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1.
Ambio ; 51(1): 280-290, 2022 Jan.
Article in English | MEDLINE | ID: mdl-33881758

ABSTRACT

This paper examines how residents of Southern Appalachia observe changes in their natural environment, the values that they assign to plants and animals in that environment, and their understandings and explanations of environmental change. We use semi-structured interviews and participant observation to determine that multigenerational residents and newcomers to the region are observing and noting change in different components of the environment and that they have different determinations of both the causes and likely consequences of that change. While multigenerational residents focus their observation and commentary on staple crops and culturally-important species, newcomers to the area concentrate on species related to recreational pursuits, giving each group insights into different aspects of environmental change. These findings are translated into recommendations for more inclusive and effective environmental and conservation planning.


Subject(s)
Conservation of Natural Resources , Knowledge , Animals , Appalachian Region , Crops, Agricultural , Humans
2.
Commun Biol ; 4(1): 222, 2021 02 18.
Article in English | MEDLINE | ID: mdl-33603119

ABSTRACT

Widespread declines in Atlantic and Pacific salmon (Salmo salar and Oncorhynchus spp.) have tracked recent climate changes, but managers still lack quantitative projections of the viability of any individual population in response to future climate change. To address this gap, we assembled a vast database of survival and other data for eight wild populations of threatened Chinook salmon (O. tshawytscha). For each population, we evaluated climate impacts at all life stages and modeled future trajectories forced by global climate model projections. Populations rapidly declined in response to increasing sea surface temperatures and other factors across diverse model assumptions and climate scenarios. Strong density dependence limited the number of salmon that survived early life stages, suggesting a potentially efficacious target for conservation effort. Other solutions require a better understanding of the factors that limit survival at sea. We conclude that dramatic increases in smolt survival are needed to overcome the negative impacts of climate change for this threatened species.


Subject(s)
Climate Change , Endangered Species , Life Cycle Stages , Salmon/growth & development , Animal Migration , Animals , Computer Simulation , Databases, Factual , Models, Theoretical , Population Dynamics
3.
PLoS One ; 15(9): e0238886, 2020.
Article in English | MEDLINE | ID: mdl-32997674

ABSTRACT

In 2015, the Pacific marine heat wave, low river flows, and record high water temperatures in the Columbia River Basin contributed to a near-complete failure of the adult migration of endangered Snake River sockeye salmon (Oncorhynchus nerka, NOAA Fisheries 2016). These extreme weather events may become the new normal due to anthropogenic climate change, with catastrophic consequences for endangered species. Existing anthropogenic pressures may amplify vulnerability to climate change, but these potential synergies have rarely been quantified. We examined factors affecting survival of endangered sockeye (Oncorhynchus nerka) and threatened Chinook salmon (O. tshawytscha) as they migrated upstream through eight dams and reservoirs to spawning areas in the Snake River Basin. Our extensive database included histories of 17,279 individual fish that migrated since 2004. A comparison between conditions in 2015 and daily temperatures and flows in a regulated basin forced by output from global climate models showed that 2015 did have many characteristics of projected future mean conditions. To evaluate potential salmon responses, we modeled migration timing and apparent survival under historical and future climate scenarios (2040s). For Chinook salmon, adult survival from the first dam encountered to spawning grounds dropped by 4-15%, depending on the climate scenario. For sockeye, survival dropped by ~80% from their already low levels. Through sensitivity analyses, we observed that the adult sockeye migration would need to shift more than 2 weeks earlier than predicted to maintain survival rates typical of those seen during 2008-2017. Overall, the greater impacts of climate change on adult sockeye compared with adult Chinook salmon reflected differences in life history and environmental sensitivities, which were compounded for sockeye by larger effect sizes from other anthropogenic factors. Compared with Chinook, sockeye was more negatively affected by a history of juvenile transportation and by similar temperatures and flows. The largest changes in temperature and flow were projected to be upstream from the hydrosystem, where direct mitigation through hydrosystem management is not an option. Unfortunately, Snake River sockeye have likely lost much of their adaptive capacity with the loss of the wild population. Further work exploring habitat restoration or additional mitigation actions is urgently needed.


