The Relation of Lake Population Density to Size of Young Sockeye Salmon (Oncorhynchus nerka)

1944 ◽  
Vol 6c (3) ◽  
pp. 267-280 ◽  
Author(s):  
R. E. Foerster
Keyword(s):  
Population Density ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Inverse Correlation ◽  
Fish Populations ◽  
Production Level ◽  
Natural Conditions ◽  
Significant Inverse Correlation ◽  
Appreciable Increase

For Cultus lake, B.C., data concerning relative numbers of young sockeye inhabiting the lake each year were obtained from the count of seaward migrants. From samples of the latter the sizes of the migrants were determined. For all years, 1927–1937, a statistically significant inverse correlation of −0.815 existed between extent of lake population and size of migrants. Under natural conditions the lake's sockeye productivity seems limited, probably due to limited plankton crop, and the sockeye values obtained in each year are compared to a production level of 6,000–8,000 kg. Experiments in reducing predaceous fish populations indicate appreciable increase in sockeye production.

scholarly journals Inverse correlation between average monthly high temperatures and COVID-19-related death rates in different geographical areas.

2020 ◽  
Author(s):  
Francesca Benedetti ◽  
Maria Pachetti ◽  
Bruna Marini ◽  
Rudy Ippodrino ◽  
Robert C. Gallo ◽  
...  
Keyword(s):  
Los Angeles ◽  
Population Density ◽  
High Temperatures ◽  
Death Rate ◽  
Inverse Correlation ◽  
The United States ◽  
Western World ◽  
Significant Inverse Correlation ◽  
Death Rates ◽  
Wide Range

Abstract Background With the aim of providing a dynamic evaluation of the effects of basic environmental parameters on COVID-19-related death rate, we assessed the correlation between average monthly high temperatures and population density, with death/rate (monthly number of deaths/1M people) for the months of March (start of the analysis and beginning of local epidemic in most of the Western World, except in Italy where it started in February) and April 2020 (continuation of the epidemic). Different geographical areas of the Northern Hemisphere in the United States and in Europe were selected in order to provide a wide range among the different parameters. The death rates were gathered from an available dataset. As a further control, we also included latitude, as a proxy for temperature.Methods Utilizing a publicly available dataset, we retrieved data for the months of March and April 2020 for 25 areas in Europe and in the US. We computed the monthly number of deaths/1M people of confirmed COVID-19 cases and calculated the average monthly high temperatures and population density for all these areas. We determined the correlation between number of deaths/1M people and the average monthly high temperatures, the latitude and the population density. Results We divided our analysis in two parts: analysis of the correlation among the different variables in the month of March and subsequent analysis in the month of April. The differences were then evaluated. In the month of March there was no statistical correlation between average monthly high temperatures of the considered geographical areas and number of deaths/1M people. However, a statistically significant inverse correlation became significant in the month of April between average monthly high temperatures (p=0.0043) and latitude (p=0.0253) with number of deaths/1M people. We also observed a statistically significant correlation between population density and number of deaths/1M people both in the month of March (p=0.0297) and in the month of April (p=0.0116), when three areas extremely populated (NYC, Los Angeles and Washington DC) were included in the calculation. Once these three areas were removed, the correlation was not statistically significant (p=0.1695 in the month of March, and p=0.7076 in the month of April). Conclusions The number of COVID-19-related deaths/1M people was essentially the same during the month of March for all the geographical areas considered, indicating essentially that the infection was circulating quite uniformly except for Lombardy, Italy, where it started earlier. Lockdown measures were implemented between the end of March and beginning of April, except for Italy which started March 9th. We observed a strong, statistically significant inverse correlation between average monthly high temperatures with the number of deaths/1M people. We confirmed the data by analyzing the correlation with the latitude, which can be considered a proxy for high temperature. Previous studies indicated a negative effect of high climate temperatures on Sars-COV-2 spreading. Our data indicate that social distancing measure are more successful in the presence of higher average monthly temperatures in reducing COVID-19-related death rate, and a high level of population density seems to negatively impact the effect of lockdown measures.

