Jasper Ridge Biological Preserve is a 1,190-acre Stanford University nature preserve and field station in Portola Valley, formally established in 1973. Encompassing Jasper Ridge, Searsville Lake, and parts of the San Francisquito Creek watershed, it serves both as protected landscape and as a center for research, teaching, and public education. Its hilly terrain and varied geology support an ecology shaped by major change, from chaparral cleared into grassland to expanding oak, madrone, Douglas fir, and second-growth redwood groves. Research facilities grew with the Leslie Shao-ming Sun Field Station in 2002, and studies there have addressed climate effects on grasslands, invasive ants, bats, and mountain lions.