Desilva Island
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SOUTH SAN FRANCISCO BAY 187 SOUTH SAN FRANCISCO BAY 188 SOUTH SAN FRANCISCO BAY SOUTH SAN FRANCISCO BAY This subregion includes shoreline areas from the Oakland Bay Bridge south to San Jose. Most of the tidal marshland in the South San Francisco Bay was diked and drained for pasture in the early 1900s and eventually converted to salt evaporation ponds. Planning efforts are underway to restore much of the marshland in this area to tidal action, although some ponds will be managed as non-tidal wildlife areas. Black- Active Great crowned Little or year Site Blue Great Snowy Night- Cattle Blue last # Colony Site Heron Egret Egret Heron Egret Heron County active Page 801 Alameda NWR Alameda Active 190 802 Artesian Slough Santa Clara 2002 191 803 Bair Island North San Mateo 1994 193 804 Bair Island South San Mateo Active 195 805 Baumberg 13 Alameda 2002 197 806 Baumberg 6B Alameda Active 198 807 Baumberg 8A Alameda 1996 218 808 Burlingame San Mateo 2000 218 809 Charleston Slough Santa Clara 1993 218 810 Coyote Creek Santa Clara 2003 199 811 Coyote Creek Lagoon Santa Clara 2002 200 812 Greco Island San Mateo 1998 219 813 Guadalupe Slough Santa Clara 2003 219 814 Hayward Shoreline Alameda Active 202 815 Lake Elizabeth Santa Clara Active 204 816 Lake Merritt Alameda Active 206 817 Moffett A2E Santa Clara 1995 219 818 Moffett A2W Santa Clara 1999 219 819 Moffett A3N/B2 Santa Clara 1996 220 820 Ovation Court Santa Clara Active 220 821 Oyster Cove Pier San Mateo Active 208 Palo Alto Baylands 822 Santa Clara Active 209 Duck Pond 823 Portola Valley San Mateo Active 211 824 Quarry Lakes Santa Clara 1995 212 825 Redwood Shores San Mateo 2004 213 826 Ruus Park Alameda Active 215 827 Shorebird Way Santa Clara Active 216 828 Steinberger Slough San Mateo Active 217 SOUTH SAN FRANCISCO BAY 189 190 SOUTH SAN FRANCISCO BAY Alameda NWR Great Blue Herons nest on a pier at the proposed Alameda National Wildlife Refuge, on the old Alameda Naval Air Station. The pier is an extension of the runway lights approximately 100 m over the bay. The herons are potential nest predators at a nearby breeding colony of the endangered California Least Tern ( Ownership: public Public observationSterna areas: antillarumnone browni Latitude / Longitude: N 37.7740 / W 122.3128 FocalNest survivorship nest survivorship (± SE) 1.0 ). 0.8 Gr e a t B lue He r on 0.6 0.4 0.2 0 xxxxxxxxxxxxx x 1993 = no data. Peak nestling19 9count4 (colony total) 50 1995 1996 Colony site description 40 1997 Topography: wetland 1998 30 Length x width: 182 m x 1.2 m 1999 Nest substrate: wooden pier 2000 20 2001 Average nest height: 5.5 m 10 2002 Trees (dbh): none 2003 Maximum tree canopy height: no canopy 0 2004 Vegetation cover: none xxxxxxx xx xx x 2005 x 1991 = no data. Evidence of disturbance Peak number199 2of active nests Western Gulls: potential source 50 1993 a 1994 Possible disturbance sugg 40 1995 1996 (see references in Methods). 30 1997 1998 Land use 20 1999 2000 10 2001 2002 Land Use ested by publisheda accounts 2003 0 Industrial 2004 xxxxxxx xx xx x 2005 Protected natural area x 1991 = no data. Distance from colony site (m) 1992 1993 0- 1994 100 1995 100- 1996 200 1997 X 200- 1998 X 1999 500 500- 2000 X 2001 1000 2002 X 2003 2004 2005 Artesian Slough This site, also known as brackish marsh, 1.5 km north of Alviso and 6.5 km east of San Francisco Bay on the Don Edwards National Wildlife Refuge. Fresh water is discharged into the slough Clara Water Treatment Plant. Little Blue Herons nested here in 1988, 1990, 1993, 1996 Mallardand 1998. Slough, is in a Ownership: public Public observation areas: none Latitude / Longitude: N 37.4460 / W 121.9642from the San Jose-Santa Colony site description SOUTH SAN FRANCISCO BAY Topography: wetland Length x width: 250 m x 150 m Nest substrate: California bulrush ( Averagecalifornicus nest height: not measured Trees (dbh): none Maximum tree canopy height: no canopy ) Vegetation cover: not measured 191 Schoenoplectus Black-crowned Night- Heron Evidence of disturbance Peak nestling count (colony total) Human activity (discharge from wastewater 500 treatment plant): potential source a 400 Possible disturbance sugges references in Methods) 300 Land use 200 100 Snowy Egret Land Use 0 Protected natural area ted by published accounts (see xxxx a xxxx 1984 (Nest survivorship data are notDistance available) from colony site (m) Peak number of activexxxx nests 500 1985 0- xxxx 100 1986 100- 400 xxxx X 1987 200 xxxx 200- 300 1988 X 500 200 1989 