Reducing River Flows to Control a Parasitic Salmonid Disease in the Klamath River: Simulations Question the Efficacy of Desiccation as a Management Tool

2021 ◽  
Author(s):  
Aaron Turecek ◽  
Quinn Payton ◽  
Julie D. Alexander ◽  
Damon Goodman ◽  
Allen F. Evans ◽  
...  
Keyword(s):  
Management Tool ◽  
River Flows ◽  
Klamath River

scholarly journals Density of the Waterborne Parasite Ceratomyxa shasta and Its Biological Effects on Salmon

2012 ◽  
Vol 78 (10) ◽  
pp. 3724-3731 ◽  
Author(s):  
Sascha L. Hallett ◽  
R. Adam Ray ◽  
Charlene N. Hurst ◽  
Richard A. Holt ◽  
Gerri R. Buckles ◽  
...  
Keyword(s):  
Parasite Density ◽  
Water Samples ◽  
Oncorhynchus Tshawytscha ◽  
Biological Effects ◽  
Monitoring Program ◽  
Management Tool ◽  
Degree Days ◽  
Content Type ◽  
Klamath River ◽  
Specific Parasite

ABSTRACTThe myxozoan parasiteCeratomyxa shastais a significant pathogen of juvenile salmonids in the Pacific Northwest of North America and is limiting recovery of Chinook (Oncorhynchus tshawytscha) and coho (O. kisutch) salmon populations in the Klamath River. We conducted a 5-year monitoring program that comprised concurrent sentinel fish exposures and water sampling across 212 river kilometers of the Klamath River. We used percent mortality and degree-days to death to measure disease severity in fish. We analyzed water samples using quantitative PCR and Sanger sequencing, to determine total parasite density and relative abundance ofC. shastagenotypes, which differ in their pathogenicity to salmonids. We detected the parasite throughout the study zone, but parasite density and genetic composition fluctuated spatially and temporally. Chinook and coho mortality increased with density of their specific parasite genotype, but mortality-density thresholds and time to death differed. A lethality threshold of 40% mortality was reached with 10 spores liter−1for Chinook but only 5 spores liter−1for coho. Parasite density did not affect degree-days to death for Chinook but was negatively correlated for coho, and there was wider variation among coho individuals. These differences likely reflect the different life histories and genetic heterogeneity of the salmon populations. Direct quantification of the density of host-specific parasite genotypes in water samples offers a management tool for predicting host population-level impacts.

The knowledge loop, a knowledge management tool for academic teaching

2008 ◽  
Author(s):  
Elfriede M. Ederer-Fick ◽  
Anita Giener ◽  
Helga Kittl-Satran ◽  
Brigitte Schachner
Keyword(s):  
Knowledge Management ◽  
Management Tool ◽  
Academic Teaching

Discussion on “Work study as a management tool”

1962 ◽  
Vol 41 (6) ◽  
pp. 334
Author(s):  
R. Young ◽  
Hurndall ◽  
E.H. Dallas ◽  
A. Kruger ◽  
H.W. Von Hooff ◽  
...  
Keyword(s):  
Management Tool ◽  
Work Study

Implementation of an institutional OPCAB-program using a specific quality management tool

2006 ◽  
Vol 54 (S 1) ◽  
Author(s):  
JC Saavedra Blume ◽  
M Zacher ◽  
SJ Klügl ◽  
A Diegeler
Keyword(s):  
Quality Management ◽  
Management Tool

Balanced Scorecard in the strategic planning of a construction company

2018 ◽  
Vol 1 (1) ◽  
pp. 1
Author(s):  
Roberth Frias ◽  
Maria Medina
Keyword(s):  
Strategic Planning ◽  
Strategic Management ◽  
Balanced Scorecard ◽  
Organization Theory ◽  
Management Control ◽  
Management Tool ◽  
The Balanced Scorecard ◽  
Construction Company ◽  
Construction Companies ◽  
The Impact

This research focused on the strategic management tool Balanced Scorecard and strategic planning, as a guide to guide the management of companies, allowing communication and the functionality of the strategy using KPIs that allow to identify, maintain control and increase efficiency and the achievement of optimal results. For the deductive hypothetical analysis, the specific factors that affect business management performance were grouped into two variables: Balanced Scorecard and Strategic Planning. The objective of the work was to demonstrate the impact of the Balanced Scorecard in the strategic planning of a construction company. In order to support the research, the following theories were approached: the Financial Theory, the Economic Theory of the Company, the Transaction Costs, the Network Theory, the Organization Theory, the Dependence on Resources, the Strategic Management Theory and the Business Diagnosis Theory. The result obtained confirms the hypothesis that there is a significant incidence of the Balanced Scorecard in the strategic planning of construction companies. In conclusion, the construction company has obtained significant improvements in the results in each of the indicators evaluated with the implementation of the Balanced Scorecard, demonstrating improvements in their management results, affirming that there is better performance and management control allowing them to achieve the organizational objectives set.

