18 September 1982 to 18 March 1983

Waterbird Censuses at Richardson Bay Audubon Sanctuary, 1982 to 2006

Photo by Kerry Wilcox

February 2008

Report to Audubon California and the Richardson Bay Audubon Center and Sanctuary

W. David Shuford PRBO Conservation Science 3820 Cypress Drive # 11 Petaluma, CA 94954 707-781-2555 www.prbo.org

ACKNOWLEDGMENTS The following individuals participated in waterbird censuses at Richardson Bay Audubon Sanctuary and thereby made this report possible: Jean Amidon, Bruce Bajema, Seth Benz, Al Brumter, Carol Farker, Karen Hamblett, Paul Harper, Tony Harrow, Robert Hinz, Toshi Hiraoka, Bob Hogan, John Howard, Ken Howard, Lee Howard, Susana Ives, Richard Jenkins, Anna Kahn, Cindy Kamm, Cindy Lamb, Marti Leland, Bill Lindqvist, Helen Lindqvist, Ricardo Mahler, Maggie Moore, Joe Northrup, Lisa Nostadt, Ed Nute, Marcia Nute, Jolen Osselo, Joel Pagel, Eric Palm, Virginia Plambeck, Lynda Polard, Rachel Pray, Jean Price, Gwen Rino, Clive Saunders, Delanna Schneider, Mike Simms, Hillary Smith, Linda Stevens, Michael Stevenson, Meryl Sundove, Lowell Sykes, Jim White, Karen Wikler, Ricky Ylagan, and several unnamed observers. Thanks also to those who counted birds in the Tiburon subarea of the Marin County (southern) Christmas Bird Count from 1978 to 2005; the subarea data were kindly supplied by Harrison Karr. Bob Hirt and Ed Nute answered questions about coverage boundaries, respectively, for the Strawberry and Tiburon subareas of that CBC. Funding for this report was provided by Audubon California. Gary Langham and Nils Warnock were supportive of this project. Kerry Wilcox kindly provided data from censuses of the Richardson Bay Audubon Sanctuary, maps of the area, the cover photo, and answers to numerous questions relevant to past and current waterbird censuses. Lynne Stenzel provided shorebird data for Richardson Bay from PRBO’s Pacific Flyway Project. Mike Wolder, Joelle Buffa, and Dan Yparraguirre provided perspective on census methods of the midwinter waterfowl surveys of San Francisco Bay. Julie Howar kindly prepared the two maps of the Richardson Bay study area. Jennifer Roth supplied some important references on herring trends in San Francisco Bay. This is Contribution No. 1621 of PRBO Conservation Science.

EXECUTIVE SUMMARY Richardson Bay is recognized as an Important Bird Area in California, yet little prior information has been compiled on the abundance of birds in this bay. A summary of waterbird censuses conducted at the Richardson Bay Audubon Sanctuary irregularly from 1982–83 to 2006–07 and in the Tiburon subarea of the Marin County (southern) Christmas Bird Count (CBC) from 1978 to 2005 documents thousands to tens of thousands of wintering waterbirds in Richardson Bay. Numbers of waterbirds in this bay are typically dominated by a few species or species groups of diving birds, mainly scaup, Ruddy Ducks, large Aechmophorus grebes, Double-crested Cormorants, Buffleheads, and gulls. Numbers of the most numerous waterbirds in the Tiburon subarea of the local CBC were particularly high during the late 1970s and early 1980s, declined in the mid- 1980s, and generally have remained at lower levels since. Although numerous in the late 1970s, American Wigeons, Canvasbacks, and American Coots currently are uncommon to rare in Richardson Bay. Weaknesses in prior census methodology make interpretation of the patterns in waterbird abundance difficult. Still, it appears that fluctuations in numbers of spawning herring and changes in the density and extent of subtidal plants may be the most important local factors influencing waterbird numbers in Richardson Bay in winter. Additionally, wintering numbers of waterbirds on Richardson Bay may be strongly affected by factors elsewhere in their range at other seasons. Trends in waterbird numbers at Richardson Bay vary among species in their consistency with trends at a nearby estuary and at the continental scale. Because movements of waterbirds in and out of the Richardson Bay sanctuary with irregular spawning runs of herring increase the difficulty of interpreting census results, it would be valuable to consider expanding the survey area to include additional portions of Richardson Bay to encompass more of the areas among which birds are moving. Without supplemental surveys to obtain accurate ratios of species within species groups typically lumped on censuses (particularly scaup and Aechmophorus grebes), it will be difficult to track the trends of some of the most numerous species on Richardson Bay if trends for component species differ. Conducting additional opportunistic surveys of key waterbirds species during runs of spawning herring likely would provide insight on the short-term fluctuations of waterbirds in response to these events. It also would be valuable to coordinate monitoring of waterbirds at Richardson Bay with the long-term census programs at Bolinas Lagoon and Tomales Bay on the outer coast of Marin County.

