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seacode / gmacs

A generic size-structured stock assessment model
https://seacode.github.io/gmacs
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Discrete Fisheries #72

Closed smartell closed 8 years ago

smartell commented 9 years ago

Issue

The current state of Gmacs assumes a continuous catch equation. Historically this was the case when fisheries operated year round. During the derby days the fishery was concentrated in time, and post rationalization, the fishing season is a bit more protracted.

Fix

Change the catch accounting and population model to accommodate multiple time steps with each year. Sequence of events may differ by crab species, and may differ over time due to changes in fisheries operations, season dates, fisheries rationalization etc.

quantifish commented 9 years ago

Any interest in the exploitation rate method here as well? i.e. Ut = Ct/Vt, Nat+1=Nat(1-UtSa) etc, obviously written for size rather than age...