1990 xx X 500- 1000 100 1991 xx xxxx X 1992 0 1993 1994 1984 1995 1985 xxxx x 1996 = no data. 1986 1997 1987 1998 xxxx xxxx 1988 1999 1989 2000 xxxx 1990 2001 xx 1991 2002 xxxx xx 1992 2003 xx 1993 2004 xx 1994 (continued 2005 1995 x 1996 = no data. ) 1997 1998 1999 2000 xxxx 2001 2002 xxxx xx 2003 xx 2004 xx 2005 192 SOUTH SAN FRANCISCO BAY Artesian Slough Cattle Egret Peak nestling count (colony total) 50 40 Little Blue Heron 30 (continued) 20 10 0 (Nest survivorship data are not available) xxxx 1984 xxxx Peak number1 9of8 5activexxxx nests 50 xxxx 1986 40 1987 xxxx 30 1988 1989 xxxx 20 1990 xxxx xxxx 10 1991 1992 xx 0 1993 xxxxxx xx 1994 1984 1995 1985 xx x Peak nestlingGr e a t Egr count e t (colony total) 1996 = no data. 100 1986 1997 1987 1998 xxxx xxxx 80 1988 1999 1989 xxxx 60 (Nest survivorship data are not available) 2000 1990 xx 40 2001 1991 2002 xxxx xx 20 1992 2003 xx 1993 2004 xx 0 1994 x 2005 1995 1984 xxx x Peak number of active nests 1996 = no data. 100 1985 1997 1986 1998 x x x 80 1987 1999 60 1988 2000 1989 2001 40 xxx 1990 2002 xxxx xx 20 1991 2003 xxxx 1992 xx 0 2004 1993 2005 1994 1984 1995 1985 x 1996 = no data. 1986 1997 1987 1998 1988 1999 x 1989 2000 x x 1990 2001 1991 2002 xxx 1992 2003 1993 2004 1994 2005 1995 x 1996 = no data. 1997 1998 1999 2000 2001 2002 xxx 2003 2004 2005 Bair Island North This colony was on Don Edwards San Francisco Bay National Wildlife Refuge 6 km north of Redwood City, adjacent to Redwood Creek, and 0.3 km from San Francisco Bay. The South Bay’s largest mixed species colony existed here from at least 1982-1991, after which it was abandoned, apparently in response to predation by red fox. Ownership: public Public observation areas: none Latitude / Longitude: N 37.5345 / W 122.1993 SOUTH SAN FRANCISCO BAY Colony site description Topography: levee Length x width: 125 m x 28 m Nest substrate: coyote brush ( Average nest height: 2 m Trees (dbh): none Maximum tree canopy height: no canopy Vegetation cover: tree 0%, shrub 78%, ground 48% 193 Baccharis pilularis Black-crowned Night- Heron Peak nestling count (colony total) 500 Evidence of disturbance 400 Red fox: colony abandonment ) 300 Land use 200 Snowy Egret 100 Land Use Protected natural area 0 xxxx xxxx Distance from colony site (m) 1982 (Nest survivorship data are not available) Peak number1 9of83 active nests 0- 500 xxxx 100 1984 100- X 400 1985 200 200- 300 1986 X 1987 500 xxxx 500- 200 1988 X 1000 1989 100 xxxx 1990 X xx 1991 0 1992 xx 1993 xxxx xxxx 1982 1994 xx 1983 1995 x xxxx = no data. 1984 1996 1985 1997 xx xxxx 1986 1998 1987 1999 xx xxxx xx 1988 2000 1989 2001 xx xxxx 1990 2002 1991 2003 xx xxxx 1992 2004 1993 2005 (continued1994 x 1995 = no data. 1996 ) 1997 1998 1999 2000 2001 2002 2003 2004 2005 194 SOUTH SAN FRANCISCO BAY Bair Island North Gr e a t B lue He r on Peak nestling count (colony total) 50 40 (continued) Gr e a t Egr e t 30 20 10 (Nest survivorship data are not available) 0 xxxx xxxx 1982 xxxx Peak number1 9of83 active nests 50 xxxx 1984 xxxx xxxx xxxx 40 1985 1986 30 1987 xxxx 20 1988 xxxx 1989 xxxx 10 1990 xx 0 1991 1992 xx xxxx 1993 xxxx xxxx 1982 1994 xx 1983 1995 x xxxx = no data. 1984 1996 1985 1997 xx xxxx 1986 1998 1987 1999 xx xxxx xx 1988 2000 1989 2001 xx xxxx 1990 2002 1991 2003 xx xxxx 1992 2004 1993 2005 1994 x 1995 = no data. 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 Bair Island South This colony site is on California Department of Fish and Game property 6 km north of Redwood City, adjacent to Redwood Creek, and 1.2 km from San Francisco Bay. Great Blue Herons nested in separate subcolonies on power towers along Redwood Creek and Corkscrew Slough. Great Egrets, Black-crowned Night-Herons, and Snowy Egrets nested in other subcolonies in coyote brush and on the ground. Ownership: public Public observation areas: none Latitude / Longitude: N 37.5263 / W 122.2055 SOUTH SAN FRANCISCO BAY FocalNest survivorship nestBlack-crowned survivorship (± Night- SE) Heron 1.0 0.8 0.6 0.4 0.2 195 Snowy Egret 0 xxxxxxxx xx xx xx xx xx xx xx xx xx xx xx xx xx xx x 1993 xx xx = no data Peak nestling199 count4 (colonyxx xx total) 1995 50 xx xx . Nest survivorship (± SE) 1996 xx xx Focal nest survivorship 1.0 40 1997 xx xx Gr e a t B lue He r on 1998 xx xxxxxx 30 0.8 1999 2000 20 xx xx 0.6 2001 xx xx 10 2002 xx xx 0.4 2003 xx 0.2 Gr e a t Egr e t 0 2004 xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 2005 0 x xxxxxxxx xx xx xx xx xx xx xx xx xx xx xx xx 1991 = no data 1992 xx xx Peak number of active nests x 200 1993 1993 xx xx = no data.