California’s San Francisco Bay estuary is an extremely important area within the Pacific Flyway for migrant and wintering waterfowl, shorebirds, and other waterbirds. Its large size, diverse aquatic habitats, and mild climate make it particularly attractive to these birds despite extensive historic loss and degradation of wetland habitats within the bay. The multiple threats posed by the ongoing activities of the six million people living in proximity to the bay put waterbird populations at risk from contaminants, oil spills, impacts to aquatic food webs from invasive non-native invertebrates and plants, disturbance, lowered water quality, and additional habitat loss and degradation. Planned and ongoing restoration of salt marshes and other wetlands, particularly by conversion of salt ponds in the north and south portions of the bay, may prove beneficial to some species, but the effects of planned restoration remain to be seen. Hence, it will be important to monitor the distribution and abundance of waterbirds in the San Francisco Bay estuary over the long term to assess trends and patterns that my reflect responses to human activities in the bay and to enable remediation of any adverse effects that may occur. Prior research in San Francisco Bay has included comprehensive baywide surveys of waterfowl (Accurso 1992), shorebirds (Stenzel et al. 2002), and some species of rails (Evens et al. 1991, Spautz et al. 2005) and colonial waterbirds (Strong et al. 2004, Kelly et al. 2006). Because of the bay’s large size, most comprehensive surveys have been conducted either infrequently or irregularly. Baywide midwinter waterfowl counts, including waterfowl, American Coots (Fulica americana), and the large Aechmophorus grebes, have been conducted annually in the bay for many years (Joelle Buffa pers. comm.). Baywide shorebird censuses were conducted once during spring and fall migration and twice during winter in the late 1980 and early 1990s, and once in November in 2006 and 2007 (Stenzel et al. 2002, PRBO unpubl. data). Counts of waterbirds have also been conducted in restricted portions or habitats of the bay (e.g., shorebirds, Holway 1990; salt ponds, Warnock et al. 2002) at various intervals and over varying periods of time. Among these are counts of waterbirds conducted irregularly from 1982 to the present within the Richardson Bay Audubon Sanctuary, a portion of that bay in southern Marin County within the larger San Francisco Bay estuary. Although Richardson Bay is recognized as an Important Bird Area in California (Cooper 2004), little information has been compiled on the abundance of birds in this bay. To meet this need, this report summarizes the results of waterbirds censuses at Richardson Bay, describes patterns of waterbird abundance and diversity within the bay, and makes recommendations for continuation and improvement of those surveys.

STUDY AREA Richardson Bay, in southern Marin County, California, is a two-pronged embayment just inside and north of the Golden Gate at the mouth of San Francisco Bay (Figure 1). The narrower and shallower arm, including Bothin Marsh and Pickleweed Inlet, extends northwest to the town of Mill Valley. The Richardson Bay Audubon Sanctuary encompasses about 900 acres of the wider and somewhat deeper northeastern arm of this bay. The sanctuary boundary includes the shoreline of the bay from near the tip of Strawberry Point on the west clockwise north to the head of the bay, south along the Tiburon Peninsula to the vicinity of Belvedere, southwesterly out in open water to its

southern apex, and back northwesterly to Strawberry Point. The sanctuary includes primarily the open waters of inner Richardson Bay and excludes Strawberry Lagoon and Greenwood Cove, connected to the bay on the west, and Belvedere Lagoon, set back from the bay to the southeast. Richardson Bay is relatively shallow and has extensive eelgrass (Zostera marina) beds both within and outside the sanctuary. Spawning runs of Pacific herring (Clupea pallasi) occur in Richardson Bay at irregular intervals in winter, and the large numbers of these fish and the eggs they attach to eelgrass and other subtidal and tidal substrates periodically attract exceptional numbers of waterbirds to this area. The sanctuary’s waters are closed to boats and other watercraft each winter (1 October to 31 March), and, though occasional violations occur, this greatly reduces disturbance to the large numbers of waterbirds that occur at this season.

