Hi,
I'm working in stock assessment of a shrimp. There are several years of
survey information and I am considering the density (kg/km2) as abundance
indicator. I am using an integrated catch-at-length model that also
includes the fishery informarion. Usually when we do the assessment, we
consider two independent zones and this means the catchability is different
by zone. Nevertheless if we believe this abundance index is a good
representation of local densities, Can we suppose the catchabilities should
be differents?. I am thinking that could be better consider a single
catchability, the same for both zones, so the local abundances will have a
better representation.
Thanks a lot by your comments
Cristian