Predicting bycatch hotspots based on suitable habitat derived from fishery-independent data

2020 ◽  
Vol 641 ◽  
pp. 159-175
Author(s):  
J Runnebaum ◽  
KR Tanaka ◽  
L Guan ◽  
J Cao ◽  
L O’Brien ◽  
...  
Keyword(s):  
Habitat Suitability ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Gulf Of Maine ◽  
Homarus Americanus ◽  
Management Tool ◽  
American Lobster ◽  
Suitable Habitat ◽  
Climate Conditions ◽  
Suitability Index

Bycatch remains a global problem in managing sustainable fisheries. A critical aspect of management is understanding the timing and spatial extent of bycatch. Fisheries management often relies on observed bycatch data, which are not always available due to a lack of reporting or observer coverage. Alternatively, analyzing the overlap in suitable habitat for the target and non-target species can provide a spatial management tool to understand where bycatch interactions are likely to occur. Potential bycatch hotspots based on suitable habitat were predicted for cusk Brosme brosme incidentally caught in the Gulf of Maine American lobster Homarus americanus fishery. Data from multiple fisheries-independent surveys were combined in a delta-generalized linear mixed model to generate spatially explicit density estimates for use in an independent habitat suitability index. The habitat suitability indices for American lobster and cusk were then compared to predict potential bycatch hotspot locations. Suitable habitat for American lobster has increased between 1980 and 2013 while suitable habitat for cusk decreased throughout most of the Gulf of Maine, except for Georges Basin and the Great South Channel. The proportion of overlap in suitable habitat varied interannually but decreased slightly in the spring and remained relatively stable in the fall over the time series. As Gulf of Maine temperatures continue to increase, the interactions between American lobster and cusk are predicted to decline as cusk habitat continues to constrict. This framework can contribute to fisheries managers’ understanding of changes in habitat overlap as climate conditions continue to change and alter where bycatch interactions could occur.

An evaluation of a strategic de-stocking regime for dairying to improve nitrogen efficiency and reduce nitrate leaching from dairy farms in nitrate-sensitive areas

2000 ◽  
pp. 105-110
Author(s):  
Cecile De Klein ◽  
Jim Paton ◽  
Stewart Ledgard
Keyword(s):  
New Zealand ◽  
Nitrate Leaching ◽  
Management Practice ◽  
Field Measurements ◽  
Dairy Farms ◽  
Nitrogen Efficiency ◽  
Management Tool ◽  
Pasture Production ◽  
Leaching Losses ◽  
Sensitive Areas

Strategic de-stocking in winter is a common management practice on dairy farms in Southland, New Zealand, to protect the soil against pugging damage. This paper examines whether this practice can also be used to reduce nitrate leaching losses. Model analyses and field measurements were used to estimate nitrate leaching losses and pasture production under two strategic de-stocking regimes: 3 months off-farm or 5 months on a feed pad with effluent collected and applied back to the land. The model analyses, based on the results of a long-term farmlet study under conventional grazing and on information for an average New Zealand farm, suggested that the 3- or 5-month de-stocking could reduce nitrate leaching losses by about 20% or 35-50%, respectively compared to a conventional grazing system. Field measurements on the Taieri Plain in Otago support these findings, although the results to date are confounded by drought conditions during the 1998 and 1999 seasons. The average nitrate concentration of the drainage water of a 5-month strategic de-stocking treatment was about 60% lower than under conventional grazing. Pasture production of the 5-month strategic de-stocking regime with effluent return was estimated based on data for apparent N efficiency of excreta patches versus uniformlyspread farm dairy effluent N. The results suggested that a strategic de-stocking regime could increase pasture production by about 2 to 8%. A cost/ benefit analysis of the 5-month de-stocking system using a feed pad, comparing additional capital and operational costs with additional income from a 5% increase in DM production, show a positive return on capital for an average New Zealand dairy farm. This suggests that a strategic destocking system has good potential as a management tool to reduce nitrate leaching losses in nitrate sensitive areas whilst being economically viable, particularly on farms where an effluent application system or a feed pad are already in place. Keywords: dairying, feed pads, nitrate leaching, nitrogen efficiency, productivity, strategic de-stocking

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