The Sodium, Potassium, and Water Content of the Flesh of Sockeye Salmon (Oncorhynchus nerka) in Relation to Sexual Development and Starvation

1967 ◽  
Vol 24 (2) ◽  
pp. 243-248 ◽  
Author(s):  
N. Tomlinson ◽  
J. R. McBride ◽  
S. E. Geiger
Keyword(s):  
Skeletal Muscle ◽  
Water Content ◽  
Sexual Development ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Spawning Migration ◽  
Natural Conditions ◽  
Sodium Potassium

The influence of feeding on the changes that occur in the skeletal muscle content of sodium, potassium, and water in sockeye salmon (Oncorhynchus nerka) during sexual development and spawning has been investigated. Feeding has little, if any, effect on the changes. Thus it appears that the period of starvation these fish undergo during their spawning migration under natural conditions is not the major cause of the degeneration of their skeletal muscle, but rather that these changes are associated in some manner with the development of the gonads, presumably through the mediation of hormones.

Otolith mass as a predictor of age in kokanee salmon (Oncorhynchus nerka) from four Colorado reservoirs

2012 ◽  
Vol 69 (10) ◽  
pp. 1569-1575 ◽  
Author(s):  
Jesse M. Lepak ◽  
C. Nathan Cathcart ◽  
Mevin B. Hooten
Keyword(s):  
Machine Learning ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Age Determination ◽  
Fish Populations ◽  
Financial Resources ◽  
Machine Learning Technique ◽  
Kokanee Salmon ◽  
Extensive Training ◽  
Learning Technique

Estimating ages of individuals in fish populations is crucial for determining characteristics necessary to effectively manage sport fisheries. Currently, the most accepted approach for fish age determination is using thin sectioned otoliths for interpretation. This method is labor-intensive, requires extensive training, and subjectively determines age. Several studies have shown that otolith mass increases with age, yet use of otolith mass to determine fish age is relatively underutilized. However, determining fish age using otolith mass requires relatively little training, is relatively nonsubjective, and is faster compared with other aging techniques. We collected kokanee salmon (i.e., landlocked sockeye salmon, Oncorhynchus nerka ) in 2004 from four reservoirs and from 2000 to 2009 in one reservoir to evaluate the efficacy of using otolith mass to determine fish ages. We used a machine learning technique to predict kokanee salmon ages using otolith mass and various other covariates. Our findings suggest this method has potential to substantially reduce time and financial resources required to age fish. We conclude that using otolith mass to determine fish age may represent an efficient and accurate approach for some species.

Density and Distribution of Young Sockeye Salmon (Oncorhynchus nerka) throughout a Multibasin Lake System

1958 ◽  
Vol 15 (5) ◽  
pp. 961-982 ◽  
Author(s):  
W. E. Johnson
Keyword(s):  
Population Density ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Catch Per Unit Effort ◽  
Lake System ◽  
Unit Effort ◽  
Limited Dispersal ◽  
Discrete Populations

Estimates of density (based on catch per unit effort with tow nets) of fingerling sockeye salmon populations in a large (174 sq. mile) multibasin lake system were carried out during 1955, 1956 and 1957. Density and distribution of fingerling sockeye throughout the lake system are related to density and distribution of the spawning parent populations. Discrete populations associated with discrete basins point to a limited dispersal as a result of the multibasin nature of the lake system. In one example, higher population density appears to result in greater dispersal.

