Marine Mortality Schedules of Pink Salmon of the Bella Coola River, Central British Columbia

1968 ◽  
Vol 25 (4) ◽  
pp. 757-794 ◽  
Author(s):  
Robert R. Parker
Keyword(s):  
Mortality Rate ◽  
Early Life ◽  
Pink Salmon ◽  
Mortality Rates ◽  
Early Mortality ◽  
Initial Population ◽  
Natural Mortality ◽  
Time Period ◽  
Marking Technique ◽  
Bella Coola

The hypothesis that natural mortality rates of pink salmon during early life are generally much larger than during the later period has been tested for 3 brood-years of the Bella Coola River stock using a two-stage marking technique. Average daily losses to the population during the first 40 days are estimated to vary between 2 and 4%, and for the later 410-day period between 0.4 and 0.8%. These rates produce losses amounting to between 59 and 77% of the initial population during the first 40 days. Of the population surviving at 40 days, further losses of between 78 and 95% occurred. The latter losses are considered to be maximum estimates because of bias introduced by catches of unknown magnitude. Thus, although the early mortality is exceeded by the later, the time period is approximately 10 times as long, and the intensity of the mortality rate is much higher during early sea life.

Estimation of Sea Mortality Rates for the 1960 Brood-Year Pink Salmon of Hook Nose Creek, British Columbia

1964 ◽  
Vol 21 (5) ◽  
pp. 1019-1034 ◽  
Author(s):  
Robert R. Parker
Keyword(s):  
British Columbia ◽  
Mortality Rate ◽  
Marine Environment ◽  
Pink Salmon ◽  
Mortality Rates ◽  
Natural Mortality ◽  
Two Stage ◽  
Fishing Season ◽  
Salmon Fry ◽  
Bella Coola

Seaward migrating pink salmon fry at Hook Nose Creek, British Columbia, were estimated to total 1,153,000 in 1961. Of these, 41.5% or 479,000, were marked by amputation of both ventral fins (BV). Following this marking 36,900 fingerling were captured in the marine environment and marked by removal of the adipose and right ventral fins (ARV). During the 1962 fishing season 1,160,645 adult pinks were examined and 7050 BV and 184 ARV marks recognized. For the Hook Nose Creek stock, survival at sea from natural causes is shown to approximate 22% and the rate of exploitation was 95%. This stock is shown to be more exposed to fishing than the Bella Coola stock, for which a rate of exploitation of 69–80% is estimated. Rate of exploitation for Dean Channel stocks is even lower. These differences are explained as due to times of entry and rates of travel through the fishery. The two-stage marking experiment failed to estimate the natural mortality rate of juvenile pinks during the initial 5 weeks of sea life because of this dissimilarity between rates of exploitation on the stocks in the area.

Estimation of Sea Mortality Rates for the 1961 Brood-Year Pink Salmon of the Bella Coola Area, British Columbia

1965 ◽  
Vol 22 (6) ◽  
pp. 1523-1554 ◽  
Author(s):  
Robert R. Parker
Keyword(s):  
British Columbia ◽  
Pink Salmon ◽  
Mortality Rates ◽  
Disproportionate Representation ◽  
Natural Mortality ◽  
Marine Waters ◽  
Two Stage ◽  
Short Period ◽  
Seaward Migration ◽  
Bella Coola

A two-stage marking experiment was designed to estimate natural mortality rates of pink salmon during their early (coastal) and later (oceanic) periods of sea life. Difficulty was encountered because of disproportionate representation of various stocks in the marked populations, the stocks being subject to dissimilar rates of exploitation. Several assumptions were made for which the error introduced could not be fully evaluated. Under these assumptions, the results indicate (approximate values) that 55.7 million fry, resulting from the 1961 Burke Channel–Bella Coola stocks brood year, entered the sea. Of these, 77% died during the initial 40-day period of life in the enclosed marine waters. The following stage, from the time of seaward migration to adult return, a period of about 410 days, 78% of the remaining population died. The adult return was subjected to a rate of exploitation of 0.85 which produced a catch of 2.5 million fish. The spawning escapement was approximately 450,000 fish. It is established that the rate of natural mortality during the initial short period was much more severe than that during the remaining period of sea life.

