The last seasonal presence of Mnemiopsis also tended to occur at the same station near the inner margins of Narragabsett Bay (fig.2, Table I). The most common stations to have the last seasonal appearance (n= 3) were locstion at the mouth of the Providence River (station 15), Greenwich Cove (station 3) and adjacent to Prudence Island (station 5). Due to the coarse time scale sampling, there were several instances (n= 5) when there were more than three station with the first or last seasonal presence of Mnemiopsis. However, no station in the central or exterior parts of Narragabsett Bay (station 5-12) ever had the first or last seasonal presence of Mnemiopsis without its co-occurrence at a station near the inner margins of the estuary. Similarly, when there were three or fewer station with the first or last seasonal presence, they were always stations from the inner margins of the estuary (station 1-3, 13-16).