The over-arching theme of this work is that soil data affect the performance and realism of vegetation models with particular focus on their ability to predict or explain disturbances such as fire or disease. We tested the sensitivity of the Excel version of the 3-PG model to soil properties and...
Soil-related problems common to Oregon farmers are
erosion, compaction, organic matter depletion, and
nutrient loss. High costs of fertilizer, fuel, and weed
control are additional management problems. Growing a
secondary crop as a living mulch with a primary crop may
ease some of these problems.
Sweet corn production in Oregon...
Plethodontid salamanders are diverse and widely distributed taxa and play critical roles in ecosystem processes. Due to salamander use of structurally complex habitats, and because only a portion of a population is available for sampling, evaluation of sampling designs and estimators is critical to provide strong inference about Plethodontid ecology...
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seventh author’s name. The correct name is: SummerPeterman. The
publisher apologizes for the error
Plethodontid salamanders are diverse and widely distributed taxa and play critical roles in ecosystem processes. Due to salamander use of structurally complex habitats, and because only a portion of a population is available for sampling, evaluation of sampling designs and estimators is critical to provide strong inference about Plethodontid ecology...
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,
Josh Johnson5, Summer Peerman5, Ben Brintz6, Michael Rochelle5
1 Weyerhaeuser, Federal Way, Washington
Correction
23 Dec 2015: The PLOS ONE Staff (2015) Correction: Evaluating Multi-Level Models to Test Occupancy State Responses of Plethodontid Salamanders. PLOS ONE 10(12): e0145899. https://doi.org/10.1371/journal.pone.0145899
Hatcheries whose purpose is to provide for a recreational fishery must minimize impacts on wild fishes. Management to reduce hatchery and wild interactions is especially important on river systems that contain Endangered Species Act (ESA) listed species. I examined adult hatchery summer steelhead, Oncorhynchus mykiss, behavior, current management and a...
Several evolutionarily significant units (ESUs) of Columbia River basin Chinook Salmon Oncorhynchus tshawytscha and Coho Salmon O. kisutch are listed as threatened or endangered under the U.S. Endangered Species Act. Yet little is known about the spatial and temporal distributions of these ESUs immediately following ocean entry, when year-class success...
Interannual variability in salmon (Oncorhynchus spp.) production in the northeast Pacific is understood to be driven by oceanographic variability and bottom-up processes affecting prey availability to juvenile salmon. Scyphozoan jellyfish have an important role in shaping the pathways of energy flow through pelagic food webs. While jellyfish obtain high production...
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Evidence that summer jellyfish blooms impact Pacific
Research on regulatory mechanisms in biological populations often focuses on environmental covariates. An integrated
approach that combines environmental indices with organismal-level information can provide additional insight on
regulatory mechanisms. Survival of spring/summer Snake River Chinook salmon (Oncorhynchus tshawytscha) is consistently
low whereas some adjacent populations with similar life histories experience...
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/summer Snake River Chinook salmon (Oncorhynchus tshawytscha) is consistently
low whereas some adjacent
Northern anchovy (Engraulis mordax) are a dominant forage fish in the California Current large marine ecosystem (CCLME). However, little is known about northern anchovy abundance, distribution, age structure, or population fluctuations relative to ocean conditions in the eastern boundary upwelling system off the U.S. West Coast. This thesis includes three...
The overall goal of this study was to identify multiple scales of habitat use and habitat electivity by redband/steelhead trout and define the limiting factors affecting the distribution patterns of this species during summer flows.
The main objective in chapter 2 was to identify the most important habitat associations that...
Generalized additive models (GAMs) were used to investigate the relationships between annual recruitment of natural coho salmon (Oncorhynchus kisutch) from Oregon coastal rivers and indices of the physical ocean environment. Nine indices were examined, ranging from large-scale ocean indicators, e.g., Pacific Decadal Oscillation (PDO), to indicators of the local ecosystem...
The community of trophically transmitted marine parasites of juvenile coho (Oncorhynchus kisutch) and Chinook
(Oncorhynchus tshawytscha) salmon across 8 years (2002–2009) was related to indices of physical and biological ocean conditions
and adult returns. When the biomass of lipid-poor, southern origin copepods in the coastal ocean was high during juvenile...
The growing demand for water in the arid regions of the West
increases the need for optimal allocation of water among competing
uses. An efficient allocation of water between instream and out-of-stream
uses has been impeded by institutional constraints and the
scarcity of information regarding instream flow benefits. The
objectives...
Juvenile coho salmon (101-400 mm) were sampled by
purse seine off the Pacific Coast from Waatch Point,
Washington to Four Mile Creek, Oregon, out to 30 mi
offshore, during the months of May, June, and September in
1982 and 1983. Sea surface temperature, surface salinity,
surface chlorophyll-a concentration, and Secchi...
