A multivariate stock–recruitment function for cohorts with sympatric subclasses: application to maternal effects in rockfish (genus Sebastes)

2009 ◽  
Vol 66 (4) ◽  
pp. 557-564 ◽  
Author(s):  
Yasmin Lucero
Keyword(s):  
Maternal Effects ◽  
California Current ◽  
Mortality Rates ◽  
Life History Strategies ◽  
Juvenile Salmon ◽  
Black Rockfish ◽  
Older Mothers ◽  
Stock Recruitment ◽  
Flexible Framework ◽  
Sebastes Melanops

I present a multivariate stock–recruitment function (MSRF) for calculating recruitment when a cohort comprises sympatric subclasses. Sympatric subclasses emerge when there are closely interacting subgroups occupying a very similar niche, but whose ecology dictates distinct mortality rates. Examples include multispecies complexes of juvenile rockfish ( Sebastes spp.) in the California current and juvenile salmon ( Oncorhynchus spp.) in streams following different life history strategies. I derive an MSRF and apply it to the ecology of larval and juvenile rockfish with maternal effects. In several species of rockfish, older mothers produce superior larvae. This is called a maternal effect. For these species, larval and juvenile cohorts comprise several sympatric subclasses, each with a distinct mortality rate related to the age of their mothers. I apply this model to data for black rockfish ( Sebastes melanops ) in California and Oregon and find the recruitment estimates based on data from a declining population may overestimate productivity of a recovering population if maternal effects are neglected. The MSRF proves to be a flexible framework for studying recruitment in the presence of sympatric subclasses.

Reconstructing habitat use by juvenile salmon sharks links upwelling to strandings in the California Current

2015 ◽  
Vol 525 ◽  
pp. 217-228 ◽  
Author(s):  
AB Carlisle ◽  
SY Litvin ◽  
EL Hazen ◽  
DJ Madigan ◽  
KJ Goldman ◽  
...  
Keyword(s):  
Habitat Use ◽  
California Current ◽  
Juvenile Salmon

Estimation of annual mortality rates caused by early mortality syndromes (EMS) and their impact on salmonid stock–recruit relationships

2006 ◽  
Vol 63 (9) ◽  
pp. 1968-1981 ◽  
Author(s):  
Catherine G.J Michielsens ◽  
Samu Mäntyniemi ◽  
Pekka J Vuorinen
Keyword(s):  
Atlantic Salmon ◽  
Probabilistic Approach ◽  
Mortality Rates ◽  
Early Mortality ◽  
Stock Recruitment ◽  
The Baltic ◽  
Meta Analyses ◽  
Annual Mortality ◽  
Mortality Estimates ◽  
Related Mortality

In this paper, we demonstrate how information from broodstocks can be combined with lab information on alevins to obtain annual stock-specific mortality estimates from early mortality syndromes (EMS) using a probabilistic approach, how a hierarchical model structure can be used to predict these mortality rates for related, partly sampled, or unsampled stocks, and why these estimates should be used to remove the effect of this mortality on stock–recruit estimates. The approach has been illustrated for Atlantic salmon (Salmo salar) stocks in the Baltic Sea affected by the M74 syndrome. Results indicate that data on the proportion of M74-affected females, commonly used to approximate M74 mortality, overestimate actual M74-related mortality because of a declining trend in mortality among offspring of these females. The stock-specific M74 mortality estimates are used to account for nonstationarity in the stock–recruitment relationship caused by this fluctuating mortality. Because hierarchical meta-analyses assume exchangeability, the effect of M74 mortality is removed before including these stocks within hierarchical stock–recruit analyses of Atlantic salmon stocks, which are commonly unaffected by M74 mortality. Failure to remove the effect of M74 mortality on the stock–recruit data results in underestimation of the stock's productivity and resilience to exploitation, especially in the case of stocks with steep stock–recruit curves.

Annual Summary of Vital Statistics—1993

PEDIATRICS ◽  
1994 ◽  
Vol 94 (6) ◽  
pp. 792-803 ◽  
Author(s):  
Myron E. Wegman
Keyword(s):  
Infant Mortality ◽  
Death Rate ◽  
The United States ◽  
Mortality Rates ◽  
Vital Statistics ◽  
Infant Mortality Rate ◽  
Chronic Obstructive ◽  
Percentage Increase ◽  
Birth Rates ◽  
Older Mothers

A new low in the infant mortality rate was reached again in 1993, at 828.8 deaths per 100 000 live births, a decline of 2% from 848.7 in 1992. Births, marriages, and divorces were all lower, both in number and rate. Deaths and the death rate, however, both increased and, more significantly, the age-adjusted death rate increased. A likely explanation is the occurrence of influenza epidemics in early and late 1993. The rate of natural increase declined 8%, to a level of 6.9 per 1000 population. Final figures on births for 1992 indicate that, for the first time in many years, birth rates to teen-agers declined, more among black mothers than white. Increase in birth rate among older mothers continued at a somewhat slower rate than recently; older mothers tended to be better educated than the general population in their age groups. Total fertility rates were higher among mothers of Hispanic origin than among non-Hispanic blacks who, in turn, had higher rates than non-Hispanic whites. Among Hispanics the highest rates were in those of Mexican origin. Unlike recent years, birth rates to unmarried mothers did not increase in 1992. Prenatal care coverage improved, with more mothers seeking care early and fewer receiving late or no care. Electronic and fetal monitoring was performed on more than three-quarters of all births and ultrasound on more than half. Life expectancy decreased slightly, in contrast to recent years. Among major causes of death, increases were recorded in 1993 for chronic obstructive pulmonary diseases, pneumonia and influenza, and HIV infection, the latter having the largest percentage increase. Internationally, infant mortality rates in most other industrialized countries declined further in 1992. Comparatively, as in 1991, 21 other countries had infant mortality rates lower than the United States.