METHODS The methods described here include those for waterbird censuses of Richardson Bay Audubon Sanctuary organized by sanctuary staff and those for other inventory or monitoring projects if the boundaries of their census areas or subareas coincided closely with those of the sanctuary. The latter includes counts of waterbirds from the Tiburon subarea of the Marin County (southern) Christmas Bird Count (CBC) and counts of shorebirds from PRBO’s Pacific Flyway Project. One monitoring project excluded was the San Francisco Bay component of the midwinter Pacific Flyway waterfowl survey because the Central Bay West subarea encompassing the sanctuary included the more extensive stretch of the bay shoreline from the Richmond–San Rafael Bridge south to the mouth of the Golden Gate (Joelle Buffa pers. comm.). Nomenclature for birds follows the AOU (1998) Check-list of North American Birds and its supplements; scientific names for common names used only in the appendices can be found at www.aou.org/checklist/index.php3.

Richardson Bay Audubon Sanctuary Censuses The periodicity, timing relative to tidal height, census methods, and groups of species counted on censuses of Richardson Bay Audubon Sanctuary have varied considerably over time. Observers conducting censuses from 1982–83 to 1998–98 counted from the east shore of the sanctuary only; for the period 1995–96 to 1998–98, at least, observers counted out in the bay as far as they could see (Ken Howard pers. comm.). Since 2006–07, they have counted from both the east and west shores, and coverage included all of the sanctuary’s shoreline and waters. The observer conducting surveys in 1982–83 used only binoculars, whereas observers on all other counts also used spotting scopes. Observers counted waterfowl, loons, grebes, pelicans and cormorants, and terns in all years, but herons and egrets, shorebirds, and gulls in some but not all years. Censuses in 1982–83. In the 1982–83 season, one observer conducted 16 censuses from 18 September 1982 to 18 March 1983. Census time ranged from 1–1.5 hours, and counts varied both by time of day and tidal height. The observer used 7 x 35 binoculars and counted birds on the periphery of the bay only; thus tides had a substantial influence on results. The observer divided the bay into three “zones” and counted from three

respective vantage points for about 20 minutes each, estimating rafts of birds as a whole rather than counting them individually.

Figure 1. Location of the Richardson Bay Audubon Sanctuary on the San Francisco Bay shoreline of Marin County, California.

Censuses in 1985. In 1985, one observer conducted eight censuses from 15 February to 14 April. The observer counted from four observation points from which collectively the whole bay could be seen: (1) the top of the hill on the sanctuary, from which Pickleweed Island and the freshwater pond beyond was visible, (2) behind the Lyford House, (3) the bench near the start of the bicycle path at Blackie’s Pasture, and (4) the hill beyond the sewer outlet, from which the entire eastern shore could be seen. Counts were always conducted sequentially from points 1 to 4. The observer attempted to “represent all times and tides equally, or at least randomly.” Counts took about three hours at the beginning of the season and less later when there were fewer birds. Censuses in 1987–88. In this season, teams of two to four observers per census conducted a total of eight censuses from 4 November 1987 to 18 March 1988. Observers generally counted from four locations, which apparently correspond to those used in 1985: (1) “back beach back bench top of hill,” (2) Lyford House, (3) Blackie’s Pasture, and (4) bike path. However, counts were not taken at all four spots on all censuses. On the two November census, observers did not count from points 1 and 2 and they did not count gulls at all. On the 18 March census, a count was taken only from point 1. All counts were taken in the morning, apparently without reference to tidal height. Censuses in 1988–89. In this season, two to four observers per census conducted a total of six censuses from 16 December 1988 to 19 March 1989. Observers generally counted from four locations, which apparently correspond to those used in prior years, though counts were not taken from all four points on all censuses. Censuses in 1989–90. In this season, one to three observers per census conducted at least six censuses from 16 November 1989 to 23 January 1990; one census form, apparently from this year, does not include a date. Observers generally counted from four locations, which apparently correspond to those used in prior years, though counts were not taken from all four points on all censuses. Census in 1992. Apparently only one census was conducted this year, on 27 March. Two observers counted from six stations: one on the sanctuary’s back beach, one behind the Lyford House, and four on the trail on the bay’s east shore. Censuses in 1995–96. In this season, one to three observers per census conducted a total of 11 censuses from 17 Oct 1995 to 14 March 1996. Observers counted from four to five of the following stations (Figure 2): (1) back beach of sanctuary, (2) by bench overlooking the bay right after crossing the first bridge along the Tiburon bike path at Blackie’s Pasture, (3) at the gazebo overlooking the bay along bike path, (4) further down the bike path at bench at end of field as path turns sharply back toward Tiburon Blvd., and (5) further on path toward Tiburon at spot past small rocky hill (west side of trail) where there again is a clear view of the bay. Except for an early afternoon count on the single March census, all counts were conducted in morning hours, generally taking 1.5 to 2 hours to complete. Tidal height varied considerably among counts. Observers counted all waterbirds except for herons and egrets and shorebirds. Censuses in 1996–97. In this season, one to four observers per census conducted a total of 10 censuses from 1 November 1996 to 26 March 1997. On each census, observers typically counted from five stations, presumably those described for the 1995–96 season. Counts generally took 1.5 to 2 hours to complete, but start times ranged from 0830 to 1345 hours, apparently because each census period was selected to coincide with the high tide. Observers counted all waterbirds except for herons and egrets and shorebirds.