Subject(s)
Animal Migration/physiology , Oncorhynchus/classification , Animal Migration/classification , Animals , Climate Change , Conservation of Natural Resources , Endangered Species , Idaho , Oncorhynchus/growth & development , Oncorhynchus/physiology , Oregon , Rivers , Washington
4.
Proc Natl Acad Sci U S A ; 117(14): 7665-7671, 2020 04 07.
Article in English | MEDLINE | ID: mdl-32205439

ABSTRACT

Climate change is likely to change the relationships between commonly used climate indices and underlying patterns of climate variability, but this complexity is rarely considered in studies using climate indices. Here, we show that the physical and ecological conditions mapping onto the Pacific Decadal Oscillation (PDO) index and North Pacific Gyre Oscillation (NPGO) index have changed over multidecadal timescales. These changes apparently began around a 1988/1989 North Pacific climate shift that was marked by abrupt northeast Pacific warming, declining temporal variance in the Aleutian Low (a leading atmospheric driver of the PDO), and increasing correlation between the PDO and NPGO patterns. Sea level pressure and surface temperature patterns associated with each climate index changed after 1988/1989, indicating that identical index values reflect different states of basin-scale climate over time. The PDO and NPGO also show time-dependent skill as indices of regional northeast Pacific ecosystem variability. Since the late 1980s, both indices have become less relevant to physical-ecological variability in regional ecosystems from the Bering Sea to the southern California Current. Users of these climate indices should be aware of nonstationary relationships with underlying climate variability within the historical record, and the potential for further nonstationarity with ongoing climate change.


Subject(s)
Climate Change , Atmosphere , Pacific Ocean
5.
Glob Public Health ; 14(6-7): 884-898, 2019.
Article in English | MEDLINE | ID: mdl-29869560

ABSTRACT

Under President Rafael Correa (2007-2017), Ecuador's Ministry of Health established a state-centred health care regime that incorporates elements of Latin American social medicine into post-neoliberalism. These initiatives - which are part of 'The National Plan for Good Living (Buen Vivir)' - include free healthcare, greater attention to social determinants of health, a focus on equity and inclusion, and increased coordination across welfare, health, and development sectors. However, the reforms also use health services to build a sense of inclusive, participatory citizenship, with the Ecuadorean state as the central figure in service provision. In this paper, we demonstrate that state-centred health care reforms have paradoxically weakened community organising for collective health. Drawing on seventeen years of ethnographic research and health solidarity work in rural Northwest Ecuador, we illustrate how Ecuador's health reforms have reconfigured relations among local civil society, transnational NGOs, and the state. Established modes of community participation and international collaboration have been undermined largely because these reforms ignore community sovereignty and self-organisation and overemphasise the threat of neoliberalism. The lessons about balancing the state-based fulfilment of rights with community power are relevant to social medicine advocates, particularly those working in rural communities that are already organising creatively for their own health and well-being.


Subject(s)
Community Participation , Health Care Reform , Health Policy , Politics , Social Medicine , Ecuador , Humans , Internationality , Rural Health
6.
Sci Rep ; 7(1): 15439, 2017 11 20.
Article in English | MEDLINE | ID: mdl-29158502

ABSTRACT

Many marine mammal predators, particularly pinnipeds, have increased in abundance in recent decades, generating new challenges for balancing human uses with recovery goals via ecosystem-based management. We used a spatio-temporal bioenergetics model of the Northeast Pacific Ocean to quantify how predation by three species of pinnipeds and killer whales (Orcinus orca) on Chinook salmon (Oncorhynchus tshawytscha) has changed since the 1970s along the west coast of North America, and compare these estimates to salmon fisheries. We find that from 1975 to 2015, biomass of Chinook salmon consumed by pinnipeds and killer whales increased from 6,100 to 15,200 metric tons (from 5 to 31.5 million individual salmon). Though there is variation across the regions in our model, overall, killer whales consume the largest biomass of Chinook salmon, but harbor seals (Phoca vitulina) consume the largest number of individuals. The decrease in adult Chinook salmon harvest from 1975-2015 was 16,400 to 9,600 metric tons. Thus, Chinook salmon removals (harvest + consumption) increased in the past 40 years despite catch reductions by fisheries, due to consumption by recovering pinnipeds and endangered killer whales. Long-term management strategies for Chinook salmon will need to consider potential conflicts between rebounding predators or endangered predators and prey.


