For Largemouth Bass in particular, their sense of smell is highly developed. In fact the commercialization of million dollar Bass fishing tournaments has led to leading scientific breakthroughs in the understanding of how well Largemouth Bass can smell and sense chemicals in the water and how they react to these smells.
http://freshwaterlures.blogspot.com/2009/06/how-well-can-largemouth-bass-smell.html
