Originally Posted by RecoveringScot
The number of food-distributing pelagics for one. In much the same way as Nuthatches have probably spread through garden feeders into Scotland in the last few years. Alter a bird's regular food supply and you may alter its distribution.
Just a guess mind.
Unfortunately the amount of food distributed from boats is going to be literally a drop in the ocean ...
Not a lot of chumming goes on, and what does would be a miniscule/negligible addition to the biomass/available food out there.
Nice guess tho!