Contrasting decadal trends in mortality between large and small individuals in skate populations in Atlantic Canada

2013 ◽  
Vol 70 (1) ◽  
pp. 74-89 ◽  
Author(s):  
Douglas P. Swain ◽  
Ian D. Jonsen ◽  
James E. Simon ◽  
Trevor D. Davies
Keyword(s):  
State Space ◽  
Early Life ◽  
Mortality Rates ◽  
State Space Models ◽  
Natural Mortality ◽  
Juvenile Growth ◽  
Life Stages ◽  
Grey Seal ◽  
Early Life Stages ◽  
Scotian Shelf

Mature thorny (Amblyraja radiata), winter (Leucoraja ocellata), and smooth (Malacoraja senta) skates have declined to very low abundance in the southern Gulf of St. Lawrence (SGSL) and on the eastern Scotian Shelf (ESS). We used stage-structured state-space models to examine decadal patterns in mortality rates in these skates. Mortality at early life stages (embryos in egg cases, hatchlings, and (or) small juveniles) appeared to decrease between the 1970s and the 2000s. In contrast, estimated mortality rates increased for larger individuals over this period. Although potentially confounded in models with effects of any changes in juvenile growth, the estimated increases in mortality could not instead be attributed solely to changes in growth. Increases in the mortality of large individuals appeared to reflect increases in natural mortality, possibly due to predation by grey seals. Increases in natural mortality were not evident for skates on the neighbouring western Scotian Shelf, where grey seal abundance has remained lower. Even in the absence of fishing, recovery of skates is unlikely under current ecosystem conditions in the SGSL and on the ESS.

Estimations of Ocean Mortality Rates for Pacific Salmon (Oncorhynchus)

1962 ◽  
Vol 19 (4) ◽  
pp. 561-589 ◽  
Author(s):  
Robert R. Parker
Keyword(s):  
Mortality Rate ◽  
Sockeye Salmon ◽  
Pacific Salmon ◽  
Pink Salmon ◽  
Total Mortality ◽  
Mortality Rates ◽  
Mortality Factor ◽  
Sampling Errors ◽  
Instantaneous Rate ◽  
Factor C

A conceptual model representing natural marine mortality rates of Pacific salmon is developed. Ocean mortality rate (q) is taken as the base to which coastal mortality rates of juveniles (c) and of adults (k) are additive factors. The effect of marking is taken as a multiplicative factor (m) of the instantaneous rate (i) where i = q + c + k. Together with time these values are incorporated into the balanced equation[Formula: see text]where N0 denotes the population entering the sea and R1, R2, R3 denote the returns at succeeding times of maturity. The locus of c + k = f(q) is used to graphically depict all possible combinations of c + k and q within the limits [q, c + k = 0]. Intersections of loci are taken as estimates of values of q and c + k which satisfy two sets of data. Available data for sockeye salmon (O. nerka) from Cultus Lake, Chilko Lake and Hooknose Creek, British Columbia, Karluk River and Bare Lake, Alaska, and Dalnee River, Kamchatka, pink salmon (O. gorbuscha) and chum salmon (O. keta) from Hooknose Creek, chinook salmon (O. tshawytscha) from the coast of Southeast Alaska and coho (O. kisutch) from the Eel River, California, are utilized. It is concluded that ocean mortality is relatively constant, of the order of magnitude q = 0. 32 or S = 73% annually. A juvenile coastal mortality factor (c) apparently exists and is characteristic of the species and race through the media of size of migrants, time spent in the costal area, and geography. An adult coastal factor (k) may exist but is of negligible influence on the total mortality rate. While the data utilized collectively may be considered as extensive, serious defects in sampling errors and undefined variability were encountered. It is doubted that mortality rates can be more accurately defined from any repetition of experiments used, hence a more direct approach is indicated for solution of this problem.

scholarly journals Impact of stroke unit in a public hospital on length of hospitalization and rate of early mortality of ischemic stroke patients

2013 ◽  
Vol 71 (10) ◽  
pp. 774-779 ◽  
Author(s):  
Maria Sheila G. Rocha ◽  
Ana Claudia F. Almeida ◽  
Osorio Abath Neto ◽  
Marianna P. R. Porto ◽  
Sonia Maria D. Brucki
Keyword(s):  
Mortality Rate ◽  
Stroke Unit ◽  
Public Hospital ◽  
Unit Group ◽  
Mortality Rates ◽  
General Ward ◽  
Early Mortality ◽  
Stroke Patients ◽  
Length Of Hospitalization ◽  
Overall Mortality

We ascertained whether a public health stroke unit reduces the length of hospitalization, the rate of inpatient fatality, and the mortality rate 30 days after the stroke. Methods We compared a cohort of stroke patients managed on a general neurology/medical ward with a similar cohort of stroke patients managed in a str oke unit. The in-patient fatality rates and 30-day mortality rates were analyzed. Results 729 patients were managed in the general ward and 344 were treated at a comprehensive stroke unit. The in-patient fatality rates were 14.7% for the general ward group and 6.9% for the stroke unit group (p<0.001). The overall mortality rate 30 days after stroke was 20.9% for general ward patients and 14.2% for stroke unit patients (p=0.005). Conclusions We observed reduced in-patient fatalities and 30-day mortality rates in patients managed in the stroke unit. There was no impact on the length of hospitalization.

