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APPENDICES <br />City of Redwood City, Public Works Division Initial Study & Mitigated Negative Declaration <br /> <br /> 4 Blankinship & Associates, Inc. <br /> <br /> <br />Yellow warbler (Setophaga petechial) <br />Yellow warbler inhabit scrub-shrug wetlands, forested wetlands, open scrub, second-growth woodlands, and <br />thickets (NatureServe 2014). Nests are placed in upright forks or crotches of bushes, saplings, or large trees, <br />from less than a meter above ground to high in tall trees. Nesting locations are chosen based primarily on <br />characteristics of the vegetation patch rather than the characteristic of the nest plant itself. They primarily eat <br />terrestrial insects (especially caterpillars) and spiders, taking most food items from leaves or bark. Because their <br />food base consists of terrestrial species, yellow warblers are not likely to be exposed to copper-containing- <br />algaecides and/or aquatic herbicides applied to the Lagoon. <br /> <br />California least tern (Sternula antillarum browni) <br />California least tern inhabit seacoasts, beaches, bays, estuaries, lagoons, lakes, and rivers (NatureServe 2014). <br />They usually nest on open, flat beaches along lagoon or estuary margins. The species eats mainly small fish <br />obtained by diving from air into shallow water. Given the large amount of potential foraging area, the food <br />items from treated areas would likely only contribute an insignificant percentage of the total diet. Therefore, the <br />risk posed by copper-containing algaecides and/or aquatic herbicides applied to the Lagoon is insignificant. <br /> <br /> <br />Fish <br /> <br />Tidewater Goby (Eucyclogobius newberryi) <br />Tidewater gobies are found in shallow lagoons and lower stream reaches where the water is brackish to fresh <br />and slow-moving or fairly still, but not stagnant. Their salinity preference is usually <10 parts per thousand – <br />ppt. They avoid open areas where there is strong wave action or strong currents. Tidewater gobies are capable <br />of living in saline water ranging from 0 to over 50 ppt salinity and at temperatures of 8-23°C. Suitable water <br />conditions for nesting have been reported as 5-10 ppt salinity and 18-22°C temperatures. Water depth in <br />tidewater goby habitat ranges from 25-100 cm and dissolved oxygen is fairly high. Gobies sometimes can <br />persist, however, under anoxic conditions and have been observed to come up and gulp air at the water surface. <br />The substrate usually consists of sand and mud, with abundant emergent and submerged vegetation. Severe <br />salinity changes and tidal or flow fluctuations have a detrimental effect on the survival of tidewater gobies, <br />resulting in population declines (Moyle et al. 1995). According to the February 6, 2013 Final Rule issued by <br />USFWS, no designated Critical Habitat occurs within the San Francisco Bay. Accordingly, no exposure of <br />tidewater gobies to copper-containing algaecides and/or aquatic herbicides is expected; therefore, no risk is <br />anticipated. <br /> <br />Eulachon (Thaleichthys pacificus) <br />Eulachon are anadromous fish that may be found in bays, sounds, rivers, near shore, and coastal inlets <br />(NatureServe 2014). They migrate short distances up coastal streams to spawn in coastal freshwater streams <br />over bottoms of silt, sand, gravel, cobble, or detritus. Spawning migrations usually occur in April or May, often <br />corresponding to high tides. They are mainly particulate feeders that consume primarily marine euphausiid <br />crustaceans. Young fish eat mostly copepod larvae, phytoplankton, copepods, and other zooplankton, but may <br />also eat smaller eulachon larvae. According to the January 5, 2011 Critical Habitat proposal issued by USFWS, <br />no designated Critical Habitat occurs within the San Francisco Bay (USFWS 2015). Accordingly, no exposure <br />of eulachon to copper-containing algaecides and/or aquatic herbicides is expected; therefore, no risk is <br />anticipated.. <br /> <br />Longfin smelt (Spirinchus thaleichthys) <br />Longfin smelt are anadromous fish that spend their adult life in bays, estuaries, and nearshore coastal areas, and <br />migrate into freshwater rivers to spawn (CDFG 2009). Spawning migrations occur primarily from January <br />through March, in the Delta. Newly hatched larvae may be swept downstream into brackish waters and stay in <br />areas where fresh and salt water mix. Adults may be found in a wide range of salinities and primarily feed on <br />small crustaceans and fishes (NatureServe 2014). The typical length of longfin smelt is 3.5 to 4.3 inches, <br />although third-year females may grow up to 5.9 inches (USFWS 2012). Adults prefer salinities of 15 to 30 ppt <br />(CNDDB 2012). Although larval and juvenile longfin smelt are unlikely to enter the Lagoon due to significant <br />6.3.A. - Page 73