I recall reading Striper uses sudden opening of the mouth "vacuuming technique" when eating.
I live in southern Finland and unfortunately I can not go after Atlantic Salmon every year. Lately my primary fish has been Pike which does not hook very well to short hook flies but often Pike does not give up and can hit multiple times. I have tied Intruder type flies for Pike using Steel wire to connect the hook. I am coming to Cape Cod soon and will take some of my slimmer Pike flies to use for Stripers.