Mill Creek Marsh

Mill Creek Marsh is 209-acre marshland. Saltmarsh and impoundments viewed from a broad, well-kept 2 km trail.

As long as there is open water, a good selection of winter waterfowl, especially American Green-winged Teal, is present. Raptors at this season include Cooper's Hawk and Red-tailed Hawk, Northern Harrier, and Peregrine Falcon. Rough-legged Hawk is occasionally seen over the marshes west of the Hackensack River, and there is a single record of a Snowy Owl. Passerine diversity is generally low in winter, with half a dozen New World sparrows (including Swamp Sparrow, Fox Sparrow, and White-crowned Sparrow) possible. Depending on cone crops to the north, wintering finches can include American Goldfinch, Pine Siskin, House Finch, and Purple Finch, which feed on the seed capsules of sweetgum trees. Yellow-bellied Sapsucker are reliable, especially in the tall cottonwoods at the southeast corner of the area.

Spring sees an increase in waterfowl numbers and diversity, with Northern Pintail, American Wigeon, Common Merganser, Hooded Merganser, and Ruddy Duck joining the mix. The first shorebirds, typically Greater Yellowlegs and Killdeer, arrive in March. April and early May see all of New Jersey’s common sandpipers and plovers, though the flocks are significantly smaller than they are at the beginning of the southbound migration in July. Almost every eastern wood warbler has been recorded here in May, though only a few species pause in large numbers.

Breeding birds at Mill Creek Marsh and in the surrounding wetlands include American Black Duck, Gadwall, Green-winged Teal, Ruddy Duck, Osprey, Bald Eagle, Eastern Kingbird, Warbling Vireo, Carolina Wren, Baltimore Oriole, and Common Yellowthroat. Willow Flycatcher, Tree Swallow, Marsh Wren, and Yellow Warbler are especially common and conspicuous.

Any of New Jersey’s heron and egret species can be seen at Mill Creek Marsh in summer, but only the Least Bittern breeds in the marsh; the others, including Yellow-crowned Night Heron, are commuters from nearby heronries or post-breeding wanderers. The most exciting avian phenomenon here is the fall shorebird migration, which begins in early to mid-July with the first southbound Greater Yellowlegs, Lesser Yellowlegs, Least Sandpiper and Semipalmated Sandpiper. A rising tide is essential for finding the largest numbers. The waters push the feeding birds to the western edge of the southern impoundment, where outstandingly close views and good photographs can be had. Of the twenty-two species recorded here thus far, Semipalmated Sandpipers are by far the most abundant of the migrants, with high counts of 6000 individuals or more crammed into this small area in the last days of July.

For so small and so notably urban a site, Mill Creek Marsh has accrued an impressive list of rarities over the years, among them Purple Gallinule, American Avocet, White Ibis, American White Pelican, Prairie Falcon (first New Jersey record), Brewer's Sparrow (first New Jersey record), Yellow-headed Blackbird, and Western Meadowlark.