This pair of double-crested cormorants, one adult and one juvenile, perched on an exposed branch in Hughes Lake, Memorial (Third Ward) Park in Passaic on Sunday, 13th October.
The adult bird on the right is showing a behavior that is peculiar to cormorants. Cormorants feed by diving and swimming underwater searching for their prey. This requires that they be less buoyant than other aquatic birds. Cormorants lack the quantity of oil in their feathers that ducks and geese have, for example. Other features of their physiology also help them dive and remain underwater. The cormorants’ feathers absorb some water when they dive, so they dry their wing feathers by holding them out at their sides for extended periods of time.
The last time Jody and I went boating in Central Park we were accompanied on much of our excursion by a cormorant that swam behind the boat and dove frequently into the murky green water of The Lake.
Cormorants are common in North Jersey and often visit Hughes Lake, but range map in the Petersen guide and the range map on allaboutbirds.com would seem to indicate that cormorants do not nest in this area. It seems likely that these two are just passing through on their way to their winter home.