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Soil Investigations for Data Collection in the Delta Initial Study/Proposed Mitigated Negative Declaration 54 inches SVL. It ranges in coloration from olive drab to black with a dorsal and a side stripe that can range from bright to muted orange or yellow or in some cases be absent, a light-colored ventral surface, and keeled scales (Nafis 2019). Giant garter snakes historically occurred throughout the Central Valley of California, although its current range has been reduced to fragmented populations from Glenn County to the edge of the Delta, and south from Merced to Fresno Counties. Giant garter snakes are a highly aquatic, diurnal snake, relying on the presence of water throughout the summer months, and are found in marshes, sloughs, rice fields, and other water bodies with emergent vegetation, a suitable prey base and associated upland with burrows, crevices or rip-rap for use as refugia. While they are generally underground in refugia during the winter, they are not fully dormant during that time. Breeding occurs shortly after emergence in March or April, depending upon the weather, with females giving birth to offspring between late July and early September. Giant garter snake has a high potential to occur within the Study Area based upon presence of suitable aquatic habitat and upland refugia and proximity to reported occurrences. There are several reported occurrences of Giant garter snake from less than 0.5 mile to 2 miles from multiple Impact Areas along the length of the Study Area. Implementation of mitigation measures to avoid impacts to all suitable aquatic habitat (MM BIO-1 and MM BIO-14), upland refugia habitat (MM BIO-2), and individuals that could be moving through the Study Area (MM BIO-1, MM BIO-2, and MM BIO-4) would reduce potential project impacts giant garter snake to: Less than Significant with Mitigation Incorporated. MM BIO-4: Giant garter snake a. Upland habitat within 200 feet of suitable aquatic habitat, that is suitable for giant garter snake (containing cracks or rodent burrows) will be flagged and avoided. b. On-land soil investigations within suitable upland habitat for giant garter snake will be conducted during the snakes active season of May 1 through October 1. Cormorants, Herons, and Egrets: Great Egret (Ardea alba), Great Blue Heron (Ardea herodias), Snowy Egret (Egretta thula), Black-crowned Night Heron (Nycticorax nycticorax), Double-crested Cormorant (Phalacrocorax auritus) Tree-nesting waterbirds, specifically, Double-crested Cormorant, Great Blue Heron, Great Egret, Snowy Egret, and Black-crowned Night Heron, typically use