Censuses in 1997–98. In this season, one to two observers per census conducted a total of 10 censuses from 16 October 1997 to 25 March 1998. On each census, observers counted from five stations, presumably those described for the 1995–96 season. Counts generally took 1.5 hours to complete, but start times ranged from 0835 to 1115 hours, apparently because each census period was selected to coincide with the high tide. Observers counted all waterbirds except for herons and egrets and shorebirds. Censuses in 1998–99. In this season, two to five observers per census conducted a total of 11 censuses from 27 October 1998 to 16 March 1999. On each census, observers counted from five stations, presumably those described for the 1995–96 season. Counts generally took 1.5 to 2 hours to complete, but start times ranged from 0900 to 1400 hours, apparently because each census period was selected to coincide with the high tide. Observers counted all waterbirds except for herons and egrets and shorebirds. Censuses in 2006–07. In this season, four to ten observers per census conducted a total of 8 censuses from 27 October 2006 to 16 March 2007. Start time of the censuses ranged from 0730 to 1200 hours, and they each generally took about 1.5 to 2.5 hours to complete. Censuses generally started at about 2.5–3.5 feet on a rising tide. From five stations (A–D), as described below, observers counted all species of waterbirds on the bay and the few individuals within the Richardson Bay Wildlife Ponds, part of the Richardson Bay Sanitary District facility south of Blackie’s Pasture. For purposes of the census, the sanctuary waters were divided into four zones or subareas (NW, NE, SW, SE; Figure 2), which were counted by a total of five teams. Teams kept in contact, as needed, by handheld two-way radios to avoid double- or undercounting of birds at the boundaries of subareas. The subareas were distinguished by a north-south center line of small yellow buoys and an imaginary east-west line between observation points A on the Strawberry Spit and D about midway along the east shoreline of the bay (west shore of Tiburon Peninsula) between Blackie’s Pasture on the north and the San Rafael Avenue turnoff to Belvedere on the south. One team counted the northwest subarea from census station A on the east side of Strawberry Point (north end Egret Way) just south of the entrance to the boat channel at Strawberry Lagoon opposite the south end of Aramburu Island Preserve. They counted north to the head of the bay, east to the line of yellow buoys, and south to the east-west boundary line. Another team counted the southwest subarea starting at point B along the trail at the end of Heron Drive at the south end of the Strawberry Spit. They counted north to the east- west line, east to the line of yellow buoys, and southeasterly to a line of pilings and canister buoys on the sanctuary’s outer boundary. They first counted most birds in the open water then walked north along the trail to check for shorebirds or other waterbirds that were hugging the immediate shoreline and hence were not visible from the end of the spit. On the east shore, the two subareas were counted by three coordinated teams. One team counted birds in the northeast subarea starting at point C at Blackie’s Pasture then walked south and stopped at intervals to count. They counted north to the head of the bay, west to the line of yellow buoys, and south to where they coordinated counts with team D, which counted from the east-west line north into the northeast subarea to tally birds not visible to team C. Likewise, team D counted from the east-west line south into the southeast subarea to count birds not easily seen by team E, which counted from the Belvedere shoreline (slightly outside the sanctuary boundaries) southwest to the line of

Figure 2. Census zones and stations for waterbird censuses of the Richardson Bay Audubon Sanctuary. Census stations 1–5 used from 1995 to 1999, stations A–E from 2006 to the present (see Methods).

pilings and canister buoys, west to the line of yellow buoys, and north to the area counted by team D.

