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Full-Text Articles in Aquaculture and Fisheries
Simulations Of The Effect Of Sample Size On The Maximum Observed Age In A Fish Population, John M. Hoenig
Simulations Of The Effect Of Sample Size On The Maximum Observed Age In A Fish Population, John M. Hoenig
Reports
No abstract provided.
Simulations To Compare The Performance Of Two Length-Based Estimators Of Total Mortality Rate, Amy Y. Then, John M. Hoenig
Simulations To Compare The Performance Of Two Length-Based Estimators Of Total Mortality Rate, Amy Y. Then, John M. Hoenig
Reports
Mean length-based methods to estimate instantaneous total mortality rates, Z, are important assessment tools for data-poor stocks. One commonly used method was developed by Beverton and Holt (1956). The behavior of this method, especially in relation to bias, has been fairly well characterized. Another method by Ehrhardt and Ault (1992) was proposed to "correct" the Beverton-Holt (BH) method for applications to length frequency distributions that are truncated at the upper end. The Ehrhardt-Ault (EA) method has zero bias at equilibrium when there is no variability in length at age but the reliability of the method has not been demonstrated under …
Supplementary Data And Analysis For Estimating Walleye Selectivity, Matthew W. Smith, John M. Hoenig, Neil Kmiecik, Mark A. Luehring, Melissa T. Drake, Patrick J. Schmalz, Greg G. Sass
Supplementary Data And Analysis For Estimating Walleye Selectivity, Matthew W. Smith, John M. Hoenig, Neil Kmiecik, Mark A. Luehring, Melissa T. Drake, Patrick J. Schmalz, Greg G. Sass
Reports
This document has been issued as VIMS Data Report 61 and provides data tables and results of exploratory analyses conducted as part of the complete data analysis for Myers et al. 2014 published in the Transactions of the American Fisheries Society. Estimates of size- and sex-specific selectivity of fishing gear are important for making informed management decisions. We distinguish between capture selectivity – the relative catchability of the components of the population – and harvest selectivity, which is the combined effects of capture selectivity and the decision to retain or release a fish of a given population component. We used …
Results Of Evaluating The Performance Of Empirical Estimators Of Natural Mortality Rate, Amy Y. Then, John M. Hoenig
Results Of Evaluating The Performance Of Empirical Estimators Of Natural Mortality Rate, Amy Y. Then, John M. Hoenig
Reports
Natural mortality rate, M, of fish is a highly influential stock assessment parameter. The M parameter is also difficult to estimate directly and reliably. Various empirical estimators have been developed to estimate M indirectly, based on relationships established between M and predictor variables such as growth parameters, lifespan and water temperature (e.g., Beverton and Holt, 1959; Alverson and Carney, 1975; Pauly, 1980; Hoenig, 1983). Despite the importance of these estimators, there is no consensus in the literature on how well they work in terms of prediction error or how their performance may be ranked. Then et al. (2015) evaluated estimators …
Simulated Performance Of Catch Curve Methods For Estimating Total Mortality Rate, Matthew W. Smith, John M. Hoenig
Simulated Performance Of Catch Curve Methods For Estimating Total Mortality Rate, Matthew W. Smith, John M. Hoenig
Reports
This document has been issued as VIMS Data Report 60 and provides additional simulation results for Smith et al. (2012) published in the North American Journal of Fisheries Management. Catch curve methods are a basic tool of population dynamics for estimating total mortality rate from age composition. There are a number of methodological issues which remain unresolved. Smith et al. (2012) attempts to provide guidelines on the use of these methods based on extensive Monte Carlo simulations. This report presents additional simulation results to supplement the results in the journal article. The estimators, evaluation criteria, simulation procedures, and conditions simulated …
Juvenile Finfish And Blue Crab Stock Assessment Program Bottom Trawl Survey Annual Data Report Series, Volume 1991, Christopher F. Bonzek, Patrick J. Geer, James A. Colvocoresses, Robert E. Harris
Juvenile Finfish And Blue Crab Stock Assessment Program Bottom Trawl Survey Annual Data Report Series, Volume 1991, Christopher F. Bonzek, Patrick J. Geer, James A. Colvocoresses, Robert E. Harris
Reports
This report presents a summary page for each tow conducted by the Virginia Institute of Marine Science, Juvenile Fish and Blue Crab Trawl Survey during 1991. The sampling methods and summarized data are presented in Bonzek et al. (1992). Data analysis and calculations of juvenile indices for selected species are presented in Colvocoresses et al. (1991). The purpose of this report is simply to provide a "hard copy" record of trawl results. It also provides a method to retrieve information about one or several particular trawls without consulting computerized archives. · · All data about each tow are presented, except …
A Comparative Study Of Dry Weight Measurements Of Oyster Soft Tissue, Cheol Mo, Bruce Neilson
A Comparative Study Of Dry Weight Measurements Of Oyster Soft Tissue, Cheol Mo, Bruce Neilson
Reports
Four alternative drying methods for oyster soft tissue were compared: oven drying at 105, 100 and 80°C and freeze drying. Weights were recorded every 12 hours for 5 days, and after sample treatments were switched, every 24 hours for another 3 days. The time required for all of the oysters in a treatment to reach constant weight were 36, 36, 60, and 120 hours for the 105, 100, 80°C ovens and freeze drier respectively. Within a treatment, the time for an individual oyster to reach constant weight was not related to that weight. For oven drying, drying was rapid and …