Effects of the marine environment on age and size at maturity, early marine growth, and abundance of chum salmon, Oncorhynchus keta, were studied at Olsen Creek during 1959-77. Chum salmon returned to Olsen Creek as predominately 3-, 4-, and 5-year fish; however, age composition varied from year to year. The...
Rotary screw traps are used throughout the West Coast of North America to capture emigrating juvenile salmonids. Calibrating the capture efficiency of each trap is essential for valid estimates of fish passage. We released Passive Integrated Transponder (PIT) tagged Oncorhynchus mykiss upstream of a rotary screw trap in the South...
We examined variability in growth rate during the larval stage of northern anchovy (Engraulis mordax) in response to physical and biological environmental factors in 2005 and 2006. The onset of spring upwelling was anomalously delayed by 2–3 months until mid-July in 2005; in contrast, spring upwelling in 2006 began as...
A process-based forest growth model, 3-PG (Physiological Principles Predicting
Growth), parameterized with values of soil properties constrained by satellite-derived
estimates of maximum leaf area index (LAI[subscript max]), was run for Douglas-fir (Pseudotsuga
menziesii) to contrast the extent to which site growth potential might vary across western
North America between a...
A trophic model that simulates interactions between
a predatory fish (Pacific hake, Merluccius productus), forage
fish, and juvenile salmon off the Columbia River
was constructed to identify if trophic interactions could
account for marine mortality of Columbia River juvenile
salmon. The model estimates the number of juvenile
salmon that are...
Demographic characteristics of juvenile Dover sole
(Microstomus pacificus) were examined in relation to
physical and biotic factors to develop a hypothesis
explaining annual variations in recruitment. Surveys were
conducted along the Oregon continental shelf at depths
between 50-400 m bimonthly during 1989 and annually (in
March) between 1990 and 1993....
Processes of metamorphosis, settlement, and growth were examined in Pacific sanddab
using field studies and otolith microstructure. This flatfish transforms at large sizes, has a
gradual metamorphosis, and settles to a nursery on the middle continental shelf. Eye migration
takes 3 months and "metamorphosis proper" which begins after completion of...
The decline of many Pacific salmon stocks has stimulated interest in the early life history and habitat requirements of juvenile salmon. Although estuarine habitat associations of juvenile salmon have been investigated in many coastal areas of the eastern Pacific Ocean, until recently, little was known about juvenile salmonid ecology within...
This study was designed to provide information about the juvenile life history of coho salmon, Oncorhynchus kisutch, in the Tenmile Lakes in Oregon by 1) classifying scales of spawning fish and outgoing smolts (1+), 2) assessing the contribution of juvenile life history types to the returns of adults (3₂) and...
Concentrations of twenty-five PCBs, fifteen organochiorine pesticides and mercury were determined in recreational fish from the Willamette River, Oregon during the summer of 2000. Thirty-six fish samples of three fish species including black crappie, smalimouth bass and con-rn-ion carp were analyzed. The data reported here provides new information and recent...
The early marine phase following freshwater emigration has been identified as a critical period in salmonid (Oncorhynchus spp.) life history, characterized by high but variable mortality. Consistent with the “growth-mortality” and “bigger-is-better” hypotheses, at least some of the mortality during the critical period appears to be size-dependent – with smaller...
The Middle Fork John Day Basin in Northeastern Oregon is prime habitat for spring Chinook salmon and Steelhead trout. In 2008, a major tributary supporting rearing habitat, Big Boulder Creek, was restored to its historic mid-valley channel along a 1 km stretch of stream 800 m upstream of the mouth....
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of peak summer stream
temperatures was among the goals of the restoration. Using Distributed
Most marine fishes experience high rates of mortality during their early life history stages with far reaching consequences for adult population dynamics. Within a few weeks of hatching, relatively small changes in larval growth and mortality rates can lead to orders of magnitude variability in year-class strength. Growth and survival...
Small pelagic fishes (SPF), such as anchovies and sardines, are ecologically important due to their large abundance and intermediate trophic position that links plankton production to upper trophic levels. They are also economically important, supporting large fisheries that contribute to one fourth of the world fish landings. Reproductive success in...
Olympia oysters, “Ostrea conchaphila,” were once common along the west coast of North America. A popular delicacy, native oyster populations began to decline in the late 1800’s due to over‐harvest, degraded water quality, and habitat loss. Interest in re‐establishing the native oyster in a small Oregon estuary, Netarts Bay, culminated...
