Browsing Fisheries by Title
Now showing items 138-157 of 238
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Migration and bioenergetics of juvenile Snake River fall Chinook salmon
(2012-08-10)While general patterns in the juvenile outmigration of Pacific salmon are well known, the proximate mechanisms informing migration in individuals are still poorly understood. This thesis describes a complex of individually-based ... -
Migration and Residence Patterns of Salmonids in Puget Sound, Washington
Diadromy is an unusual but widely distributed form of migration in fishes, and thus understanding these fishes requires a full knowledge of their behavior in both marine and freshwater environments. Freshwater ecology is ... -
Modeling Population Collapse and Recovery in Herring
Population collapse in forage fish occurs both naturally and due to overfishing, and is a challenge to sustainable fisheries management. Sustained low abundance can result in prolonged fishery closures and impact the ... -
Multispecies fisheries management in Japan’s offshore waters: the case of Hokkaido Pacific offshore trawl
Japan is currently implementing its reformed fisheries policy. The new Fisheries Act passed by the Diet in 2018 stipulates that output control through Total Allowable Catch (TAC) is the principle for fisheries resource ... -
Multispecies Management and Assessment in the US West Coast Groundfish Fishery
Multispecies fisheries are complex and present tradeoffs between ecological, economic, and social goals. Multispecies trawl fisheries, in which trawl gear is not easily able to select one species while avoiding others, ... -
Multispecies methods to facilitate the transition from heuristics to statistics in ecosystem-based fisheries management
Since 1985, fisheries management has undergone vast changes. Requests for new policies that evaluate impacts beyond individual removals of fish have outpaced the scientific tools available to implement them. Tools that ... -
Murky waters: discerning among sources of natural variation under high uncertainty and at multiple scales
Fresh waters account for an inordinately large portion of Earth’s carbon burial and methane production. As such, they are major components of energy flow within and between ecosystems. Yet, the roles of lakes and rivers ... -
Native and nonnative fish community and food-web dynamics in dryland streams of the American Southwest
Freshwater biodiversity is at once the most diverse and the most imperiled among the world’s ecosystems. In the southwest, regional biodiversity and endemism face challenges imposed by declining water availability and ... -
Nearshore larval fishes of Puget Sound
Puget Sound is home to about 220 fish species that produce pelagic larvae, however little is known about their early life history. Larval fishes were collected from the six basins (Rosario, Whidbey, Admiralty, Central, ... -
The non-lethal threat of hypoxia: ecological effects and physiological responses of estuarine species
Hypoxia [dissolved oxygen (DO) < 2 mg/L] is one of the key threats to some of the most productive regions of the marine environment (e.g., estuaries). Although mortality can occur, mobile organisms have the potential to ... -
Non-native species, size distributions, and nutrient recycling in southwestern stream communities
Non-native species introductions are a ubiquitous form of environmental change. However, the role of introductions in ecosystem functioning is still poorly understood, especially in highly invaded systems with multiple ... -
Nonanadromous Life History Diversity of Rainbow Trout (Oncorhynchus mykiss)
Rainbow trout (Oncorhynchus mykiss) is a salmonid species, native to Pacific Ocean drainages in North America and eastern Russia, which exhibits fluvial (stream-resident), adfluvial (lake-migrant), and anadromous (ocean-migrant) ... -
Ocean acidification and disease: How will a changing climate impact Vibrio tubiashii growth and pathogenicity to Pacific oyster larvae?
(2012-09-13)Vibrio tubiashii (Vt) is a causative agent of vibriosis in molluscan bivalves. Recent re-emergence of vibriosis in economically valuable shellfish, such as the Pacific oyster (Crassostrea gigas) in Washington State, has ... -
Ocean acidification influences on physiology and epigenetics in the Pacific oyster (Crassostrea gigas)
As ocean acidification continues to impact marine ecosystems at unprecedented rates, phenotypicplasticity may allow organisms to withstand more stressful conditions. Genomic methods can elucidate molecular mechanisms that ... -
Operational Harvest Control Rules and their Application to a Recovering Forage Fish Stock
Since the 1990s, international fisheries management has strived towards implementing precautionary management practices to reduce the risk of overfishing and subsequent stock collapse, and to promote rebuilding stocks from ... -
Overfishing or environmental change: Establishing the frequency of changes in productivity of marine fish stocks
(2013-07-25)The relative importance of environmental conditions and stock abundance in determining the productivity of fish stocks has been a subject of an on-going debate. The controversy can be formulated as four competing hypotheses: ... -
Parasites of the past: Tracking change in marine parasite abundance over time
In recent years, disease ecologists have perceived a dramatic increase in infectious-disease-related mass mortality events among marine organisms. But does this increase reflect an actual rise in rates of infectious disease, ... -
Partial Migration of Puget Sound Coho Salmon (Oncorhynchus kisutch) Individual and Population Level Patterns
(2013-11-14)Partial migration, the behavior pattern in which a portion of a population migrates while others do not, is a widespread phenomenon with ecological and evolutionary consequences. Most Coho Salmon (<italic>Oncorhynchus ... -
Patterns and ecological implications of small hydropower development in Brazil
The growing demand for renewable energy is fueling a global proliferation of Small Hydropower Plants (SHPs), which represents an emerging threat for freshwater ecosystems and aquatic biodiversity. The general perception ...