Complex sentence: All madtom species, including "N. munitus" have experienced decline since the 1950s due to channelization, gravel mining, dredging, and siltation, which reduce the ability for the species to properly breed and survive.
Split into simpler sentences: All madtom species, including "Noturus munitus" have experienced much decline since the 1950s due to channelization, gravel mining, dredging, and siltation. These activities reduce the ability for the species to properly breed and survive.