A Natural Epizootic of Infectious Hematopoietic Necrosis in Fry of Sockeye Salmon (Oncorhynchus nerka) at Chilko Lake, British Columbia

1976 ◽  
Vol 33 (7) ◽  
pp. 1564-1567 ◽  
Author(s):  
Ian V. Williams ◽  
Donald F. Amend
Keyword(s):  
British Columbia ◽  
Sockeye Salmon ◽  
Virus Disease ◽  
Oncorhynchus Nerka ◽  
Infectious Hematopoietic Necrosis Virus ◽  
Normal Range ◽  
Necrosis Virus ◽  
Natural Conditions ◽  
Salmon Fry ◽  
Infectious Hematopoietic Necrosis

The first confirmed epizootic of infectious hematopoietic necrosis virus disease under natural conditions is reported for sockeye salmon, Oncorhynchus nerka, in Chilko Lake, British Columbia. The outbreak occurred among fish of the 1972 brood during the spring of 1973. An estimated 825.6 million eggs were deposited in the Chilko River in 1972, and the production of 31.4 million fry that migrated into the lake in 1973 was significantly lower than the 55.1 million fry expected. The egg-to-fry survival of 3.8% was the lowest ever recorded at Chilko Lake (1949–73). The estimated fry-to-smolt survival of 57.1%, however, was well within the normal range for this lake. Apparently IHN severely reduced the survival of the 1972 brood of sockeye salmon fry at Chilko Lake, and all or nearly all of the reduction occurred during the egg-to-fry stage of the life cycle.

scholarly journals Inverse correlation between average monthly high temperatures and COVID-19-related death rates in different geographical areas.

2020 ◽  
Author(s):  
Francesca Benedetti ◽  
Maria Pachetti ◽  
Bruna Marini ◽  
Rudy Ippodrino ◽  
Robert C. Gallo ◽  
...  
Keyword(s):  
Los Angeles ◽  
Population Density ◽  
High Temperatures ◽  
Death Rate ◽  
Inverse Correlation ◽  
The United States ◽  
Western World ◽  
Significant Inverse Correlation ◽  
Death Rates ◽  
Wide Range

Abstract Background With the aim of providing a dynamic evaluation of the effects of basic environmental parameters on COVID-19-related death rate, we assessed the correlation between average monthly high temperatures and population density, with death/rate (monthly number of deaths/1M people) for the months of March (start of the analysis and beginning of local epidemic in most of the Western World, except in Italy where it started in February) and April 2020 (continuation of the epidemic). Different geographical areas of the Northern Hemisphere in the United States and in Europe were selected in order to provide a wide range among the different parameters. The death rates were gathered from an available dataset. As a further control, we also included latitude, as a proxy for temperature. Methods Utilizing a publicly available dataset, we retrieved data for the months of March and April 2020 for 25 areas in Europe and in the US. We computed the monthly number of deaths/1M people of confirmed COVID-19 cases and calculated the average monthly high temperatures and population density for all these areas. We determined the correlation between number of deaths/1M people and the average monthly high temperatures, the latitude and the population density. Results We divided our analysis in two parts: analysis of the correlation among the different variables in the month of March and subsequent analysis in the month of April. The differences were then evaluated). In the month of March there was no statistical correlation between average monthly high temperatures of the considered geographical areas and number of deaths/1M people. However, a statistically significant inverse correlation became significative in the month of April between average monthly high temperatures (p=0.0104) and latitude (p=0.0119) with number of deaths/1M people. We also observed a statistically significative correlation between population density and number of deaths/1M people only in the month of April, when three areas extremely populated (NYC, Los Angeles and Washington DC) were included in the calculation. Once these three areas were removed, the correlation was not statistically significant (p=0.682). Conclusions The number of COVID-19-related deaths/1M people was essentially the same during the month of March for all the geographical areas considered, indicating essentially that the infection was circulating quite uniformly except for Lombardy, Italy, where it started earlier. Lockdown measures were implemented between the end of March and beginning of April, except for Italy which started March 9 th . We observed a strong, statistically significant inverse correlation between average monthly high temperatures with the number of deaths/1M people. We confirmed the data by analyzing the correlation with the latitude, which can be considered a proxy for high temperature. Previous studies indicated a negative effect of high climate temperatures on Sars-COV-2 spreading. Our data indicate that social distancing measure are more successful in the presence of higher daily average temperatures in reducing COVID-19-related death rate, and a high level of population density seems to negatively impact the effect of lockdown measures.

