Ecology

Large, unbroken forest is essential breeding ground for migratory neotropical birds such as the scarlet tanager.

Large, unbroken forest is essential breeding ground for migratory neotropical birds such as the scarlet tanager.

 The following excerpts are from “Smart Growth Planning and Management Project for the Sourland Mountain – A Conservation and Open Space Plan for the Sourland Mountain Region,” prepared by Bansich Associates, Inc., Sergeantsville, NJ, November 2005 (prepared with funding provided by the NJ Department of Community Affairs-Smart Growth Grant Program, NJ Office of Smart Growth).

Biological diversity is a reflection of the health of an ecosystem. The Sourland Mountain region hosts a wide variety of plant and animal species, within the extensive forest and rural landscape that provide the greatest block of contiguous forest habitat in the State’s Piedmont province.

The low permeability of the rocky Sourland terrain creates perched wetlands and vernal ponds.

The low permeability of the rocky Sourland terrain creates perched wetlands and vernal ponds.

Available biological data and pertinent scientific literature highlight the unique attributes that make the Sourland Mountain region so important as habitat, including:

  • The Sourland Mountain region is one of only three major areas of unbroken habitat in NJ, at a strategic location mid-way between the Highlands and the Pinelands.

  • The Sourland Mountain region is a critical stopover point for birds migrating along the Atlantic flyway and is one of New Jersey’s top fall migration stopover sites.

  • The region supports a great diversity of bird species, many of which are listed as either threatened or endangered, or are being tracked as species of special concern.

  • Vernal pools, isolated wetland depressions seasonally filled with water, are common in the Sourlands. Some of these are known breeding sites for a number of herptiles who require these pools for egg laying and early life stages.

  • The Sourland Mountain region may be the last refuge of some complex plant communities that once flourished in central NJ.

Sixteen plant species that are either endangered or of special concern in NJ have been documented in the Sourlands to date.

The Sourland Mountain region is unparalleled as an ecological island of unbroken habitat in central New Jersey, in part due to geological and hydrological features that hinder human encroachment and aided animals and plants.

Headwaters originating on the mountain provide riparian and aquatic habitat, and perched water table areas supply an ephemeral yet critical habitat for a number of specialized organisms. These habitat types, shaped by the geology and contours of the land, its soils and hydrology, are uniquely suited to sustain a diverse array of plants and animals. Nonetheless, man-made activities can easily impact many of these species and the biodiversity of the area.

The Sourlands provide ideal habitat for the wood turtle, a threatened species in New Jersey.

The Sourlands provide ideal habitat for the wood turtle, a threatened species in New Jersey.

The Sourland Mountain region is a reservoir of biodiversity. Not only does it provide prime habitat and a critical migration stopover site, but because it supports larger populations of many organisms, it can serve as a sour of genetic diversity for other populations of the same species that utilize small habitat patches nearby.

The mature forest that now covers the ridge is secondary growth that replaced the virgin old-growth forest that was logged many years ago. This pattern gives an historical record of the use and disuse of the fields and provides a wide variety of habitat types that support a remarkable diversity of animals and plants.

Removing the forest for farming or development, even in small patches, can have impacts extending up to 1,000 feet in all directions and creates an “edge effect,” where the deep woods habitat of the interior forest is fragmented and breeding bird habitat is threatened by increased nest predation. Many Sourland region species rely on both the quantity and the quality of the forest and understory, and will disappear as the forest becomes fragmented and degraded.