INDICATORS ASSESSMENT FOR HABITAT CONSERVATION PLAN OF YOLO COUNTY, CALIFORNIA, USA

Whereas habitat conservation plans (HCPs) have been intended to provid e comprehensive environmental mitigation for multiple species, they of ten narrow in focus to one species and either one mitigation site or u nspecified sites. We developed an indicators framework from which to r ate land units for their ecological integrity, collateral values (nonb iological qualities that can improve conservation), and restoration an d conservation opportunities. The ratings of land units were guided by the tenets of conservation biology and principles of landscape and ec osystem ecology, and they were made using existing physical and floral information managed on a GIS. As an example of how the indicators app roach can be used for HCPs, the 29 legally rare species targeted by th e Yolo County HCP were each associated with vegetation complexes and a gricultural crops, the maps of which were used for rating some of the landscape indices. The ratings were mapped so that mitigation can be d irected to the places on the landscape where the legally rare species should benefit most from conservation practices. The most highly rated land units for conservation opportunity occurred along streams and sl oughs, especially where they emerged from the foothills and entered th e Central Valley and where the two largest creeks intersected the Sacr amento River flood basin. We recommend that priority be given to mitig ation or conservation at the most highly rated land units. The indices were easy to measure and can be used with other tools to monitor the mitigation success. The indicators framework can be applied to other l arge-area planning efforts with some modifications.