Great Limestone Valley

Conservation Area Plan: Introductory Information

Conservation Area Name:

• Great Limestone Valley

Total Acreage:

• 256,329 acres (401 square miles; 104,000 hectares)

PortfolioSummary:

• Portfolio Sites – 32
• Matrix Blocks – 2 (portions of Swartswood and Kittatinny blocks)
• Targets – 12
• Target occurrences – 38

County/State:  

• Sussex and Warren Counties, New Jersey

 Planning Team:

• Paul Brangs, The Nature Conservancy of New Jersey
• Louise Galasso, The Nature Conservancy of New Jersey
• Albert Joerger, The Nature Conservancy of New Jersey
• Holly Muller, The Nature Conservancy of New Jersey
• Angela Shoemake, The Nature Conservancy of New Jersey
• Michael Van Clef, The Nature Conservancy of New Jersey
• Keri VanSchaften, The Nature Conservancy of New Jersey

Executive Summary

Conservation Value

The Great Limestone Valley Conservation Area encompasses 256,000 acres in Warren and Sussex Counties, New Jersey. This unique area is characterized by northeast-southwest oriented ridge formations, rock outcroppings, pinnacles, sinkholes, and caves found over veins of limestone-rich bedrock. The area is extremely important due to accepted occurrences of twelve Lower New England/Northern  Piedmont primary ecoregional targets (bog turtle, dwarf wedgemussel, Northern metalmark, Schweitzer’s  buckmoth, basil mountain-mint, a rare blackberry species, false hop sedge, calcareous fen community, dry-mesic calcareous forest community, inland calcareous pondshore community, terrestrial cave community) at 32 portfolio sites. The overall Site Biodiversity Health Rank is “Good”.

The Great Limestone Valley is home to 162 breeding bird species , 72 fish species, 49 species of amphibians/reptiles,  83 butterflies, 76 dragonfly/damselfly  species, 292 woody plants, 33 plant communities, and 33 mammals including black bear, red fox, gray fox, bobcat, and coyote.  A large number of state listed species (30 vertebrate animals, 17 invertebrate animals, 171 plant species, and 11 communities) are also found within the Great Limestone Valley.  There are a total of 736 occurrences of rare species and communities.  At least one occurrence of rare species/communities can be found in sixty percent of the 360-acre grids used by the New Jersey Natural Heritage Program.

The Challenge

The most critical threat to the Great Limestone Valley is primary home development.  Important stresses created by this threat include habitat destruction, habitat fragmentation, excessive groundwater withdrawal, and creation of toxins and nutrient loading. A second critical threat is invasive species, which may lead to severe degradation of conservation targets. Other threats include forestry practices, crop production practices, poaching, and recreational vehicles .

Although this site is largely rural and agricultural, it is experiencing a rapid conversion of farmland into residential development. The demand for housing in this area is primarily from young families looking for affordable housing. This development pressure is expected to persist as long as the rise in land values continues to outpace the economic benefits of farming in New Jersey.

The Nature Conservancy of New Jersey, along with various stakeholders, has made progress by protecting 1,780 acres of priority habitat through the creation of seven preserves within the Great Limestone Valley.  An additional 44,808 acres has been permanently protected through a variety of arrangements, including 18,102 acres in farmland preservation, 5,003 as National Wildlife Refuge, 19,049 acres in State Park, Forest and Wildlife Management areas, 594 acres in municipal parks, 1,517 acres in other non-profit preserves and 543 acres in conservation easements.  However, only 18 percent of the Great Limestone Valley Conservation Area has been permanently protected from future development. Given the pressures of suburban sprawl, it will be essential to act swiftly over the next 10 years to continue to increase the boundaries of the Conservancy’s preserves, support farmland  preservation while  promoting environmentally compatible farming practices and work with all levels of government to ensure the long-term viability of this significant area.

The Solution

The Nature Conservancy of New Jersey will combat these threats through a combination of acquisitions of priority habitat and conservation easements, building partnerships and funding opportunities, stewardship for invasive species control and continuing education and outreach. Over the next 10 years, changes in land use will be monitored to determine the impact of the conservation strategies at the landscape level.  Individual targets will be monitored to measure their viability, as well as abatement of their critical threats.  It is highly likely to achieve conservation success in the Great Limestone Valley Conservation Area through continued conservation planning and implementation.