Friday, July 08, 2005

Not-so Common Moorhen

Over the extended weekend I travelled out of town to visit family in New Jersey and New York. While there, I had the opportunity to bird with some family members in the Hackensack Meadowlands. If your experience of New Jersey is limited to the New Jersey Turnpike, wildlife viewing in the Meadowlands might seem a crazy idea. Many of the industrial sites and landfills that provide the "scenery" for the upper Turnpike are still there, but the state has been trying to preserve and expand the marshland set aside for wildlife refuge refuges and for wildlife viewing areas. (Here is a map.) Currently there are several locations accessible to birders; the best are described in William Boyle's Guide to Bird Finding in New Jersey. Birding in the Meadowlands is somewhat disconcerting, as it is hard to get away from the sound of heavy automobile traffic on the Turnpike, train traffic on the various railroads crisscrossing the marshes, and airplane traffic landing and taking off from Newark International Airport. The human hand has obviously fallen very heavily upon this area. But there are also some very beautiful spots; in some places there are vistas of acres of marsh grasses bending before the frequent breezes.

The Meadowlands provides important habitat for migrants and breeding birds. In the spring and late summer it becomes a stopover point for migrating shorebirds and herons. The Sawmill Creek mudflats, visible from De Korte Park, fill with these wading birds during the month of August. Early July is a little too soon for migrants, but a solitary greater yellowlegs may have been an early migrant. A few snowy egrets were also probably part of a post-nesting dispersal.

Because of its unique habitat combination, the Meadowlands is home to several birds, particularly waterfowl, that breed there and in few other places in New Jersey. Ruddy ducks are annual breeders; on Sunday a large flock was at De Korte and a few others were in Kearny Marsh. The latter site also held a female gadwall with several chicks in tow. Mute swans, an invasive species, are found reliably in the Meadowlands; about two dozen were at Kearny Marsh, and a few others were at De Korte. Empidonax flycatchers are not uncommon in New Jersey, but worth mentioning anyway. I saw one empidonax in Kearny Marsh. It was silent the whole time I watched it, so I cannot be certain of the identification, but given the habitat the bird was most likely a willow flycatcher. At Kearny Marsh, a least tern (endangered in New Jersey) patrolled the river and the impoundments.

Another Meadowlands specialty is the common moorhen. Someone else spotted it first as it crossed the path between two impoundments in Kearny Marsh. Later I got to see it while I was walking back along the same path. It emerged from the reeds on the left side of the path, and then stood in the middle of the path for some time before disappearing into the reeds on the right side of the path. It later walked out onto the path again. This was not my first sighting of a moorhen; my first was on the same day I saw my first purple gallinule, at Hughes Hollow near Washington last summer.

Since the first time I saw an American coot, I have considered coots to be very amusing birds. The same is true for moorhens. Their call is unusual; moorhen vocalizations sound a bit like squeaky toys, while coots make a clucking sound. Their head-bobbing gait - both on land and in the water - exaggerates the effect of the oddly-shaped frontal shield on their heads.

Unlike coots, moorhens are difficult to see. Their cryptic coloration (brown wings with a slate-gray body) makes it easy for them for disappear among marsh grasses. More importantly, even though they are found throughout the eastern United States, their distribution tends to be very local. The Meadowlands is, in fact, one of the few locations in New Jersey where moorhens breed. See Walsh et al., Birds of New Jersey. (The old edition of the Atlas of the Breeding Birds of Maryland and the District of Columbia also found few locations for breeding moorhens in Maryland.) The reason is that moorhens require specialized habitat that is found in very few places. While not endangered, this species' future survival depends on preservation of sufficient wetland areas.