Trends in the drowning mortality rate in Iran

2019 ◽  
Vol 26 (4) ◽  
pp. 351-359
Author(s):  
Pegah Derakhshan ◽  
Sahar Saeedi Moghaddam ◽  
Soheil Saadat ◽  
Ali Ghanbari ◽  
Nazila Rezaei ◽  
...  
Keyword(s):  
Mortality Rate ◽  
Age Groups ◽  
Mortality Rates ◽  
Global Burden ◽  
Data Set ◽  
Time Period ◽  
Males And Females ◽  
Disease Study ◽  
Death By Drowning ◽  
Burden Of Diseases

ObjectiveThe WHO estimates the global incidence of death by drowning to be about 300 000 cases per year. The objective of this study was to estimate the trend in mortality due to drowning in all provinces of Iran in all age groups and both genders from 1990 to 2015.Study designThe National and Subnational Burden of Diseases (NASBOD) project is a comprehensive project in Iran. It is based on the Global Burden of Disease study and includes novel methods to estimate the burden of diseases in Iran.MethodsThis study used the results of the mortality rate due to drowning as part of NASBOD and investigated the causes behind the mortality rates. The data set recorded mortality rates by 19 age groups and two genders with the corresponding subnational pattern during the time period from 1990 to 2015.ResultsThe drowning mortality rate decreased in Iran from 1990 to 2015. From 1990 to 2015, the annual percentage change for males and females was −5.28% and −10.73%, respectively. There were 56 184 male and 21 589 female fatalities during the study period. The highest number of deaths was seen in 1993 with 4459, and the lowest number of fatalities was observed in 2015 with 903 deaths.ConclusionOur data showed a decline in drowning mortality in Iran from 1990 to 2015, but the rates and declines varied by province. Our findings are of great importance to health officials and authorities in order to further reduce the burden of drowning.

scholarly journals Growth, maturation, and longevity of maturation cohorts of Norwegian spring-spawning herring

2004 ◽  
Vol 61 (2) ◽  
pp. 165-175 ◽  
Author(s):  
Raymond J.H. Beverton ◽  
Arvid Hylen ◽  
Ole-Johan Østvedt ◽  
John Alvsvaag ◽  
Terence C. Iles
Keyword(s):  
Mortality Rate ◽  
Small Proportion ◽  
Stock Assessment ◽  
Adult Life ◽  
Total Mortality ◽  
Mortality Rates ◽  
Natural Mortality ◽  
Marine Research ◽  
First Time ◽  
Age At Maturation

Abstract In 1907, the Bergen Institute of Marine Research started regular sampling of scales and lengths from landings of mature Norwegian spring-spawning herring. The actual age of each fish when caught was recorded, and from the early 1920s also the age at which it spawned for the first time. The present analyses concern biological samples secured during the fishing seasons 1940–1964. Herring in this stock do not all reach maturity at the same age. A small proportion of any one year class matures at 3 years. The majority matures from the age of 4–7 years, and a small proportion of some year classes at 8 and even 9 years of age. Subsequent age composition and growth of each maturation cohort were followed throughout mature life after spawning for the first time. The maximum age was found to increase with age at maturation, rising to an asymptote of about 22 years. The von Bertalanffy parameter L∞ shows an increasing trend with age at maturation, while K decreases. There is no strict length threshold at maturation and the curve joining the length at which each maturation cohort reaches maturity is less steep than the growth curve itself over the range of maturation ages. The data suggest that fish in this stock spawn, on average, eight times during a period of their life history in which the mortality rate is independent of age. After these eight spawnings, at an age referred to in this paper as the hinge age, the mortality rate increases sharply. Thus, the adult life is divided into two phases, called here pre-senescent and senescent. The total mortality rates in the pre-senescent phase are relatively stable for all maturation cohorts 3–9, but there is some evidence of a trend towards higher mortality rates during the senescent phase for the youngest maturing fish. This trend is caused mainly by a reduced natural mortality in the fish that mature when older. These findings have interesting demographic implications. Additional mortality due to fishing will change the relative contribution of young and old maturation cohorts in the senescent phase, thus making it appear that natural mortality is dependent on the intensity of fishing. Consequently, for stock assessment, analysis on a cohort basis seems advisable.

