| As Americans have sought voluntary, incentive-based approaches to conservation, conservation easements have dominated land conservation practice. Yet the social and ecological outcomes of conservation easements are largely unknown. This interdisciplinary dissertation extends lines of inquiry developed in public land policy and protected area planning to the analysis of conservation easement outcomes at multiple scales. A national survey of 119 easements held by The Nature Conservancy (TNC), the largest nonprofit easement holder in the United States, revealed the biodiversity protection goals and private uses on easement properties. Most easements (80%) aimed to provide habitat to protect species or communities, and nearly all were designed to reduce development. Some residential or commercial use, new structures, or subdivision of the property were permitted on 85% of sampled conservation easements. Nearly half (46%) were working landscape easements with ranching, forestry, or farming. These results demonstrated a need to raise public understanding of tradeoffs in the use of easements on private lands. At a regional scale, analysis of the San Francisco Bay Area protected lands spatial database revealed the different public benefits provided by easements compared with fee-simple properties. Easements complemented fee-simple protection by targeting working landscapes in oak woodlands, grasslands, and croplands. Conservation easements were accordingly more likely to be closed to public recreation and farther from urban areas than fee-simple properties. Furthermore, TNC's approach to adaptive ecosystem management and governance of working landscape easements in California oak woodlands and grasslands changed significantly between 1983 and 2006. Detailed analysis of easement documents and conservation practitioner interviews for 47 rangeland easements showed that easement terms related to land management increased in detail and complexity over time, particularly for purchased easements on private land. Specific grazing terms restricted residual dry matter (51%), type of grazing animal (49%), and season of grazing (32%). Increasingly, TNC acquired significant land management control while providing limited mechanisms for flexibility. Finally, based on improved understanding of easements and their land base, methods for a simplified but consistent ecological monitoring program for oak woodland easement properties in northern California were developed. |