Subject(s)
Environmental Restoration and Remediation/statistics & numerical data , Fisheries/statistics & numerical data , Food Chain , Salmon/physiology , Animals , Biomass , Endangered Species/statistics & numerical data , Endangered Species/trends , Environmental Restoration and Remediation/trends , Fisheries/trends , Pacific Ocean , Phoca/physiology , Population Dynamics , Predatory Behavior/physiology , Sea Lions/physiology , Whale, Killer/physiology
7.
Ecosphere ; 8(12): 1-23, 2017 Dec 22.
Article in English | MEDLINE | ID: mdl-29552374

ABSTRACT

It is generally accepted that climate change will stress coldwater species like Pacific salmon. However, it is unclear what aspect of altered thermal regimes (e.g., warmer winters, springs, summers, or increased variability) will have the greatest effect, and what role the spatial properties of river networks play. Thermally diverse habitats may afford protection from climate change by providing opportunities for aquatic organisms to find and use habitats with optimal conditions for growth. We hypothesized that climate-altered thermal regimes will change growth and timing of life history events such as emergence or migration but that changes will be moderated in topologically complex stream networks where opportunities to thermoregulate are more readily available to mobile animals. Because climate change effects on populations are spatially variable and contingent upon physiological optima, assessments of risk must take a spatially explicit approach. We developed a spatially-structured individual based model for Chinook Salmon (Oncorhynchus tshawytscha) in which movement decisions and growth were governed by water temperature and conspecific density. We evaluated growth and phenology (timing of egg emergence and smolting) under a variety of thermal regimes (each having a different minimum, rate of warming, maximum, and variability) and in three network shapes of increasing spatial complexity. Across networks, fish generally grew faster and were capable of smolting earlier in warmer scenarios where water temperatures experienced by fish were closer to optimal; however, growth decreased for some fish. We found that salmon size and smolt date responded more strongly to warmer springs and summers than to warmer winters or increased variability. Fish in the least complex network grew faster and were ready to smolt earlier than fish in the more spatially complex network shapes in the contemporary thermal regime; patterns were similar but less clear in warmer thermal regimes. Our results demonstrate that network topology may influence how fish respond to thermal landscapes, and this information will be useful for incorporating a spatiotemporal context into conservation decisions that promote long-term viability of salmon in a changing climate.

8.
PLoS One ; 8(1): e54134, 2013.
Article in English | MEDLINE | ID: mdl-23326586

ABSTRACT

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 of the processes affecting variability in survival. Better methods and data for predicting the abundance of returning adults are therefore required to effectively manage the species. We combined 31 distinct indicators of the marine environment collected over an 11-year period into a multivariate analysis to summarize and predict adult spring Chinook salmon returns to the Columbia River in 2012. In addition to forecasts, this tool quantifies the strength of the relationship between various ecological indicators and salmon returns, allowing interpretation of ecosystem processes. The relative importance of indicators varied, but a few trends emerged. Adult returns of spring Chinook salmon were best described using indicators of bottom-up ecological processes such as composition and abundance of zooplankton and fish prey as well as measures of individual fish, such as growth and condition. Local indicators of temperature or coastal upwelling did not contribute as much as large-scale indicators of temperature variability, matching the spatial scale over which salmon spend the majority of their ocean residence. Results suggest that effective management of Pacific salmon requires multiple types of data and that no single indicator can represent the complex early-ocean ecology of salmon.


Subject(s)
Animal Migration/physiology , Fisheries , Salmon/physiology , Animals , Ecosystem , Environment , Pacific Ocean , Rivers , Seasons
9.
PLoS One ; 8(12): e85586, 2013.
Article in English | MEDLINE | ID: mdl-24392020

ABSTRACT

Thermal layering in reservoirs upstream from hydroelectric dams can create temperature gradients in fishways used by upstream migrating adults. In the Snake River, Washington, federally-protected adult salmonids (Oncorhynchus spp.) often encounter relatively cool water in dam tailraces and lower ladder sections and warmer water in the upstream portions of ladders. Using radiotelemetry, we examined relationships between fish passage behavior and the temperature difference between the top and bottom of ladders (∆T) at four dams over four years. Some spring Chinook salmon (O. tshawytscha) experienced ∆T ≥ 0.5 °C. Many summer and fall Chinook salmon and summer steelhead (O. mykiss) experienced ∆T ≥ 1.0 °C, and some individuals encountered ΔT > 4.0°C. As ΔT increased, migrants were consistently more likely to move down fish ladders and exit into dam tailraces, resulting in upstream passage delays that ranged from hours to days. Fish body temperatures equilibrated to ladder temperatures and often exceeded 20°C, indicating potential negative physiological and fitness effects. Collectively, the results suggest that gradients in fishway water temperatures present a migration obstacle to many anadromous migrants. Unfavorable temperature gradients may be common at reservoir-fed fish passage facilities, especially those with seasonal thermal layering or stratification. Understanding and managing thermal heterogeneity at such sites may be important for ensuring efficient upstream passage and minimizing stress for migratory, temperature-sensitive species.


