Flowing through the bottom of the Dawson Los Monos Canyon Reserve is Agua Hedionda Creek, one of the few perennial streams in Southern California, as it winds its way through the San Diego county foothills to the Pacific Ocean. Along the stream banks of the canyon floor grows a lush riparian woodland, which gives way to dense chaparral spreading up the steep north- and south-facing slopes. The wide upper canyon opens out onto old pastures of introduced annual grasses, the result of a century of grazing. Other reserve habitats, some of which were once common throughout Southern California, include coast live oak woodland, inland sage scrub, and a mixed grassland of native bunchgrasses and introduced annuals. Downstream from the reserve’s western boundary lie the coastal wetlands of the Agua Hedionda Lagoon, which are preserved through state and federal legislation. These neighboring protected lands enable the movement of species between open spaces, which in turn encourages diversity and helps keep the reserve from becoming an isolated natural island in this growing region. The varied landscape of Los Monos Canyon supports a rich fauna, with more than 75 species of birds, including several pairs of nesting black-shouldered kites.