Eastern Merced County is a fitting use for the cubic miles of rock the glaciers carved away in the course of digging the Yosemite country. While the topography is much more subdued, upon scrutiny the landscape reveals ecosystems that are every bit as integrated with their surroundings as the montane forests, boreal meadows, and alpine tundras a few score miles to the east.
Eastern Merced County is an area of hardscrabble soils and meager water supply. These facts have conspired against agricultural and urban development, allowing a largely intact landscape to persist as grazing land to the present day: the area encompasses the largest, least fragmented example of a vernal pool – grassland environment anywhere in the known world.
Eastern Merced County is home to some of California’s rarest, most endangered animals and plants. Some of these organisms are making their last stand here against extinction. Each of these species has specific adaptations and exacting habitat requirements. They are not found just anywhere; they are just found where conditions are right. To a large degree, regional patterns in these habitat conditions reflect differences in the parent materials deposited in Merced County through geologic time. Many of these organisms are so keenly adapted to their various preferred habitats that a good, skillfully interpreted geologic map can help explain where things do or do not live. This study presents such interpretations for 23 plants, six shrimp, four amphibians, an aquatic reptile, wintering- and breeding-birds, nine small mammals, and kit fox found during surveys of more than 40,000 acres on a dozen cooperating ranches scattered through out the region.
Eastern Merced County is a backyard jewel and the County of Merced is to be commended for embarking upon efforts to conserve the region. This study provides a much-needed synopsis of the complexities of the region’s vernal pools and other habitats, and will be a useful reference.
Robert F. Holland
Auburn, California
March 21, 2002