Summary of the outputs of the final GAM for the density index (N/km²).

Explanatory variables included the single effect of factor Time of the Day (ToD) and Fishery, Year-Fishery interaction (Yr:Fishery) for each level of the factor (“Y” fishery allowed, “L” limited fishery, “N” fishery ban), longitude (Y), depth (D), percentage of dissolved oxygen (Oxy) and salinity (Sal); “SE”, standard error; “edf”, estimated degrees of freedom; “df”, degrees of freedom.