Detecting persistent change in the habitat of salmon-bearing streams in the Pacific Northwest

2004 ◽  
Vol 61 (2) ◽  
pp. 283-291 ◽  
Author(s):  
David P Larsen ◽  
Philip R Kaufmann ◽  
Thomas M Kincaid ◽  
N Scott Urquhart
Keyword(s):  
Pacific Northwest ◽  
Pacific Salmon ◽  
Monitoring Network ◽  
Habitat Characteristics ◽  
Detection Sensitivity ◽  
Trend Detection ◽  
Spatial And Temporal Variation ◽  
The Pacific ◽  
Two Factors ◽  
Consistent Change

In the northwestern United States, there is considerable interest in the recovery of Pacific salmon (Oncorhynchus spp.) populations listed as threatened or endangered. A critical component of any salmon recovery effort is the improvement of stream habitat that supports various life stages. Two factors in concert control our ability to detect consistent change in habitat conditions that could result from significant expenditures on habitat improvement: the magnitude of spatial and temporal variation and the design of the monitoring network. We summarize the important components of variation that affect trend detection and explain how well-designed networks of 30–50 sites monitored consistently over years can detect underlying changes of 1–2% per year in a variety of key habitat characteristics within 10–20 years, or sooner, if such trends are present. We emphasize the importance of the duration of surveys for trend detection sensitivity because the power to detect trends improves substantially with the passage of years.

The Rationality of Mechanization in the Pacific Salmon-Canning Industry before the Second World War

1988 ◽  
Vol 62 (4) ◽  
pp. 626-655 ◽  
Author(s):  
Dianne Newell
Keyword(s):  
Pacific Northwest ◽  
Pacific Salmon ◽  
New Technology ◽  
Continuous Process ◽  
Second World War ◽  
Process Technology ◽  
The Pacific ◽  
Labor System ◽  
Canning Industry ◽  
Second World

An industry may fail to adopt or to extend new technology for many reasons other than lack of entrepreneurial vision. In the following article, Professor Newell considers the halting and incomplete diffusion of mechanization and continuous-process technology in the salmon-canning industry of the Pacific Northwest. She shows that the fragile and cyclical character of the natural resource, the labor system employed, and the remote and isolated locations of individual production units all affected cannery operators' decisions about technology adoption, and that the persistence of manual labor reflected rational, not reactionary, business choices.

scholarly journals Pathogens of Pacific Lamprey Detected Through Routine Fish Health Screenings

2019 ◽  
Vol 10 (2) ◽  
pp. 517-524 ◽  
Author(s):  
Jeffrey C. Jolley ◽  
Kenneth M. Lujan
Keyword(s):  
Pacific Northwest ◽  
Aeromonas Hydrophila ◽  
Vibrio Vulnificus ◽  
Conservation Management ◽  
Pacific Salmon ◽  
Specific Information ◽  
Fish Health ◽  
Fish Pathogens ◽  
Pacific Lamprey ◽  
The Pacific

Abstract Interest in conservation, management, and captive rearing of Pacific Lamprey Entosphenus tridentatus in the Pacific Northwest has risen in recent years. General and specific information regarding the occurrence of fish pathogens and the risk of Pacific Lamprey as a vector for pathogens to other species is not well understood. Specific efforts to captively rear or artificially propagate Pacific Lamprey at facilities that are used for Pacific salmon Oncorhynchus spp. have increased. We performed fish health surveys on wild-caught larval and adult Pacific Lamprey from locations that were used as lamprey sources for captive research to determine the occurrence of bacteria, viruses, and parasites that may be pathogens. A variety of potential pathogens was detected, most notably Aeromonas hydrophila and Vibrio vulnificus from larval Pacific Lamprey and A. salmonicida from adult lampreys. There was a general lack of pathogenic activity and absence of viral detections from all lampreys. The diversity of bacteria encountered from the larvae in our study could be indicative of the wide diversity of bacteria that is known to be associated with larval lamprey in general. Further efforts to understand pathogenic risk from Pacific Lamprey to salmonid propagation programs are warranted.

Do bears facilitate transfer of salmon resources to aquatic macroinvertebrates?

