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tokami / StockMonitoringTool

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Natural mortality dropdown box (Expert) #44

Open aenieblas opened 3 years ago

aenieblas commented 3 years ago

(Expert) Only 3 methods available in the drop-down - these are the only ones available in TropFishR?

aenieblas commented 3 years ago

(Expert) Do you find the natural mortality supporting tool useful for user comprehension? I.e. comparing the difference between different methodologies of estimating natural mortality, or would you recommend removing it from the SMT?

tokami commented 3 years ago

There are more methods available in TropFishR, but those are ones most meaningful in the scope of a length-based stock assessment routine. All estimators dependent on maximum age have to be treated careful as length measurements alone do not alone to derive absolute ages or the maximum age (depend on t0 which cannot be estimated from length data alone). Lorenzen and Gislason would be very relevant and would provide nat mort by length but further work is needed to include that in the SMT.

I think the nat mort option in the supporting information is interesting and useful for teaching. For assessment purposes it might be rather confusing and those values should not be used from FishBase blindly.