Immune-mediated hemolytic anemia: 70 cases (1988-1996)

1999 ◽  
Vol 35 (5) ◽  
pp. 384-391 ◽  
Author(s):  
ME Reimer ◽  
GC Troy ◽  
LD Warnick
Keyword(s):  
Treatment Group ◽  
Mortality Rate ◽  
Hemolytic Anemia ◽  
Median Survival ◽  
Mortality Rates ◽  
Survival Times ◽  
Treatment Regimens ◽  
Time Period ◽  
Immune Mediated ◽  
Overall Mortality

Survival times and mortality rates in dogs with idiopathic immune-mediated hemolytic anemia (IMHA) have been infrequently reported in the literature. This study evaluates survival and mortality in a large group of dogs with IMHA. The association of age, sex, and breed with IMHA was evaluated by comparing affected dogs to control dogs admitted to the hospital during the same time period. Treatment regimens were reviewed to determine the effects of different agents upon survival of dogs with IMHA during hospitalization and after discharge. Median survival times for each treatment group were 57 days (prednisone), 28 days (prednisone, cyclophosphamide), 974 days (prednisone, azathioprine), 15 days (prednisone, cyclophosphamide, azathioprine), and one day (no treatment). Overall mortality rate in the population of dogs studied was 70%. Twenty-nine (41.4%) dogs either died or were euthanized while hospitalized. Forty-one (59%) dogs were discharged from the hospital. Of the dogs discharged, 10 died within the first month, another five died within three months, and another five died within a year of discharge due to assumed complications of therapy or relapses of IMHA.

scholarly journals The Addition of Rituximab to Chemotherapy Decreased Rates of Primary Surgery for Gastric Diffuse Large B-Cell Lymphoma without Increasing Early Mortality

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4475-4475
Author(s):  
Eric Wiedower ◽  
Smith Giri ◽  
Andrew Fintel ◽  
Philip Prouet ◽  
Elena Paulus ◽  
...  
Keyword(s):  
Mortality Rate ◽  
B Cell ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Mortality Rates ◽  
Early Mortality ◽  
P Value ◽  
Stage At Diagnosis ◽  
Large B Cell Lymphoma ◽  
Large B Cell

Abstract Introduction: Rituximab (R) has improved outcomes in diffuse large B-cell lymphoma (DLBCL) but early complications, such as gastric perforation, have been reported (median time to event 6 days). As the role of surgery for gastric diffuse large B cell lymphoma (gDLBCL) has evolved from the primary management of the disease to the management of its complications, we sought to further define surgical trends and to explore whether the introduction of R and the decreasing rates of primary surgery influenced early mortality in patients with gDLBCL. Methods: The authors utilized the Surveillance Epidemiology and End Results (SEER) 18 database (November 2014 submission) to extract relevant data on patients with gDLBCL diagnosed between 1983-2012 using the case listing session. Eligible cases of gDLBCL were identified from the SEER 13 database using a combination of International Classifications of Diseases for Oncology, 3rd edition (ICD-O-3) code for DLBCL (9680/3) and site codes for stomach (C60.x). Primary site-specific cancer directed surgery using SEER site-specific surgical codes and annual trends in the receipt of surgery among patients with gDLBCL using Joinpoint regression program were evaluated. Unadjusted percentages along with 95% confidence intervals (computed using Bootstrapping methods) were computed for each year. Changes in the trend of surgical rates were evaluated by Monte Carlo Permutation method. We compared the impact of the introduction of R on early mortality rates in our study population. Using the year 2006, date of FDA approval for R as first-line therapy, as a cutoff, we studied the 30 and 60-day mortality rates. Multivariate logistic regression was used to study the impact of year of diagnosis (before and after 2006) on early mortality rates adjusting for age, sex, race and stage at diagnosis. The level of significance chosen was 0.05. All p-values were two sided. Results: 5814 patients (pts) with gDLBCL were identified. There were 4124 pts diagnosed prior to 2006 and 1690 patients with gDLBCL diagnosed after 2006. Median age was 71 years (range 1 to 105 years), of which 55.5% (n=3224) were males and 80.7% (n=4694) were white. The majority of patients were Stage I (43.7%; n =2539) or Stage II (19.7%; n= 1145) at diagnosis. 16% (n=932) received any form of radiation therapy. 1088 (18.7%) received primary cancer directed surgery. Patients receiving surgery for gDLBCL declined from 63% in 1983 (34 out of 54 patients) to 8% (19 out of 250) in 2012. Joinpoint trend analysis revealed that the sharpest decline was seen between the years 2000-2010 (annual percentage change, APC -12.31; 95% confidence interval -16.8 to -7.6; p value <0.01). The adjusted rates of surgery computed using poisson regression (adjusted for age, sex, race and stage at diagnosis) declined from 54.4% in 1983 to 6.9% in 2012 with an APC of -8.9% (95% CI -9.7% to -8.3%; p value <0.01). The 30-day mortality rate prior to 2006 was 9.7% as compared to 10.3% among patients diagnosed after 2006 (p value 0.48). The 60-day mortality rate was similar in the two groups as well (16.3% versus 15.2%; p value 0.29). Multivariate logistic regression showed that the patients before and after 2006 were similar in terms of the 30-day mortality rate (OR 0.97; 95% CI 0.79-1.18; p value 0.79) and the 60-day mortality rate (OR 0.94; 95% CI 0.80-1.11; p value 0.48) after adjusting for age, gender, race and stage at diagnosis. Conclusions: The period after the introduction of R was associated with the sharpest decline in primary cancer directed surgery for gDLBCL. While R is associated with perforation risk, no significant increase in 30 or 60-day mortality was seen in those treated after R was approved for first-line therapy. While R appears to have significantly changed how surgery is utilized in gastric DLBCL, early mortality was unchanged. Figure 1. Trend of surgical rates Figure 1. Trend of surgical rates Disclosures No relevant conflicts of interest to declare.