Procedure For Creating Digital Baylor Coverages In Arc/Info, Gary F. Anderson, J. Berchman Smithson, Anna K. Kenne
Procedure For Creating Digital Baylor Coverages In Arc/Info, Gary F. Anderson, J. Berchman Smithson, Anna K. Kenne
Reports
Baylor Grounds were defined by a survey of the natural oyster beds in Virginia conducted by Lt. J.B. Baylor, USN, and completed in 1894. The original purpose of the survey was to set aside naturally productive oyster beds for protection from private leasing, which was a controversial concept at the time. Hence the commonly used term 'Baylor Grounds' is synonymous with Virginia's public oystering grounds in the present day. Other surveys, conducted later, have added to the original Baylor acreage, resulting in an estimated 243, 000 acres of public oyster grounds in Virginia. For further information on the oyster industry …
Zinc Distributions In Sediments, The Common Mussel, Mytilus Edulis (L.), The American Oyster, Crassostrea Virginica (Gmelin), And The Commensal Pea Crab, Pinnotheres Ostreum (Say), Cheol Mo, Bruce Neilson
Zinc Distributions In Sediments, The Common Mussel, Mytilus Edulis (L.), The American Oyster, Crassostrea Virginica (Gmelin), And The Commensal Pea Crab, Pinnotheres Ostreum (Say), Cheol Mo, Bruce Neilson
Reports
Oysters and mussels of varying sizes and sediment samples were collected from oyster beds with different salinity regimes of three Virginian coastal plain rivers: Rappahannock River. James River. and Piankatank River. Zinc concentrations of 1) soft tissues. gut contents. and shells of the oysters. 2) soft tissues of the mussels. 3) pea crabs. and 4) sediment samples were measured with a flame atomic absorption (Flame AA) spectrophotometer. Particulate organic carbon and nitrogen concentrations ·of the sediments were measured with a carbon-nitrogen analyzer. The contribution of extraneous materials. such as gut contents. faeces. and pea crabs. to the variability in oyster …
Experimental Studies Of Zinc-65 Uptake Rates By The American Oyster, Crassostrea Virginica With Regard To Salinity, Sediment Concentration, And Body Size, Cheol Mo, Bruce Neilson
Experimental Studies Of Zinc-65 Uptake Rates By The American Oyster, Crassostrea Virginica With Regard To Salinity, Sediment Concentration, And Body Size, Cheol Mo, Bruce Neilson
Reports
Three sets of twelve oysters from the ,James River were placed in three recirculating aquaria dosed with the radioactive tracer zinc-65. All aquaria had the same amount of river bottom sediment which was kept in suspension by the water movement caused by aeration; one aquarium had twice as much tracer as the other two. The salinity of one of the low dose aquaria and. the high dose aquarium was maintained at 18 0/00: the other low dose aquarium was maintained at 1:2 0/00. All other factors were kept constant. Sediment-water-tracer mix was added to the aquaria every 12 hours. Water …
The Vims Trawl Survey : Juvenile Atlantic Croaker, Brenda L. Norcross, Ginny H. Shaw
The Vims Trawl Survey : Juvenile Atlantic Croaker, Brenda L. Norcross, Ginny H. Shaw
Reports
An index of juvenile croaker recruitment was developed to test proposed relationships between juveniles and environmental factors. The VIMS trawl survey data base is unique on the east coast because of its duration and continuity. No other data set exists that samples the same species in the same locality with concurrent physical data over a long period of time.
Relationship Between The Chesapeake Bay Blue Crab And Its Climatological Environment : Oceanographic And Atmospheric Data, Robert E. Harris Jr., Willard A. Van Engel
Relationship Between The Chesapeake Bay Blue Crab And Its Climatological Environment : Oceanographic And Atmospheric Data, Robert E. Harris Jr., Willard A. Van Engel
Reports
Monthly and annual means of 38 oceanographic and atmospheric variables, for the calendar years 1958 through 1975, are presented in tables.
Perkinsus Marinus = Dermocystidium Marinum ("Dermo") In Virginia, 1950-1980 : A Record Of Fluid Thioglycollate Tests For Dermo In Oysters From Public And Private Oyster Beds, And From Trays Of Disease-Free Oysters Transplanted To Areas Where Msx And Dermo Are Endemic, Jay D. Andrews
Reports
No abstract provided.
License Records Of The Blue Crab Fisheries, Virginia And Maryland, 1898-1960, Willard A. Van Engel, Frank J. Wojcik
License Records Of The Blue Crab Fisheries, Virginia And Maryland, 1898-1960, Willard A. Van Engel, Frank J. Wojcik
Reports
Gear used in the Virginia and Maryland blue crab fisheries have been regulated since 1989. Numbers of fishermen and kinds of fishing devices have been reported in official state publications, in Virginia from 1899 through 1941 and in Maryland from 1916 to date. Unfortunately, these reports have sometimes been incomplete. The fact that Virginia licenses have been reported by fiscal year and Maryland's by calendar year, has made analysis and comparison difficult. The most complete Virginia record was extracted from files of the Commission of Fisheries, and is made available here for the first time, for the calendar years 1920 …
Catch And Value Of Various American Crustaceans 1929-1960, Willard A. Van Engel, Frank J. Wojcik
Catch And Value Of Various American Crustaceans 1929-1960, Willard A. Van Engel, Frank J. Wojcik
Reports
Occasional reference has been made to the relative magnitude of the catch of the blue crab in waters outside Chesapeake Bay, yet comparisons are not easily made unless data are readily available. Both parallel and opposite trends in catch have been observed. These could be reflections of the amount of fishing effort or the size of the crab stocks. Comparable records of other crustacean fisheries are often of interest. Compilations are given here of data on crabs, shrimp and lobsters originally published in "Fishery Industries of the United States" and "Fishery Statistics of the United States".