Corydalis aquae-gelidae is a large herbaceous perennial
in the Fumariaceae that has high habitat specificity. It is
endemic to the western Cascade Range of Oregon and
Washington, almost entirely on the Mt. Hood and Gifford
Pinchot National Forests. It is a federal C2 candidate
under the Endangered Species Act and...
Dramatic and ongoing changes pervading the Arctic and subarctic seas over
recent decades have motivated this effort to track and better understand hydrographic
variability using chemical tracers. Particular emphasis has been paid to differentiating
freshwater contributions to upper layers: namely Pacific water, meteoric water, and
sea-ice melt/formation.
Data collected in...
The movement characteristics of five landslides are
compared and interpreted based on records of approximately
10-years duration. Condon landslide in the Oregon Coast
Range has consistently exhibited brief (1 - 8 days) movement
episodes in wet winter months, separated by long periods of
no movement. The translatory movement is probably...
Salmonid run sizes are strongly affected by their early marine stage. Fully understanding the life history of salmonids means understanding how they interact with their marine environment and with other fishes. Changes in the biological and physical environment off the Columbia River region affects the distribution and abundance of predatory...
Recent research conducted throughout the Northern California Current (NCC) on the ecology of Pacific salmon (Oncorhynchus spp.) indicates that variable ocean conditions affect the community composition of zooplankton in the nearshore environment which, in turn, can affect the quality of prey for fish, sea birds and mammals. Interannual variability in...
Most modeling and statistical approaches encourage simplicity, yet ecological processes are often complex, as they are influenced by numerous dynamic environmental and biological factors. Pacific salmon abundance has been highly variable over the last few decades and most forecasting models have proven inadequate, primarily because of a lack of understanding...
The sustainable use of natural resources, including the goods and services provided by pasturelands and rangelands, is of growing importance due to climatic uncertainty and population growth. Maintaining high productivity in livestock operations is necessary as land availability diminishes and global populations rise. The potential negative impacts to the environment...
Fisheries economics is a recognized body of research
which is characterized by the joint study of economics,
the biological characteristics of fishery resources, and
the policies (regulations) used in the management of
fisheries. This thesis is composed of three papers,
each of which is primarily associated with one of the...
We investigated habitat use by juvenile Chinook salmon (Oncorhynchus tshawytscha) and coho salmon (O. kisutch) to identify environmental characteristics that may define their optimal marine habitat. We utilized physical and biological data from four cruises in the northern California Current system from Newport, Oregon, to Crescent City, California, in June...
Policy decisions in fishery management are becoming increasingly
complex and difficult. This is especially true for the salmon fisheries
where policy outcomes affect the productivity of the salmon
resource and the subsequent well-being of commercial fishermen, charter
boat operators, Indian fishermen, and sport anglers. The objective
of this study was...
We evaluated the relative importance of "bottom-up" (production-limited) and "top-down" (predator-mediated) processes during early marine residence in a population of Chinook salmon (Oncorhynchus tshawytscha) from the upper Columbia River, USA. We examined length, mass, and condition index of age-0 juveniles collected in the ocean during June and September across 11...
Dams, culverts, and water intake structures can impact the movement of aquatic and semi-aquatic species within streams and rivers. Datagaps exist regarding the impact of water intake structures on larval coastal giant salamanders (Dicamptodon tenebrosus) as these obstructions may produce a barrier to up and downstream movement. The Rock Creek...
In many animal species, males direct more intense courtship towards females they have not previously encountered,
than towards females with which they have previously mated. To test the factors responsible for this "Coolidge Effect", we need
studies on a wide range of taxa – including those with mating systems in...
Fisheries oceanography is the study of ecological relationships between fishes and the dynamics of their marine environments and aims to characterize the physical, chemical, and biological factors that affect the recruitment and abundance of harvested species. A recent push within the fisheries management community is toward ecosystem-based management. Here, we...
The Independent Multidisciplinary Science Team (IMST) was directed to evaluate the extent of predatory impacts of marine mammals and seabirds on salmonids and to recommend actions to mitigate impacts. IMST focused on the Oregon Department of Fisheries and Wildlife Action Plans because they provide the programmatic direction for the State...
A living mulch system consists of growing a regulated cover crop
with an economic crop. Living mulches are often interplanted with
horticultural crops, but competition for water can adversely affect
crop production. Various management practices may limit the negative
effects.
Studies were conducted for two purposes: (1) to determine if...
Investigation into how animals move within the landscape is important for both understanding of ecological processes and conservation management. Animal movement is important in shaping life history transitions, demographics, individual fitness, and species distributions. However, as landscapes become increasingly affected by human activities, movement becomes important as species navigate landscapes...