial waters collected from Hydrate
Ridge during Ocean Drilling Program Leg 204 were measured to
evaluate the fluid evolution of this accretionary prism. At shallow
depths, the dissolved Cl- concentrations and δD and δ¹⁸O values of the
interstitial water reflect changes in the salinity and the...
A large-eddy simulation study was performed to characterize turbulence in sparse, row-oriented canopies. This was accomplished by simulating a set of heterogeneous row-oriented canopies with varying row vegetation density and spacing. To determine the effects of heterogeneity, results were compared to horizontally homogeneous canopies with an equivalent ‘effective’ leaf area...
In this article we consider the current educational needs for science and policy in marine resource management, and we propose a way to address them. The existing literature on cross-disciplinary education in response to pressing environmental problems is vast, particularly in conservation biology. However, actual changes in doctoral-level marine science...
A high-resolution primitive equation model simulation is used to form an energy budget for the principal semidiurnal tide (M₂) over a region of the Hawaiian Ridge from Niihau to Maui. This region includes the Kaena Ridge, one of the three main internal tide generation sites along the Hawaiian Ridge and...
With water vapor and clouds expected to effect significant feedbacks on climate, moisture transport through convective processes has important implications for future temperature change. The precipitation efficiency—the ratio of the rates at which precipitation and condensation form (e = P/C)—is useful for characterizing how much boundary layer moisture recycles through precipitation versus...
Let K be a cyclic number field of prime degree ℓ. Heilbronn showed that for a given ℓ there are only finitely many such fields that are norm-Euclidean. In the case of ℓ = 2 all such norm-Euclidean fields have been identified, but for ℓ ≠ 2, little else is...
Although there is acute concern that insect-caused tree mortality increases the likelihood or severity of subsequent wildfire, previous studies have been mixed, with findings typically based on stand-scale simulations or individual events. This study investigates landscape- and regional-scale wildfire likelihood following outbreaks of the two most prevalent native insect pests...
Although there is acute concern that insect‐caused tree mortality increases the likelihood or severity of subsequent wildfire, previous studies have been mixed, with findings typically based on stand‐scale simulations or individual events. This study investigates landscape‐ and regional‐scale wildfire likelihood following outbreaks of the two most prevalent native insect pests...
Although there is acute concern that insect‐caused tree mortality increases the likelihood or severity of subsequent wildfire, previous studies have been mixed, with findings typically based on stand‐scale simulations or individual events. This study investigates landscape‐ and regional‐scale wildfire likelihood following outbreaks of the two most prevalent native insect pests...
High‐resolution three‐dimensional (3‐D) seismic reflection data acquired on the R/V Thomas G. Thompson in 2000 reveal a pair of bottom simulating reflections (BSRs) across a broad region of southern Hydrate Ridge, offshore Oregon. The primary BSR (BSRp) is a regionally extensive reflection that lies 120–150 m below seafloor and exhibits...
With the recent advent of commercial laser absorption spectrometers, field studies measuring stable isotope ratios of hydrogen and oxygen in water vapor have proliferated. These pioneering analyses have provided invaluable feedback about best strategies for optimizing instrumental accuracy, yet questions still remain about instrument performance and calibration approaches for multi-year...
With the recent advent of commercial laser absorption spectrometers, field studies measuring stable isotope ratios of hydrogen and oxygen in water vapor have proliferated. These pioneering analyses have provided invaluable feedback about best strategies for optimizing instrumental accuracy, yet questions still remain about instrument performance and calibration approaches for multi-year...
Primula sect. Parryi comprises five species endemic to western North America: P. parryi, P. angustifolia, P. rusbyi, P. capillaris, and P. cusickiana with four varieties. This section, derived from a clade with representatives in Asia and Europe, exemplifies a phytogeographic pattern in which a widespread species is accompanied by multiple...
We conducted a comparative hazard assessment for 325,000 ha in a fire-prone area of southwest Oregon, USA. The landscape contains a variety of land ownerships, fire regimes, and management strategies. Our comparative hazard assessment evaluated the effects of two management strategies on crown fire potential and northern spotted owl (Strix...
Serotonin regulates many intestinal motor and sensory functions. Altered serotonergic metabolism has been described in human gastrointestinal diseases. The objective of our study was to compare expression of several components of the serotonergic system [serotonin (5-HT), serotonin reuptake transporter protein (SERT), tryptophan hydroxylase-1 (TPH-1), 5-HT receptor[subscript 2B] (5-HT[subscript 2B])] and...
We studied stand development in three distinct forest types in southwestern Oregon using six stands
each in uncut and clear-felled old-growth stands and nearby young stands (18 total). Old-growth stands
showed a wide range of tree ages (>300 years) and low tree densities for several centuries; rapid early
growth produced...