Marin County (southern) Christmas Bird Count This 15-mi diameter Christmas Bird Count (CBC) has been conducted annually in late December or early January since 1978. The count circle, centered 1.5 mi northwest of Mill Valley, is divided into 23 subareas, and a team of volunteers is assigned to count all birds in each subarea during the same 24-hour period. Data from the Tiburon subarea are included in this report because that area encompasses most of the sanctuary, and waterbirds in Richardson Bay are counted mainly from the Tiburon bike path, which is comparable to the methods used for the sanctuary counts prior to 2006 (see above). Comparison of CBC numbers from the Tiburon subarea with those from sanctuary censuses are somewhat confounded, however, because the Tiburon subarea of the CBC also includes outer Richardson Bay beyond the sanctuary, Raccoon Strait, an additional strip of waters in San Francisco Bay on the east side of the Tiburon Peninsula, plus some adjacent freshwater areas. Details of the methods of the individual counts are not available, but it is probably safe to say that counts have not been consistently coordinated with tidal height.

Pacific Flyway Shorebird Censuses In the late 1980s and early 1990s, PRBO Conservation Science coordinated comprehensive surveys of shorebirds in San Francisco Bay, which included Richardson Bay Audubon Sanctuary, as part of the broader Pacific Flyway Project. This project conducted 10 censuses in the sanctuary from 1988 to 1993: three during fall migration in August or September, one in early winter in November, and six during spring migration in April. Observers counted birds on moderately high rising tides (starting censuses at approximately +0.3 m MLLW at the Golden Gate Bridge; Stenzel et al. 2002).

Summary and Analyses I first consolidated data for all censuses of the Richardson Bay Audubon Sanctuary. Because large numbers of individuals of some species pairs or groups were left unidentified to species on censuses, for the most numerous of these I combined all individuals within each grouping into a single category. Western Grebes (Aechmophorus occidentalis) and Clark’s Grebes (A. clarkia) were combined as Aechmophorus spp., Great Scaup (Aythya marila) and Lesser Scaup (A. affinis) as scaup spp., and all gulls of the genus Larus as gull spp. For purposes of graphing trends in numbers of the most numerous species or groups of waterbirds, I then calculated the mean number of individuals for the winter season in each year, which I defined as the period 15 November to 15 March. The number of censuses taken within this period varied from four to nine among all years. For the data from the Tiburon subarea of the Marin County (southern) CBC, I similarly grouped the same species pairs or species groups into single categories and graphed the single count each year for the most numerous species. In graphing numbers, the year on the x-axis is the first year of the two years spanning the winter season (i.e., 1982 for 1982–83).

Census Limitations All of the surveys have limitations to their use for gauging trends in populations of waterbirds in Richardson Bay. For the Audubon sanctuary, there are count data for only 10 of the 25 years since censuses began in 1982–83, the 10 years are not well distributed over the 25-year period, and there are unequal numbers of censuses and varying census methods among the 10 years. Censuses of waterbirds in the Tiburon subarea of the Marin County (southern) CBC are limited by the lack of rigorous census methodology and the single count each year but have the advantage of a continuous 28-year census record. Difficulties in interpreting trends for both the sanctuary and CBC counts are compounded by the irregular timing of spawning runs of herring in the bay, which can attract large numbers of waterbirds for short time periods that may or may not correspond to the timing of waterbirds censuses in a particular year. Because of the few annual censuses and its relatively short duration, the Pacific Flyway survey is best used in making broad-scale comparisons of the importance to shorebirds of entire sites, such as all of San Francisco Bay, to other such sites or regions during the survey period rather than in assessing long-term trends of shorebird numbers in small portions of much larger sites.

RESULTS Species Richness and Abundance Observers recorded a total of 62 species of waterbirds on censuses of the Richardson Bay Audubon Sanctuary conducted in 10 years from 1982–83 to 2006–07 (Appendices 1–10) and 78 species of waterbirds in the Tiburon subarea of the Marin County (southern) CBC conducted annually from 1978 to 2005 (Appendices 11 and 12). In addition, the Semipalmated Plover (Charadrius semipalmatus) was recorded on a September census of Richardson Bay for the Pacific Flyway Project (Appendix 13) but not on any of the sanctuary or CBC censuses. Phenology of occurrence of key waterbirds varied among years and species, but, overall, highest numbers generally occurred from mid-November to mid-March (Appendices 1–10). Pacific Flyway Project censuses showed peak numbers of shorebirds in fall migration in August and September (Appendix 13), but sanctuary censuses sometimes showed comparable numbers in winter (Appendices 2, 3, 5, 6). Although not truly comparable because of differences in species and areas counted among years, annual peak counts of total waterbirds on censuses of Richardson Bay Audubon Sanctuary in winter (15 Nov–15 Mar) ranged from 2137 to 14,658 (median = 5368). Numbers of waterbirds in Richardson Bay, and vicinity, are typically dominated by a few species or species groups of diving birds (Appendices 1–13). The main ones currently are scaup spp., Ruddy Ducks (Oxyura jamaicensis), large Aechmophorus grebes, Double-crested Cormorants (Phalacrocorax auritus), Buffleheads (Bucephala albeola), and gull spp. Proportional dominance of these species or species groups has varying considerably both within and among years (Appendix 14). Spikes in numbers of these and some other species (e.g., Surf Scoter Melanitta perspicillata) can occur in some years or on particular counts. Species groups typically occurring in low numbers in

Richardson Bay include dabbling ducks, loons, small grebes, herons and egrets, and shorebirds.

