Impacts of conservation easements for threat abatement and fire management in a rural oak woodland landscape

Rural residential development can impact habitat and complicate fire management. Conservation easements are created to prevent development but are rarely assessed for their influence on development patterns. In the Lassen Foothills, California, The Nature Conservancy (TNC) holds over 37,000ha of mostly public-funded conservation easements on ranchland dominated by blue oak (Quercus douglasii) woodland. For this region we modeled land use through 2050 under two scenarios, with and without conservation easements, using a rule-based growth model. We mapped development footprints on 760 rural residential parcels through automated remote sensing. From calculated footprint sizes we projected site-level habitat loss for each scenario. We also projected the influence of development patterns on fire management. With easements present the Lassen Foothills would gain about 184 new homes, compared with 223 homes if easements were absent. With an average residential footprint size of 0.34 +/- 0.25 ha (mean +/- SD), we found that easements slightly reduce vegetation conversion, protecting an additional 16.8 ha than were protected by the general plan alone. Without easements, scattered development may alter fire management on 12,370 ha (17.5% of undeveloped wildfire containment areas) by requiring more fire suppression and reducing options for prescribed burning. Low development pressure and county land use policies maintain very low residential densities in the Lassen Foothills. The easement program may increase options for fire management by preserving large landscapes. This case illustrates the limited effectiveness of land acquisition in preventing development in a low-threat landscape, and demonstrates the utility of growth models for prioritizing conservation investments. Published by Elsevier B.V.