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Burrowing Owl The CDFG lists the burrowing owl (Athene cunicularia) as a Species of Special Concern. California's burrowing owl populations have declined as a result of urbanization of grasslands and pasture lands (Remsen 1978). Burrowing owls are semi-fossorial, nesting in abandoned ground squirrel burrows and hunting on agricultural lands and grasslands. Burrowing owls are relatively common in the Lodi area along the Mokelumne River and on farmlands (CLCDD 1988). These owls could potentially nest in ground squirrel burrows below the fence at the north end of the project site; however, they prefer open vistas from their burrows, and the wooden fence obscures vision and would probably inhibit use of these burrows by owls. No owls were detected on the project site during the wildlife survey, nor were there signs of owl activity around ground squirrel burrows. California Tiger Salamander The USFWS lists the California tiger salamander (Ambystoma tigrinum califomiense) as a Candidate Category 2. The tiger salamander is found in foothill and valley grassland habitats in central California, most commonly in the vicinity of ponds and vernal pools. The nearest CNDDB record for the occurrence of this species is a location approximately six miles north of the project area. Tiger salamanders lay eggs in vernal pools, ponds and slow-moving waters of the Central Valley and low elevation Sierra foothills. Egg-laying typically occurs during the winter rains from mid-December to February when pools and basins begin to fill with water. The eggs hatch into aquatic larvae that by late spring metamorphose into terrestrial adults. The adults leave their natal ponds and pools as the waters begin to dry in early summer. Tiger salamanders spend their summers avoiding desiccation by remaining in rodent burrows, cracks in soil, or under logs where soil remains moist. They stay in these refugia until late fall, venturing out only occasionally at night when conditions are cool and moist. There are no vernal pools or ponds on the proposed project site. Tiger salamanders could potentially use the pond that lies north of the project site, and use California ground squirrel burrows along the northern edge of the site as hibemacula. However, the pond and almost all of the ground squirrel burrows are not within the project site boundaries, so resident tiger salamanders would not be directly impacted by the expansion of the transfer station. Bank Swallow Bank swallows (Riperia riperia) are listed as a Species of Special Concern by CDFG. These colonial birds build nests in burrows where river erosion has produced steep, soft banks in natural levees. Riprapping has resulted in loss of nesting habitat and population densities in 9 1