Population Trends Numbers of the most numerous waterbirds recorded on the counts of Richardson Bay Audubon Sanctuary varied considerably among census years and showed no compelling long-term trends (Figure 3). By contrast, numbers of the most numerous waterbirds in the Tiburon subarea of the Marin County (southern) CBC were particularly high during the late 1970s and early 1980s, declined in the mid-1980s, and generally remained at lower levels thereafter, with occasional spikes in numbers of some species (Figures 4 and 5). Species or species groups with particularly high CBC numbers in the late 1970s and early 1980s were scaup, Ruddy Duck, Aechmophorus grebes, Surf Scoter, Double-crested Cormorant, American Wigeon (Anas americana), Canvasback (Aythya valisineria), American Coot, and gulls. Correspondence between the counts at the Audubon sanctuary and those on the overlapping CBC subarea were difficult to assess because of the limited number of years with censuses for both, the large gaps between periods of counts at the sanctuary (one of 6 another of 8 years), and the single annual CBC count versus the mean of multiple annual counts at the sanctuary (Figures 3, 4, and 5; see Methods).

DISCUSSION As noted, the value of prior waterbird census data for tracking local population trends in Richardson Bay is compromised because of weaknesses in census methodology compounded by large fluctuations in bird numbers over short periods as they wax and wane in response to irregular spawning runs of herring from November to March. Still, patterns in abundance of herring and other factors might explain some of the trends in waterbird numbers observed at Richardson Bay. Changes in subtidal plant densities and extent may influence bird numbers either directly by limiting a food source for species that consume vegetation or by reducing the substrate for spawning herring and hence the birds that are attracted to eat eggs or adult fish. In addition to, or in combination with, local conditions, wintering numbers of waterbirds on Richardson Bay may be strongly affected by changing conditions elsewhere in their range.

Herring Runs and Subtidal Substrate The frequency and size of spawning runs of herring and the extent of suitable subtidal and tidal substrates for egg attachment are likely important factors explaining fluctuations in numbers of waterbirds using Richardson Bay. Of the waterbirds that currently are, or have been, numerous in Richardson Bay, American Wigeons, Canvasback, scaup, Surf Scoters, Buffleheads, American Coots, and gulls are known to eat the eggs of herring, and large grebes and cormorants are known to consume adult fish (Bayer 1980, references in Kelly and Tappen 1998). California Department of Fish and Game has estimated the size of the adult herring spawning biomass in San Francisco Bay from 1973 to the present (Watters et al.

2004, www.dfg.ca.gov/marine/herring/sf_bay.asp). Richardson Bay, with its dense beds of red algae (Gracilaria spp.), was the primary subtidal spawning area in San Francisco Bay in the 1970s and early 1980s (CDFG 1998). About 84% to 96% of baywide spawning occurred in the north-central bay, including Richardson Bay, from 1978–79 to 1981–82, which was also a period of above average spawning, particularly in 1981–82 (Watters et al. 2004). Hence, the large numbers of diving waterbirds recorded on CBC counts of the Richardson Bay area in the late 1970s to early 1980s (Figures 4 and 5, Appendices 11 and 12) may reflect the large concentrations of spawning herring there at that time. Densities of Gracilaria declined sharply in Richardson Bay in 1982, perhaps in response to storm action during the 1982–83 El Niño, and the proportion of baywide spawning in the Richardson Bay area, though still substantial, remained below historical levels through the early 1990s. Subsequently, densities of Gracilaria and eelgrass have fluctuated, often dramatically, from year to year (CDFG 2006, 2007). The highest historical spawning biomass estimate of herring for San Francisco Bay in 2005–06 was followed by the lowest in 2006–07, the latter an El Niño year (CDFG 2007). The density of Gracilaria, and the extent of area it covered, in Richardson Bay was high in 2005–06, but by 2006–07 the densities of Gracilaria and eelgrass had declined by 99.5% and 43%, respectively, from those in the previous year. Besides the potential effect of storm action on subtidal plants used by spawning herring, densities of eelgrass can be greatly reduced by diving birds (Spratt 1981). Birds my tear off leaves and often pull whole plants out of the substrate, such that by the end of the herring spawning season many lush beds of eelgrass may be cropped to within a few inches of the bottom substate. Because some waterbirds that declined in the Richardson Bay area in the late 1970s to early 1980s, such as American Wigeons and American Coots (Figure 5a), eat large amounts of vegetation, it is possible that declines in subtidal beds of red algae and eelgrass may have forced some of these birds to relocate elsewhere.