Subject(s)
Animal Migration , Oncorhynchus mykiss , Temperature , Animals , Rivers/chemistry , Time Factors , Water/chemistry
10.
Lat Am Perspect ; 37(6): 30-52, 2010.
Article in English | MEDLINE | ID: mdl-20976980

ABSTRACT

Cooperatives and socially responsible corporations are being hailed as possible correctives to the socioeconomic and ecological exploitation of transnational capitalism. AmazonCoop­a cooperative linking indigenous Brazil nut harvesters and the multinational firm The Body Shop through trade and development projects­capitalized on indigenous symbolism to generate significant material benefits for both parties. At the same time, however, it made indigenous people more vulnerable and dependent, failed to promote participatory development, masked the effects of unfavorable state policies, and perpetuated discriminatory distinctions among indigenous people. Furthermore, the cooperative did not provide an organizational framework to ameliorate the vulnerabilities of indigenous identity politics or transform symbolic capital into enduring political-economic change. This case strongly supports arguments that cooperatives must be rooted in participation, democratic member control, and autonomy if they are to promote "fair globalization" or social transformation rather than institutionalize existing patterns of exploitation.


Subject(s)
Conservation of Natural Resources , Indians, South American , Internationality , Public Health , Social Responsibility , Socioeconomic Factors , Brazil/ethnology , Conservation of Natural Resources/economics , Conservation of Natural Resources/history , Conservation of Natural Resources/legislation & jurisprudence , Cooperative Behavior , History, 20th Century , History, 21st Century , Humans , Indians, South American/education , Indians, South American/ethnology , Indians, South American/history , Indians, South American/legislation & jurisprudence , Indians, South American/psychology , Internationality/history , Public Health/economics , Public Health/education , Public Health/history , Public Health/legislation & jurisprudence , Quality of Life/legislation & jurisprudence , Quality of Life/psychology , Social Conditions/economics , Social Conditions/history , Social Conditions/legislation & jurisprudence , Socioeconomic Factors/history
11.
Ecol Appl ; 18(1): 246-57, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18372570

ABSTRACT

Catastrophic die-offs can have important consequences for vertebrate population growth and biodiversity, but catastrophic risks are not commonly incorporated into endangered-species recovery planning. Natural (e.g., landslides, floods) and anthropogenic (e.g., toxic leaks and spills) catastrophes pose a challenge for evolutionarily significant units (ESUs) of Pacific salmon listed under the Endangered Species Act and teetering at precariously low population levels. To spread risks among Puget Sound chinook salmon populations, recovery strategies for ESU-wide viability recommend at least two viable populations of historical life-history types in each of five geographic regions. We explored the likelihood of Puget Sound chinook salmon ESU persistence by examining spatial patterns of catastrophic risk and testing ESU viability recommendations for 22 populations of the threatened Puget Sound chinook salmon ESU. We combined geospatial information about catastrophic risks and chinook salmon distribution in Puget Sound watersheds to categorize relative catastrophic risks for each population. We then analyzed similarities in risk scores among regions and compared risk distributions among strategies: (1) population groups selected using the ESU viability recommendations of having populations spread out geographically and including historical life-history diversity, and (2) population groups selected at random. Risks from individual catastrophes varied among populations, but overall risk from catastrophes was similar within geographic regions. Recovery strategies that called for two viable populations in each of five geographic regions had lower risk than random strategies; strategies that included life-history diversity had even lower risks. Geographically distributed populations have varying catastrophic-risks profiles, thus identifying and reinforcing the spatial and life-history diversity critical for populations to respond to environmental change or needed to rescue severely depleted or extirpated populations. Recovery planning can promote viability of Pacific salmon ESUs across the landscape by incorporating catastrophic risk assessments.


Subject(s)
Conservation of Natural Resources , Salmon , Animals , Risk Assessment , Washington , Water Pollutants, Chemical/toxicity
12.
Ecology ; 87(9): 2366-77, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16995637

ABSTRACT

The outcome of predation interactions between growing, size-structured predator and prey cohorts is difficult to predict. We manipulated the food resources available to juvenile spot subject to predation from southern flounder in a 60-day replicated pond experiment to test the hypothesis that spot growing slowly would experience higher predation mortality and stronger selection against small individuals than those growing rapidly. A nearly threefold difference in average growth rate between fast- and slow-growth treatments led to twofold higher predation mortality of slow-growing spot. Relative to no-flounder controls, larger spot were overrepresented at the end of the experiment in both treatments, but the magnitude of flounder size selection was much greater in the slow-growth treatment. The experimental results agreed qualitatively, but not quantitatively, with predictions from a prior size-dependent foraging model. In particular, the model significantly underestimated observed shifts in spot size structure to larger sizes. We hypothesized that competitive release and associated increases in spot growth due to thinning by flounder might reconcile this difference, and extended the model to incorporate this process. We then used the model to estimate the relative contribution of these two confounded predator effects (size-selective predation and thinning) to observed shifts in spot size structure. Model simulations indicated that the combined effects of size-selective predation and thinning could account for nearly all of the observed shift in spot size structure, but that thinning was the more important process. Our results highlight the utility of combining experimental and modeling approaches to unravel the complexities underlying interactions between growing, size-structured predator and prey cohorts.


