Browsing Fisheries by Title
Now showing items 98-117 of 238
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Hatcheries, phenology, and families: Juvenile steelhead ecology in Forks Creek, Washington
(2014-04-30)Juvenile ecology can affect subsequent population dynamics. This work focuses on two aspects of juvenile steelhead (Oncorhynchus mykiss) ecology: 1) tradeoffs between naturally-spawned hatchery and wild fish, and 2) the ... -
Hierarchical models of fishing behavior by factory trawlers in midwater-trawl fishery for Pacific hake (Merluccius productus)
(1998)The fishing behavior of factory trawlers in the Pacific hake (Merluccius productus) fishery at different spatio-temporal scales was studied using several modeling techniques. In Chapter 1, a Markov decision process model ... -
History and extent of introgressive hybridization in Puget Sound rockfishes (Sebastes auriculatus, S. caurinus, and S. maliger)
(2013-02-25)Natural hybridization is common in closely related species especially where they invade novel habitat. The patterns of introgressive hybridization are often asymmetrical and are attributed to various influences from selection ... -
How fish cope in a world of feast and famine: behavioral and physiological adaptations to ecological heterogeneity
(2013-04-17)Predator-prey interactions are patchy in space and time due to a variety of interactions between predator behavior, prey behavior, and landscape heterogeneity. To survive in a patchy world, predators must capitalize on ... -
Ichthyophonus in Pacific herring: Investigating a transmission hotspot
Chapter 1. Sample collection and processing methods were optimized and validated for the detection of Ichthyophonus DNA in environmental samples using both spiked and field samples. Methods performance testing revealed low ... -
Identifying shifts in maternity den phenology and habitat characteristics of polar bears (Ursus maritimus) in Baffin Bay and Kane Basin
The phenology and habitat selection of polar bear (Ursus maritimus) maternity dens may change over time in response to shifting environmental conditions. This study compared satellite telemetry data on 40 adult females ... -
Impact of Ocean Acidification on Recruitment and Yield of Bristol Bay Red King Crab
(2013-07-23)The excess of anthropogenic carbon dioxide (CO2) produced since the industrial revolution is being absorbed by the oceans through the carbon cycle. Atmospheric carbon dioxide has increased about 40% since the preindustrial ... -
Impacts of temperature on the molecular response of shellfish
Climate change is causing the average global ocean temperature to increase. In the face of ocean warming, the majority of marine organisms will be impacted by this shift in thermal regimes. There will likely be some species, ... -
Implications of climate change for strategic conservation and restoration of tidal wetlands in the U.S. portion of the Salish Sea
Coastal ecosystems are potentially at risk of sea level rise and other accelerated changes in climate. The overall goal of this thesis was to explore the potential influences of spatially varied climate change impacts on ... -
Implications of demographic diversity for forage fish, their fisheries, and ecosystems
Forage fish play a key role in marine ecosystems and fisheries worldwide. They are highly productive, and undergo dramatic fluctuations in productivity, which interact with fishing pressure and spatial dynamics to generate ... -
Implications of Environmental and Landscape Change for Population Connectivity and the Persistence of Aridland Amphibians
The study of how population structure and persistence are shaped by attributes of species and the environment is a central scientific pursuit in ecology and conservation. In this dissertation, I explore four themes central ... -
Inbreeding and its consequences for genetic variation and early life history in chinook salmon
(2001)As a necessary background for my experimental studies, I reviewed inbreeding and its consequences and the relationship between genetic variability and fitness in salmonid fishes. Inbreeding directly reduces individual ... -
Incorporating an otolith-derived environmental index into growth for stock assessment models
Growth is one of the key demographic processes for population dynamics. There is a growing body of literature showing that growth in fish is plastic over time, and affected by climate variability. However, time-varying ... -
Incorporating model selection and decision analysis into population dynamics modeling
(2006)Model selection tools are an integral part of biological inference. However, with the advent of recent software packages, researchers may be placing less thought into model selection uncertainty. After reviewing the existing ... -
Influence of early life growth and precipitation zone on survival to adulthood in wild Steelhead Trout (Oncorhynchus mykiss) in the Skagit River basin, WA
(2013-11-14)Wild Steelhead Trout, Oncorhynchus mykiss, in the Puget Sound are currently in decline, and very little is known about the early life history of these threatened fish. This study evaluated consequences of early life growth ... -
The influence of individual transferable quotas on discarding and fishing behavior in multispecies fisheries
(2004)Under individual transferable quotas (ITQs), participants receive a share of the total allowable catch (TAC), can choose when to fish, and can sell or lease their share. ITQs generally increase fishing flexibility, improve ... -
Influence of Juvenile and Adult Experiences on Tributary Overshoot and Fallback by Steelhead in the Columbia River Basin
Tributary overshoot occurs when adult fishes homing to natal sites continue upstream past the mouth of their natal stream. Using multistate release-recapture models, I examined the prevalence of overshooting and fallback ... -
Influence of urbanization on the health of juvenile salmonids in Pacific Northwest perennial streams
Increasing population and urbanization leads to stress in freshwater systems from a variety of anthropogenic influences including structural changes to habitat, temperature effects from increased runoff and reduced canopy ... -
Influences of beaver (Castor canadensis) activity on ecology and fish assemblages of dryland streams
(2014-02-24)After near-extirpation in the early 20th century, beaver populations are increasing throughout many parts of North America. Simultaneously, there is an emerging interest in employing beaver activity for stream restoration ... -
Information transfer, heterogeneity, and local environmental effects on emergent group patterns defining fish schools: perspectives from different scales of observation
It is widely understood why animals group, but much less is known about how animals group. Not all group structure provides functional benefit to the individuals therein; however, those group structures that do provide ...