Regional and Continental Trends It is also possible, even likely, that some of the trends in waterbird numbers in Richardson Bay reflect broad-scale or continental trends of some species in response to changing conditions elsewhere in their range. Below, comparisons are made of trends in some wintering waterbirds on Richardson Bay to the long-term trends of the continental breeding (and sometimes wintering) populations of waterfowl and other waterbirds. Where appropriate, comparisons are also made to trends for all of San Francisco Bay and to those for Bolinas Lagoon on the outer coast of Marin County, where counts of all waterbirds have been conduced annually in winter from 1972–73 to the present (graphed and described through 2004–05; PRBO unpubl. data at www.prbo.org/cms/366). In response to ongoing siltation, a gradual long-term increase in the extent of the lagoon’s tidal flats and marsh, and a corresponding decrease in open water at lower tides, has possibly had a strong influence on trends in some species of waterbirds at that site. American Wigeon. A decline in numbers of American Wigeon in the Richardson Bay area in the late 1970s and early 1980s, with no subsequent recovery (Figure 5a), does not match local or continental trends in abundance. Estimates of the continental breeding

population of wigeon in the 1970s to mid-1980s hovered around the long-term average (1955–2006), but despite generally lower numbers since they reached the long-term average in the late 1990s and again in 2007 (USFWS 2007). Numbers at Bolinas Lagoon have generally increased since the early 1970s with several peaks and troughs over time (PRBO unpubl. data). Canvasback. Numbers of Canvasback in the Richardson Bay area have paralleled the trend at Bolinas Lagoon, less so the trend in San Francisco Bay, but not at all the continental trend. Estimates of the Canvasback’s continental breeding population were below the long-term (1955–2006) average from the 1980s to mid-1990s but generally have been well above it since then (USFWS 2007). Numbers of Canvasback in San Francisco Bay decreased from about 60,000 individuals in the 1960s to about 25,000 in the early 1990s (Takekawa and Marn 2000). Numbers of Canvasback on the Tiburon subarea of the Marin County (southern) CBC showed a similar decline in the mid-1980s but subsequently did not recover to prior levels (Figure 5a, Appendices 12 and 13). Numbers in that subarea ranged from 410–2026 individuals from 1978 to 1983, 11–83 from 1984 to 1994, and 0–26 from 1995 to 2005. On sanctuary censuses, the mean number of Canvasback on counts from mid-November to mid-March was 118 and 271 individuals in 1982–83 and 1985, respectively; thereafter, none were seen in most years, and the highest count was 16 on a January 2006 census (Appendices 1–10). At Bolinas Lagoon, Canvasback numbers reached a peak of 45 birds in 1977 but declined to 0 by 1992 and remained absent thereafter (PRBO unpubl. data). Greater and Lesser Scaup. Numbers of scaup at Richardson Bay have not closely paralleled trends at the continental scale, though patterns are difficult to interpret because of insufficient information on the proportion of the two species involved. Scaup at Richardson Bay declined sharply from highs in the late 1970s to early 1980s, to reach a lower plateau around which they have fluctuated since (Figure 4a). Continental populations of breeding scaup hovered around the long-term average for 30 years but have been on a steady decline since the mid-1980s (Allen et al. 1999, Afton and Anderson 2001, USFWS 2007). The trend in scaup numbers was stable from 1955 to 1998 in breeding areas believed to contain mostly Greater Scaup, but numbers of Lesser Scaup breeding elsewhere declined an average of 1% per year from 1955 to 1998 (nearly 3% 1988–1998; Allen et al. 1999). Numbers of scaup on midwinter waterfowl surveys of the United States and western Mexico declined significantly from 1955–1997 but not for 1978–1997, as was also the case for just the Pacific Flyway, though apparently this survey is unreliable for assessing the population status of scaup (Afton and Anderson 2001). For the entire Pacific coast, numbers of Greater Scaup declined significantly on CBCs from 1955–1987 and 1955–1995 but not from 1988–1995, whereas Lesser Scaup showed no significant declines for any of these periods (Allen et al. 1999). Surf Scoter. A sharp decline in numbers of Surf Scoters in the Richardson Bay area from the late 1970s to early 1980s, with generally very low numbers since (Figure 4b), does not clearly match local or broad-scale trends in abundance. Numbers of breeding Surf Scoters have declined steadily on surveys in interior Canada and Alaska from 1978– 2002, and winter densities decreased by 57% in Puget Sound from 1978–1979 to 1992– 1999 (Nysewander et al. unpubl. data, www.seaduckjv.org/studies/pro3/pr28.pdf). At Bolinas Lagoon, numbers of Surf Scoters reached a peak (max. about 175) in the late 1970s to