2005 ◽  
Vol 62 (10) ◽  
pp. 2285-2293 ◽  
Author(s):  
Monika Winder ◽  
Daniel E Schindler ◽  
Jonathan W Moore ◽  
Susan P Johnson ◽  
Wendy J Palen
Keyword(s):  
Pacific Northwest ◽  
Life Histories ◽  
Pacific Salmon ◽  
Stream Invertebrates ◽  
The Pacific ◽  
Salmon Carcass ◽  
Isotope Analyses ◽  
Long Term Survey ◽  
Spawning Habitats

In coastal areas of the Pacific Northwest bears (Ursus spp.) prey heavily on spawning Pacific salmon (Oncorhynchus spp.) and selectively kill energy-rich individuals that are the most recent arrivals on spawning grounds. Pacific salmon eventually die in spawning habitats anyway, albeit with considerably lower energetic content. We investigated whether foraging activities of bears facilitate growth of stream invertebrates by increasing the duration of salmon carcass availability and the nutritional value of carcasses for scavengers. Our survey in southwest Alaska showed that carcasses are highly colonized by caddisfly (Trichoptera) larvae. Caddisflies show a strong preference for bear-killed over senescent carcasses, which may be a result of extended temporal availability, improved accessibility of consumable tissue, and higher energetic content of bear-killed fish. Isotope analyses further indicate uptake of marine-derived nutrients in caddisflies during the salmon run, which, however, does not extend into subsequent generations. Thus, species with life histories linked to the annual marine derived nutrient pulse gain the biggest advantage from the salmon resource subsidy. A long-term survey in several creeks in this region showed that bear predation intensity varied greatly among creeks and years, therefore indirect effects of bear predation on aquatic scavengers are likely highly patchy in time and space.

Managing the decline of Pacific salmon: metapopulation theory and artificial recolonization as ecological mitigation

1999 ◽  
Vol 56 (9) ◽  
pp. 1700-1706 ◽  
Author(s):  
Kyle A Young
Keyword(s):  
Pacific Northwest ◽  
Fisheries Management ◽  
Habitat Restoration ◽  
Pacific Salmon ◽  
Habitat Destruction ◽  
The Pacific ◽  
The Face ◽  
Local Extinctions ◽  
Open Discussion ◽  
Metapopulation Theory

Pacific salmon (Oncorhynchus spp.) in the Pacific Northwest of North America have suffered regional declines and local extinctions primarily because of freshwater habitat destruction and overexploitation by fisheries. Management efforts to reverse this trend have correctly focused on habitat restoration and enhancement and stricter regulation of fisheries. Metapopulation theory and the ecology of the genus suggest that the addition of management efforts that artificially increase the rate of colonization of presently unoccupied habitats may promote the recovery and persistence of Pacific salmon in an ecologically realistic way. Such programs are conceptually and operationally different from traditional stock transfer and enhancement programs, which aimed to maintain a harvestable surplus of salmon in the face of habitat destruction and overfishing. I argue that artificial recolonization programs should be viewed as ecological mitigation, aimed at hastening the return of natural demographic and evolutionary processes, and hope here to promote an open discussion of their merits and risks as such.

Planetary mass, vegetation height and climate

2019 ◽  
Vol 18 (05) ◽  
pp. 477-482 ◽  
Author(s):  
David S. Stevenson
Keyword(s):  
Pacific Northwest ◽  
Climate Models ◽  
Tree Height ◽  
Lower Atmosphere ◽  
Maximum Height ◽  
Vegetation Height ◽  
Planetary Mass ◽  
The Pacific ◽  
Two Factors ◽  
The Impact

AbstractThe maximum height trees can grow on Earth is around 122–130 m. The height is constrained by two factors: the availability of water, and where water is not limiting, the pressure available to drive the column of water along the xylem vessels against the pull of gravity (cohesion tension). In turn the height of trees impacts the biodiversity of the environment in a number of ways. On Earth the largest trees are found in maritime temperate environments along the Pacific Northwest coasts of northern California and southern Oregon. These forests provide a large number of secondary habitats for species and serve as moisture pumps that return significant volumes of water to the lower atmosphere. In this work, we apply simple mathematical rules to illustrate how super-terran planets will have significantly smaller trees, with concomitant effects on the habitability of the planet. We also consider the impact of varying tree height on climate models.