Many nurseries are considering soil moisture sensor networks to improve water application efficiency. Due to
the necessarily wide distribution of sensors at a nursery, a wireless network is easier to install, more flexible, and can be
scaled up as needed without re-design as compared to a traditional wired sensor network....
Mortality and injuries caused by ship strikes in U.S. waters are a cause of concern for the endangered population of blue whales (Balaenoptera musculus) occupying the eastern North Pacific. We sought to determine which areas along the U.S. West Coast are most important to blue whales and whether those areas...
We used spatial optimization to analyze alternative restoration scenarios and quantify tradeoffs for a large, multifaceted restoration program to restore resiliency to forest landscapes in the western US. We specifically examined tradeoffs between provisional ecosystem services, fire protection, and the amelioration of key ecological stressors. The results revealed that attainment...
Concentrated solar power (CSP) plants have the potential to reduce the consumption of nonrenewable resources and greenhouse gas emissions in electricity production. In CSP systems, a field of heliostats focuses solar radiation on a central receiver, and energy is then transferred to a thermal power plant at high temperature. However,...
Many multispecies models have assumed that prey density determines per-capita predator consumption rates, following a functional response relationship. However, empirical evidence suggests that a predator’s diet can also be influenced by a variety of environmental factors, including interactions with other predators. We used diet and abundance data from National Marine...
Context:
Functional connectivity—the facilitation of individual movements among habitat patches—is essential for species’ persistence in fragmented landscapes. Evaluating functional connectivity is critical for predicting range shifts, developing conservation plans, and anticipating effects of disturbance, especially for species affected by climate change.
Objectives:
We examined whether simplifying forest structure influenced animal...
Equilibrium climate sensitivity of the Community Climate System Model, version 4 (CCSM4) is 3.20 degrees C for 1 degrees horizontal resolution in each component. This is about a half degree Celsius higher than in the previous version (CCSM3). The transient climate sensitivity of CCSM4 at 1 degrees resolution is 1.72...
Predatorprey interactions are a primary structuring force vital to the resilience of marine communities and sustainability of the worlds oceans. Human influences on marine ecosystems mediate changes in species interactions. This generality is evinced by the cascading effects of overharvesting top predators on the structure and function of marine ecosystems....
Estimates of species' vital rates and an understanding of the factors affecting those parameters over time and space can provide crucial information for management and conservation. We used mark–recapture, reproductive output, and territory occupancy data collected during 1985–2013 to evaluate population processes of Northern Spotted Owls (Strix occidentalis caurina) in...
Engaging large numbers of undergraduates in authentic scientific discovery is desirable but difficult to achieve. We
have developed a general model in which faculty and teaching assistants from diverse academic institutions are trained to teach a
research course for first-year undergraduate students focused on bacteriophage discovery and genomics. The course...
The Manual on Uniform Traffic Control Devices (MUTCD) specifies minimum retroreflectivity
requirements that include an obligation for agencies to develop a strategy for maintaining
compliance. States were given a deadline of January 1, 2012 for the implementation of an
assessment or management plan, which led to an increased emphasis on...
With more than 407 species of freshwater and brackish water fishes, Gabon is a country rich in ichthyological biodiversity, but its aquatic environments remain poorly explored. We present and describe a new species of Enteromius, adding to the 16 species of Enteromius currently recorded from that country. This new species...
Forest management problems with even-flow and adjacency considerations are difficult to solve optimally. A heuristic search intensification process, which uses two types of decision procedures, changes to single-decision choices (1-opt moves) and changes to two-decision choices simultaneously (2-opt moves), was used in an attempt to locate feasible and efficient solutions...
The use of a reversion technique during the search process of s-metaheuristics has received little attention with respect to forest management and planning problems. Reversion involves the interruption of the sequence of events that are used to explore the solution space and the re-initiation of the search process from a...
Background:
Osteosarcoma (OS) is an aggressive and often fatal cancer that afflicts over 1000 humans and 10,000 dogs per year in the United States. Recent evidence suggests deregulation in the signaling triad, receptor activator of nuclear factor kappa B (RANK), its activating ligand (RANKL), and the RANKL inhibitor, osteoprotegerin (OPG)...
General circulation models (GCMs) predict that the global hydrological cycle will change in response to anthropogenic warming. However, these predictions remain uncertain, in particular, for precipitation (Intergovernmental Panel on Climate Change, 2013, https://doi .org/10.1017/CB09781107415324.004). Held and Soden (2006, https://doi.org/10.1175/JCLI3990.1) suggest that as lower tropospheric water vapor concentration increases in a...