Spangled Frittilary on Swamp Milkweed


PNHP methodology follows that of Natural Heritage Network and NatureServe. This international network links programs in all 50 states, 6 Canadian Provinces, and 12 countries in Latin America and the Caribbean. Standard data collection and transcription procedures are used through the network. Use of consistent methodology presents an opportunity to assess the status of a given species or natural community over a broad geographic area across any number of political boundaries. Conservation strategies can then be developed at the local, state, or national level or may target an ecological unit.

Species records and associated locational information are initially gathered from plant and animal specimens maintained in museums, universities, and personal collections. These data are supplemented by research, publications , and communication with knowledgeable individuals. Intensive field surveys are conducted to verify historically known plant and animal sites and to search for previously undocumented locations. Natural communities can be located through species records or a variety of other sources including air photos, soil surveys, and geologic maps. Field surveys are then conducted to identify component species and gather ecological data. Through this science-driven inventory, vital ecological resources, and sites rich in natural diversity are identified and monitored for future conservation efforts.

PNHP works with the academic community to validate information and ensure that the highest possible standards are maintained with regard to accuracy of data. We rely upon the Pennsylvania Biological Survey for proposed status ranks. The PBS and others also assist the program by providing review of data and methods.