Trends In Mortality Rates and Age of Death In Sickle Cell Disease (SCD): 1979–2005

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 736-736
Author(s):  
Sophie Lanzkron ◽  
Carlton Haywood
Keyword(s):  
Sickle Cell Disease ◽  
Mortality Rate ◽  
Cause Of Death ◽  
Sickle Cell ◽  
Mortality Rates ◽  
Age At Death ◽  
Cell Disease ◽  
Time Period ◽  
The Mean ◽  
Age Of Death

Abstract Abstract 736 While improvements in care have resulted in significant decreases in mortality for children with SCD, it is unclear if similar decreases in mortality rates have occurred in adults with the disease. The purpose of this research is to describe mortality rates and trends in age of death for those with SCD over the last 3 decades. We used the National Center for Health Statistics Multiple Cause of Death (MCOD) files to examine age at death and calculate mortality rates from 1979–2005. ICD9 and ICD10 codes for SCD were used as appropriate to identify sickle cell related deaths. Mortality rates were calculated as deaths per 100,000 African American population. The number of African Americans each year was determined using available census data. Trends in mortality rates were examined using negative binomial regression and age of death was examined using t-tests and linear regression. After excluding certificates with codes for sickle trait and those with multiple sickle codes we identified 16,654 sickle-related deaths. The age range was 0 to 107 years. Mean age of death was significantly different for men (33.4, 95% CI [33.0, 33.7]) and women (36.9, 95% CI [36.5, 37.4]). SCD was the most common listed underlying cause of death (COD) at 62.8%. Infection was the second most common COD (5.9%). Controlling for sex and the presence of infection as COD, the mean age of death increased significantly by 0.08 years (p<0.001) each year over the time period studied, with men on average dying 4.3 years earlier than women (p<0.001). The mean age of death in 2005 was 43 yrs for women and 37 yrs for men. Those with COD of pulmonary hypertension, stroke and renal disease had a significantly older age of death than those without those diagnoses, while having infection as the underlying COD was associated with a younger age at death. The overall mortality rate increased by 0.7% (p<0.001) each year over the time period studied. Mortality rates for adults and children over time are shown in Figure 1. The adult (>19 yrs) mortality rate increased by 1% (p<0.001) each year over the time period studied. The pediatric mortality rate decreased by 3% (p<0.001) each year over the time period studied. When controlling for the pediatric mortality rate the adult mortality rate increased by 1.6% (p<0.001) each year. This data confirms prior studies showing a significant decrease in mortality for children with sickle cell disease over the last 30 yrs. The mortality rate for the adult population appears to be steadily increasing over the same time period. It seems unlikely that this is due merely to an influx of younger patients surviving to adulthood. Further investigation as to the cause of the increasing mortality rate in adults is needed. Disclosures: No relevant conflicts of interest to declare.

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