High Levels of Plasma Protein C in Nephrotic Syndrome

1985 ◽  
Vol 53 (01) ◽  
pp. 005-007 ◽  
Author(s):  
I Pabinger-Fasching ◽  
K Lechner ◽  
H Niessner ◽  
P Schmidt ◽  
E Balzar ◽  
...  
Keyword(s):  
Nephrotic Syndrome ◽  
Plasma Protein ◽  
Protein C ◽  
Inverse Correlation ◽  
Elevated Plasma ◽  
Significant Inverse Correlation ◽  
At Iii ◽  
Thrombotic Tendency ◽  
Protein C Activity

SummaryIn patients with severe nephrotic syndrome determinations of plasma protein C : Ag levels (8 patients: 5 adults, 3 children) and protein C activity (3 out of 8 patients) revealed significantly elevated plasma protein C concentrations. Furthermore we observed a significant inverse correlation of protein C : Ag to AT III : Ag levels. No protein C : Ag could be detected in the urine of two patients studied. We conclude from our data, that changes of plasma protein C do not contribute to the high thrombotic tendency in nephrotic syndrome.

scholarly journals The Dependence of Renal 68Ga[Ga]-DOTATOC Uptake on Kidney Function and Its Relevance for Peptide Receptor Radionuclide Therapy with 177Lu[Lu]-DOTATOC

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1216
Author(s):  
Falk Gühne ◽  
Alexander Heinzig ◽  
Philipp Seifert ◽  
Robert Drescher ◽  
Martin Freesmeyer
Keyword(s):  
Kidney Function ◽  
Specific Binding ◽  
Correlation Coefficients ◽  
Inverse Correlation ◽  
Peptide Receptor Radionuclide Therapy ◽  
Tracer Uptake ◽  
Significant Inverse Correlation ◽  
Peptide Receptor ◽  
Pet Ct ◽  
Induced Changes

Background: In addition to its SSTR-specific binding in tumors and healthy tissues, DOTATOC analogues accumulate in kidney parenchyma. Renal tracer uptake might be a surrogate of kidney function or dysfunction. This study aimed to evaluate if kidney function can be estimated from 68Ga[Ga]-DOTATOC uptake in PET/CT and its impact on the nephrotoxicity of 177Lu[Lu]-DOTATOC PRRT. Methods: Two cohorts of patients (A: 128 diagnostic patients; B: 32 PRRT patients) were evaluated retrospectively. SUV values of the kidneys, physiologically SSTR-expressing organs and in background compartments were assessed. Kidney function was calculated as eGFR by CKD-EPI creatinine equation. Pearson’s correlation coefficients and treatment-induced changes of uptake and kidney function were assessed and compared. Results: Kidney function and renal DOTATOC uptake showed a significant inverse correlation (R2 = 0.037; p = 0.029). Evaluated models of PET/CT measurements were not able to predict kidney function sufficiently. The uptake of other organs did not depend on eGFR. While the renal uptake increased after PRRT (p < 0.001), the kidney function did not change significantly (p = 0.382). Neither low pre-therapeutic eGFR nor high pre-therapeutic kidney uptake were risk factors of PRRT-induced deterioration in kidney function. Conclusion: The relevance of kidney function for renal 68Ga[Ga]-DOTATOC uptake is limited. The nephrotoxicity of 177Lu[Lu]-DOTATOC PRRT might be low and cannot be reliably predicted by pre-therapeutic measurements.

Resumption of anadromy or straying? Origins of Sockeye Salmon Oncorhynchus nerka in the Elwha River

2021 ◽  
Author(s):  
Thomas P. Quinn ◽  
George R. Pess ◽  
Ben J.G. Sutherland ◽  
Samuel J. Brenkman ◽  
Ruth E. Withler ◽  
...  
Keyword(s):  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Elwha River
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