It’s the deeper water just south of the River mouth Running along the Canadian Side. They pull a lot of big Hens out of there, hence the term cow pasture...
I know exactly where you are talking about, i lived on our family boat docked in Little River directly across from the boat launches and would see the guys fishing that area every morning around 5 am.
The guys were like machines, catch their limit in an hour then race in pull the boat race home and back within a half hour and do it again.