Urban Biodiversity: The Natural History of the New Jersey Meadowlands

Abstract

When many people hear the name New Jersey—especially those who are not familiar with the Garden State—the words conjure a stereotypical image of a landscape of refineries, clogged freeways, urban sprawl, and polluted waterways. In some places, the image is not wholly inaccurate. The extensive marshlands along the lower reaches of the Hackensack River—the eponymous Meadowlands—have been extensively filled, channelized, and developed for over three centuries. Two very heavily traveled spurs of the New Jersey Turnpike (Interstate 95) cut through the heart of the wetlands, bringing the landfills, factories, residential and commercial development, and wetlands now dominated by seeming monocultures of common reed (Phragmites australis) front and center to millions of travelers every year. Yet, as authors Erik Kiviat and Kristi MacDonald make clear in this excellent book, a vibrant and biodiverse ecosystem persists amid the urban infrastructure located less than five miles west of Manhattan. The Meadowlands are a result of continental glaciation. As the final Pleistocene glacier advanced, it gouged a north–south oriented valley. On its eastern side, the valley was confined by the resistant diabase sill now recognized as the Palisades along the Hudson River opposite Manhattan. On its western side, the valley was separated from its neighboring drainage (now occupied by the Passaic River) by a sandstone ridge. As the glacier began to melt back northward, a terminal moraine blocked the valley’s southward drainage toward the ocean, forming a deep freshwater impoundment, Glacial Lake Hackensack. Soil carried downstream into the lake from the retreating glacial front deposited layers of rich, unconsolidated sediment. Approximately 10,000 years ago, the lake breached and began to drain. At that time, the Meadowlands became a broad, forested valley crossed by numerous meandering freshwater tributaries draining into the newly formed Hackensack River. After centuries of rising sea levels, the Atlantic Ocean encroached on the lower portions of the valley, forming the Hackensack River estuary. About 1000 years ago, sea level rose to near contemporary levels. The rising waters flooded and killed most of the Meadowlands’ forests. The forests were replaced by tidal fresh and brackish marshes dominated by cordgrasses (Spartina spp.)—hence the Meadowlands name. Patches of Atlantic white cedar (Chamaecyparis thyoides) remained where soil and moisture conditions allowed the trees to persist. Tidal marshlands and cedar swamps were the prevailing habitat types until the estuary was modified by Dutch and English colonists through filling, burning, lumbering, diking, and ditching. The Meadowlands’ proximity to the rapidly developing city of New York guaranteed their urbanized fate. The authors consider the Meadowlands in two geographic contexts: the Core Meadowlands and the Greater Meadowlands. The Core (79 km) encompasses the broad estuarine and formerly estuarine wetlands and wetland fill alongside the Hackensack River. This is the area for which the most biological information is available. The Core is roughly coincident with the state-designated Meadowlands District, a planning jurisdiction.