Propagated Fish in Resource Management

2004 ◽  
Keyword(s):  
Pacific Northwest ◽  
Natural Population ◽  
Pacific Salmon ◽  
Monitoring And Evaluation ◽  
Wild Fish ◽  
Large Numbers ◽  
The Pacific ◽  
In Captivity ◽  
National Marine Fisheries Service

<em>Abstract.</em>—A number of stocks of anadromous salmonids in the Pacific Northwest are currently listed by the National Marine Fisheries Service (NOAA Fisheries) as threatened or endangered under the U.S. Endangered Species Act (ESA). The ESA recognizes that conservation of listed species may be facilitated by artificial propagation, including captive broodstocks, while factors impeding population recovery are identified and corrected. Captive broodstock programs differ from conventional salmon culture in that fish of wild origin are maintained in captivity throughout their life to produce offspring for the purpose of supplementing wild populations. The relatively short generation time (2–7 years) and potential to produce large numbers of offspring (1,500–5,000 eggs per female average, depending on the species) make Pacific salmon ideal for captive broodstock rearing. However, the technology is not without potential complications and risks. The paper presents guidelines to ensure a sound basis for implementation of captive broodstocks. Considerations must be based on overall knowledge of survival, reproductive success, and offspring fitness to accurately determine levels of risk in implementing a salmonid captive broodstock program. In general, use of captive broodstocks should be restricted to situations where the natural population is dangerously close to extinction. Proper precautions should be taken to minimize genetic impacts during the collection, mating, and rearing of captive broodstocks, as any alteration to the original genetic composition of the population in captivity may reduce the efficacy of supplementation in rebuilding the natural population. Furthermore, liberation of fish from captive broodstocks should be consistent with the known behavior of existing wild fish and on whatever knowledge is available of the life history characteristics of the wild fish. Because the benefits and risks have not been established through long-term monitoring and evaluation, captive broodstock development should be considered an experimental approach and used with caution.

Single-nucleotide polymorphism data describe contemporary population structure and diversity in allochronic lineages of pink salmon (Oncorhynchus gorbuscha)

2018 ◽  
Vol 75 (6) ◽  
pp. 987-997 ◽  
Author(s):  
Carolyn M. Tarpey ◽  
James E. Seeb ◽  
Garrett J. McKinney ◽  
William D. Templin ◽  
Alexander Bugaev ◽  
...  
Keyword(s):  
Population Structure ◽  
Pacific Northwest ◽  
Pacific Salmon ◽  
Pink Salmon ◽  
Oncorhynchus Gorbuscha ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Glacial Origin ◽  
The Pacific ◽  
Southcentral Alaska

Pink salmon, the most abundant Pacific salmon, have an obligate 2-year life cycle that leads to reproductively isolated even- and odd-year lineages. Using new and existing data, we examined the genetic structure of both lineages across their distributional range by genotyping 16 681 single-nucleotide polymorphisms for 383 individuals originating from seven pairs of even- and odd-year populations. Distinct differences in standing pools of genetic variation were identified between the lineages; we observed higher levels of heterozygosity, allelic richness, and significantly more private alleles in the odd-year lineage. However, the patterns of population structure were concordant between lineages: the Asian and northern Alaska populations displayed little differentiation but differed significantly from populations in southcentral Alaska and the Pacific Northwest. Our population structure results, in the context of known paleoecological information, suggest that both lineages occupied a northern Beringial refugium as well as a Cascadian refugium in North America during the Last Glacial Maximum. These results highlight the influence of historical patterns of habitat availability on contemporary population structure and support the hypothesis of a pre-glacial origin of the lineages.

scholarly journals Using a Species Distribution Approach to Model Historic Camas (Camassia quamash) in Southern Idaho and Implications for Foraging in the Late Archaic

2020 ◽  
Author(s):  
Royce Johnson
Keyword(s):  
Pacific Northwest ◽  
Species Distribution ◽  
Species Distribution Model ◽  
Diet Breadth ◽  
Habitat Characteristics ◽  
Distribution Model ◽  
Late Archaic ◽  
Human Diet ◽  
The Pacific ◽  
Suitable Habitats

Camas (Camassia quamash) is well documented as a traditional native food source throughout the Northwestern United States and Canada. A better understanding of the historic distribution of camas in Idaho would help to distinguish root foraging in this region from the Pacific Northwest. Modern grazing, development, climate change, and other factors have decimated native camas in this region. This study uses a species distribution model (MaxEnt) to provide a well-informed geospatial projection of the historic distribution and habitat characteristics of camas in Southern Idaho. Understanding the most significant landscape and climate characteristics for camas allows us to estimate suitable habitats, and therefore the potential influence of camas on human diet breadth and mobility in the Late Archaic.

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