annotated bibliography of fisheries economics literature - Office of ...

Vaughan, Douglas S. and James R. Waters (1994). "Comparison of Weighted
Nonlinear Regressions on the Von Bertalanffy Growth Curve Using
Data with Unequal Numbers at Age." Draft report, National Marine
Fisheries Service, Beaufort Laboratory, 101 Pivers Island Road,
Beaufort, North Carolina.
When estimating parameters of the von Bertalanffy growth curve from
length-at-age data for marine fishes, often most length measurements are from
younger fish, with fewer measurements of older fish. Plots of observed and
predicted lengths or comparisons of the estimated parameter L " with maximum
lengths observed may suggest that poor estimates of L " were obtained. In this
study, growth in length of individual fish was simulated from a von
Bertalanffy growth curve with known parameters, with the number of fish
sampled at each age depending on the instantaneous mortality rate, Z. Methods
of weighted nonlinear regression, applied to simulated growth data, included:
(1) unweighted; or weighted by the inverse of (2) the numbers of fish measured
at each age (1/N i ), (3) the standard error of the mean length at each age
(1/SE i ), and (4) the estimated standard deviation in length at each age (1/Ã ).
Less accurate and precise estimates of L " and K were obtained with increasing
Z for all weighting methods; except for large K, when more accurate parameter
estimates were obtained with increasing Z. Weighting by 1/N i yielded more
precise estimates of the growth parameter than the other weighting methods.
In practice, the advice of looking for patterns in the residuals should be
followed before making the final choice among estimation methods.
Vaughan, Douglas S., Joseph E. Powers, and Gerald P. Scott (1990).
"Preliminary Production Model Analysis of the North Atlantic
Swordfish Resource." ICCAT Working Document, SCRS/90/, U.S.
Department of Commerce, National Oceanic and Atmospheric
Administration, National Marine Fisheries Service, Southeast
Fisheries Center, Beaufort Laboratory, Beaufort, North Carolina.
The status of the North Atlantic swordfish resource is considered using
production model analysis. Sensitivity of the production model fits to stock
hypotheses, model parameters, and equilibrium assumptions as well as error in
measures of effective effort are considered in the analysis. When the catch
and effort time series is of short duration compared to the life span of the
fish species (as with swordfish), simulation results suggest that traditional
production model fits to data representing non-equilibrium (transitional)
conditions in a fishery may give spurious results and can form a poor basis
for management decisions.
Vaughan, Douglas S., John V. Merriner, Charles S. Manooch III, and
Jennifer Potts (1995). "Assessment of Southeastern U.S. Atlantic
Wreckfish Stock for Fishing Years 1988-1994." Report for Snapper
Grouper Assessment Group, South Atlantic Fishery Management
Council, National Marine Fisheries Service, Southeast Fisheries
Science Center, Beaufort Laboratory, 101 Pivers Island Road,
Beaufort, North Carolina, January, 32 pp.
The material included in this report updates that provided in the
February 1994 report (Vaughan it al., 1994) to the South Atlantic Fishery
Management Council's (SAFMC) Snapper Grouper Assessment Group. Included are
the latest analysis of length at age data, a summary of landings and length
frequency data from the fishery for 1988 through 1994 fishing years,
application of separable virtual population analysis to two catch at age
matrices, and analysis of yield and spawning stock biomass per recruit.
Appendix A presents a sensitivity analysis of the VPA by including limited
data recently obtained from the eastern North Atlantic. Complete landings for
6 8 7