I mean, there's certainly an issue between what we're seeing on the ground and what's reported by the science. If you don't have enough indices or data entry points going into your model, you can have the best model in the world, but what will come out of it will be missing a lot of good information.
I'll give you the example of eggs. If you use egg count to estimate the eventual spawning stock biomass of any species, nobody knows, with the changing ecosystem from year to year, how the survival of the eggs will change. We've seen this in lobster, for instance, over the last 20 years. The ecosystem for lobster has been very positive for egg survival but also larval survival to juvenile size.
There are a lot of changes going on in the ecosystem right now that might explain why mackerel are in abundance. They're not necessarily there at the time you're looking for them at the egg level, juvenile level or adult level.