Either scenario, 1 or 2, allows for a comparison of the relative values of estimated effort and LPUE within a time series.
Squid abundance, measured as LPUE, also showed a pronounced drop and rapid increase in response to the El Nino.
Indeed, the high LPUE in the present study in late 1999 and early 2000 points to increased squid abundance in response to a more productive environment.
We were concerned that an underestimation of effort along the mainland coast would explain this study's post-El Nino increase in LPUE.
In this case, the absolute values of estimated effort and LPUE would be underestimated across all dates.