The Ecology of Juvenile Salmon in the Northeast Pacific Ocean: Regional Comparisons

2007 ◽  
Keyword(s):  
Fish Assemblages ◽  
Pacific Salmon ◽  
California Current ◽  
Minor Component ◽  
Species Group ◽  
Juvenile Salmon ◽  
Species Assemblages ◽  
Coastal Species ◽  
Night And Day ◽  
Associated Species

Abstract.—We compared epipelagic fish assemblages associated with juvenile (ocean-age 0) Pacific salmon <em>Oncorhynchus </em>spp. from neritic waters of the California Current and Alaska Current regions in the spring–summer and summer–fall periods of 2000–2004. Catches originated from rope trawl surveys conducted between latitudes 37°N and 60°N and spanned more than 1,100 km in the coastal and inshore habitats of each region. Catch data were used from the epipelagic sampling of waters from near surface to depths of about 18 m, primarily over the continental shelf. Catch composition, frequency of occurrence, and density were evaluated between regions and habitats for day sampling. Diel (night and day) catch comparisons were also made at a few localities in each region. In day catches from both regions, a total of 1.69 million fish and squid representing 52 fish families and 118 fish species were sampled from 2,390 trawl hauls. Ninety-seven percent of the daytime catch was composed of 11 fish families and squid in coastal and inshore habitats of each region: clupeids dominated catches in the California Current (72% and 76% of catch, respectively), and salmonids dominated catches in the Alaska Current (46% and 62% of catch, respectively). Juveniles comprised 81–99% of salmon sampled in both coastal and inshore habitats of each region. Frequencies of occurrence were highest for juvenile salmon in both regions, but average densities were highest for Pacific herring <em>Clupea pallasii </em>and Pacific sardine <em>Sardinops sagax </em>in the California Current region. Cluster analyses revealed distinct geographic breakpoints in coastal species assemblages off central Vancouver Island and in inshore species assemblages in southeastern Alaska. Species were found to cluster into six groups from coastal localities and four groups from inshore localities. Indicator species analysis and nonmetric multidimensional scaling revealed that most species of juvenile salmonids were located in northern localities. Although juvenile salmon had the most uniform distribution of any species group, their densities relative to associated species were dramatically lower in the California Current, suggesting a higher degree of interactions between juvenile salmon and other species in this region. Diel comparisons in both regions indicated substantially higher catches at night, particularly of clupeids, osmerids, and gadids. Salmonids were a relatively minor component of the night catch in both regions due to dramatic diel shifts in community structure. Additional study of diel interactions of juvenile salmon and associated species is needed to quantify habitat utilization dynamics in marine ecosystems.

Feeding behaviour of the kelp clingfish Rimicola muscarum residing on the kelp Macrocystis integrifolia

1978 ◽  
Vol 56 (4) ◽  
pp. 711-712 ◽  
Author(s):  
William Roland
Keyword(s):  
Food Chain ◽  
Feeding Behaviour ◽  
Black Rockfish ◽  
Harpacticoid Copepods ◽  
Macrocystis Integrifolia ◽  
Sebastes Melanops

The feeding behaviour of the kelp clingfish Rimicola muscarum Meek and Pierson residing on the blades of the kelp Macrocystis integrifolia Bory was described. The fish seized small invertebrates, mainly harpacticoid copepods, which were closely associated with the kelp blades. A four-step food chain involving R. muscarum was qualitatively determined. Diatoms epiphytic on the kelp blades were grazed by harpacticoid copepods. These and other small invertebrates were captured by the clingfish, which in turn was eaten by the black rockfish, Sebastes melanops, and the shiner perch, Cymatogaster aggregata.

scholarly journals Examining the utility of bulk otolith δ13C to describe diet in wild-caught black rockfish Sebastes melanops

2015 ◽  
Vol 23 (3) ◽  
pp. 201-208 ◽  
Author(s):  
VR von Biela ◽  
SD Newsome ◽  
CE Zimmerman
Keyword(s):  
Black Rockfish ◽  
Sebastes Melanops

scholarly journals Effects of marine-derived nutrients on population dynamics of sockeye salmon (Oncorhynchus nerka)

2008 ◽  
Vol 65 (8) ◽  
pp. 1635-1648 ◽  
Author(s):  
Tadayasu Uchiyama ◽  
Bruce P. Finney ◽  
Milo D. Adkison
Keyword(s):  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Isotope Analysis ◽  
Juvenile Salmon ◽  
Juvenile Survival ◽  
Water Residence Time ◽  
Nitrogen Stable Isotope ◽  
Factors Affecting ◽  
Stock Recruitment ◽  
Marine Derived Nutrients

The effects of marine-derived nutrients (MDN) on the productivity of sockeye salmon ( Oncorhynchus nerka ) stocks in Alaska, USA, were examined through nitrogen stable isotope analysis of smolts and mathematical models of the sockeye stock–recruit relationship. Smolt δ15N was used to infer the degree to which smolts depend on MDN for their growth. We found that characteristics of sockeye nursery lakes and watersheds significantly affected the availability of MDN to juvenile sockeye. The magnitude of escapement and water residence time were the most important factors affecting the MDN availability to juvenile salmon. Analysis of stock–recruit models indicated that regional environmental fluctuations had a large effect on stock productivities. However, stock–recruitment data showed little evidence that increasing MDN input to nursery lakes increased stock productivities. Stock–recruitment data may be poorly suited to detection of the influence of MDN because of the multitude of factors that influence juvenile survival in the first several years of their life.

Sign in / Sign up

Export Citation Format

Share Document