Subject(s)
Body Size/physiology , Flatfishes/physiology , Models, Biological , Perciformes/growth & development , Predatory Behavior/physiology , Animals , Computer Simulation , Population Density , Random Allocation
13.
Radiographics ; 25(6): 1591-607, 2005.
Article in English | MEDLINE | ID: mdl-16284137

ABSTRACT

Rotator cuff tears are a common cause of shoulder pain. Clinical and radiographic findings can suggest the presence of a rotator cuff tear. The most sensitive clinical findings are impingement and the "arc of pain" sign. Radiographic findings are usually normal in the acute setting, although the "active abduction" view may show decreased acromiohumeral distance. In more chronic cases, an outlet view may show decreased opacity and decreased size of the supraspinatus muscle due to atrophy. In late cases, the humeral head may become subluxated superiorly, and secondary degenerative arthritis of the glenohumeral joint may ensue. Ultrasonography (US), with over 90% sensitivity and specificity, can help confirm the diagnosis in clinically or radiographically equivocal cases. US can also reveal the presence of other abnormalities that may mimic rotator cuff tear at clinical examination, including tendinosis, calcific tendinitis, subacromial subdeltoid bursitis, greater tuberosity fracture, and adhesive capsulitis.


Subject(s)
Rotator Cuff Injuries , Rotator Cuff/diagnostic imaging , Diagnosis, Differential , Humans , Magnetic Resonance Imaging , Radiography , Rotator Cuff/pathology , Ultrasonography
14.
Anal Chem ; 75(8): 1786-91, 2003 Apr 15.
Article in English | MEDLINE | ID: mdl-12713034

ABSTRACT

This paper describes a microfabricated enzyme assay system including a micromixer that can be used to perform stopped-flow reactions. Samples and reagents were transported into the system by electroosmotic flow (EOF). Streams of reagents were merged and passed through the 100-pL micromixer in < 1 s. The objective of the work was to perform kinetically based enzyme assays in the stopped-flow mode using a system of roughly 6 nL volume. Beta-galactosidase (beta-Gal) was chosen as a model enzyme for these studies and was used to convert the substrate fluorescein mono-beta-D-galactopyranoside (FMG) into fluorescein. Results obtained with microfabricated systems using the micromixer compared well to those obtained with an external T mixing device. In contrast, assays performed in a microfabricated device by merging two streams and allowing mixing to occur by lateral diffusion did not compare well. Using the microfabricated mixer, Km and kcat values of 75 +/- 13 microM and 44 +/- 3 s(-1) were determined. These values compare well to those obtained with the conventional stopped-flow apparatus for which Km was determined to be 60 +/- 6 microM and kcat was 47 +/- 4 s(-1). Enzyme inhibition assays with phenylethyl-beta-D-thiogalactoside (PETG) were also comparable. It was concluded that kinetically based, stopped-flow enzyme assays can be performed in 60 s or less with a miniaturized system of roughly 6 nL liquid volume when mixing is assisted with the described device.


Subject(s)
Clinical Enzyme Tests/instrumentation , Clinical Enzyme Tests/methods , Equipment Design , Kinetics , Microchemistry/instrumentation , beta-Galactosidase/analysis , beta-Galactosidase/metabolism
15.
J Am Chem Soc ; 125(30): 9111-5, 2003 Jul 30.
Article in English | MEDLINE | ID: mdl-15369368

ABSTRACT

Macromolecular interactions were demonstrated to yield large chiroptical effects in second harmonic generation measurements of ultrathin surface films. Second harmonic generation (SHG) has recently shown to be several orders of magnitude more sensitive to chirality in oriented systems than common linear methods, including absorbance circular dichroism (CD) and optical rotary dispersion (ORD). Numerous mechanisms have been developed to explain this anomalous sensitivity, with a general emphasis on understanding the molecular origins of the chromophore chirality. In this work, orientational effects alone are shown to be the dominant factor for generating large SHG chiral dichroic ratios in many surface systems. Three distinct uniaxial surface films of SHG-active achiral chromophores oriented at chiral templated surfaces were observed to yield chiral dichroic ratios as great as 40% in magnitude.

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