Hmmm. Interesting question. Without knowing the catchability coefficient makes it difficult. The catch and catch per unit effort are proportional to the abundance/biomass of your fish stock and are often only used as relative abundance indicies. You could try searching the literature for the catchability coefficient of other similar cuttlefish fisheries. If there appears to be low variability between fisheries then you might be able to apply that coefficient to the CPUE abundance equation. Another way, if you have data on fecundity rates etc would be to model the population for the two year period and work backwards to solve for fish biomass.

Hi,

Have you heard about the two-stage biomass model? It is based on assumptions about a simplified life cycle, and the idea is to model biomass dynamic between two stages of the stock (in the English Channel we use it between age 1 and age 2 because we consider a life-cycle of 2 years). You can set priors on the catchability, and the model fit will give you an estimate of the catchability according to the LPUE and survey data. I'm not sure you do have survey data, but you could adapt the model to your data.

Natheer Alabsi:

Please check "Manual on estimation of selectivity for gillnet and longline gear in abundance surveys".

Or contact to Dr Matsuoka in Kagoshima University

good luck

Natheer Alabsi:

Please check "Manual on estimation of selectivity for gillnet and longline gear in abundance surveys".

Or contact to Dr Matsuoka in Kagoshima University

good luck