It is doubtful that a timeline record of Double-crested Cormorants (DCCO) at Boonton Reservoir exists. Consider it started as of today. 300 DCCOs were at the Reservoir – mostly on the north and south sides of the island with others scattered throughout the Reservoir. Of course, this is a speck in the ocean compared to coastal migration counts (35,500 at Cape May Hawkwatch, Oct. 17, 2009) but this is easily the highest count recorded for summering residents in Morris and Somerset Counties according to the eBird database. As far as is known, this is also the highest count, so far, for July 2012 from any one location in New Jersey. Phalacrocorax auritus has come a long way in the Mocosoco area. (Click on the photo for a larger image)

(Photo by J. Klizas)

I think the state and perhaps NJAS (Kane) surveyed both the Cormorants and the Great Blue Heron colony in the early stages.