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07. Example Models

A.D. Letaw edited this page Sep 7, 2017 · 1 revision

Examples

Table of Contents

Bristol Bay Red King Crab (BBRKC)

The Bristol Bay Red King Crab (BBRKC) example can be found in the directory gmacs/examples/bbrkc/TwoSex. This example can be run by simply using the command make from the terminal within that directory. Alternatively the model may be run by navigating to the directory and using the command gmacs from the command line.

Below we provide plots of the output of this example model that were produced using the purpose-built R package gmr.

Model fit

The BBRKC model is fit to three types of data: catch, abundance indices and size-composition.

Catch

The BBRKC catch is split up into two fleets (trawl and pot) by sex (female, male or an aggregate of the two) and these catches are either retained or discarded. A plot of the observed catches is given below (bars) along with the model fit to these catches (lines).

Survey biomass

The BBRKC model is fit to two different abundance indices: BSFRF and NMFS trawl.

Size composition

Length, weight, molting and growth

Size

Selectivity

Time

Natural mortality

Mature male biomass (MMB)

Recruitment

St. Matthew Island Blue King Crab (SMBKC)

The St. Matthew Island Blue King Crab (SMBKC) example can be found in the directory gmacs/examples/smbkc. This example can be run by simply using the command make from the terminal within that directory. Alternatively the model may be run by navigating to the directory and using the command gmacs from the command line.

Model fit

The SMBKC model is fit to three types of data: catch, abundance indices and size-composition.

Catch

The SMBKC catch is split up into three fleets (pot, trawl bycatch and fixed bycatch) and these catches are either retained or discarded. A plot of the observed catches is given below (bars) along with the model fit to these catches (lines).

Survey biomass

The SMBKC model is fit to two different abundance indices: ADFG and NMFS trawl.

Pribilof Island Red King Crab (PIRKC)

An example model for Gmacs is under development, based on the Pribilof Island Red King Crab Fishery. More to come.