However, as Berger pointed out in his work, there are numerous problems with making maps of global ocean productivity. Setting aside all the problems, I do not see many positive correlations. There does not seem to be a very strong relationship between areas of low productivity and areas of few cephalopod species. Also note that these areas tend to be big fisheries. For reasons unknown to me, there is a notable absence of cephalopods all along the western coast of North and South America.
More study needs to be done in order to effectively model the distribution of cephalopods.
The first place to start would be to look at other variables that affect the population dynamics of cephalopods. Water depth, salinity, water temperature, sediment load, and other biologic variables should be considered.