mid-1980s, declined to the mid-1990s, and have been relatively stable at about 50 birds since (PRBO unpubl. data). Bufflehead. Trends of Bufflehead in the Richardson Bay area are unclear. Local CBC data suggest they may have declined somewhat since the late 1970s (Figure 4b), whereas sanctuary counts suggest they may have increased (Figure 3b). Limitations to continental data make comparisons to patterns at Richardson Bay difficult. Gauthier (1993) reported an increase in the continental breeding population from 1955–1992, but recent analyses have included only the eastern population (e.g., USFWS 2007). Number on midwinter waterfowl surveys in the United States also increased from 1955–1979 (Gauthier 1993). Few data are available for the large population breeding in British Columbia and wintering along the Pacific coast. At Bolinas Lagoon, numbers of Bufflehead increased from about 70 birds in 1972 to 270 in 1980, fell to 140 birds in 1987, then increased to about 280 in 2004 (PRBO unpubl. data). Ruddy Duck. The pattern of Ruddy Duck numbers at Richardson Bay declining from highs in the late 1970s to early 1980s (Figure 4a) to reach a lower plateau, around which they have fluctuated since (Figures 3a and 4a), appears to be somewhat consistent with patterns at the local, but not continental, level. The continental breeding population, concentrated in the Prairie-Pothole region, increased from 1955–1998, but there appear to be few reported data for winter or for the West in general (Brua 2002). At Bolinas Lagoon, Ruddy Duck numbers increased from about 400 to 600 from the early 1970s to early 1980s, then declined to about 300 by the mid-1980s and remained relatively stable before declining to about 150 from 2000 to 2004 (PRBO unpubl. data). Western and Clark’s Grebes. A pattern of numbers of large grebes at Richardson Bay declining from highs in the late 1970s to early 1980s (Figure 4a) to reach a lower plateau, around which they have fluctuated since (Figures 3a and 4a), does not appear to be consistent with patterns at the local or continental level. Broad-scale trend data for these grebes are few. Numbers increased surveywide on the North American Breeding Bird Survey from 1966–2006 (Sauer et al. 2006), but this survey is not well suited to sample colonial waterbirds. At Bolinas Lagoon, large grebe numbers increased to about 40 birds in the late 1970s and early 1980s then declined steadily to about 5 individuals in 2004 (PRBO unpubl. data). Double-crested Cormorant. A pattern in the Richardson Bay area of a decline from a peak in the late 1970s and early 1980s to lower numbers since, with occasional spikes (Figure 4b), is not consistent with trends at either the continental or local scale. Since the 1970s, breeding numbers of this species have increased greatly continentwide (Wires and Cuthbert 2006), including on the Pacific coast and in San Francisco Bay (Carter et al. 1995). Numbers of this species in winter on Bolinas Lagoon have generally been increasing in recent years, though except for lows in the early 1970s numbers have ranged from about 30–50 birds (PRBO unpubl. data). American Coot. A pattern of American Coot numbers at Richardson Bay declining from highs in the late 1970s to early 1980s (Figure 5a) to reach a lower plateau around which they have fluctuated since, except for a peak in the late 1990s and early 2000s (Figure 5a, Appendices 1–10), appears to be somewhat consistent with patterns at the local, but not continental, level. Coot numbers surveywide on the North American Breeding Bird Survey were relatively stable from 1966–2006 (Sauer et al. 2006). Numbers

of coots at Bolinas Lagoon increased sharply from about 1000 to over 2000 birds from 1972 to 1976, dropped to <100 by 1979, remained low until increasing to about 700 birds in the mid-1990s, then decreased to 0 in 2004.

Recommendations for Future Work Monitoring strategies are most effective when their goals are clearly defined, data collected are summarized and disseminated promptly, and goals are periodically evaluated and refined as needed. Goals for the sanctuary’s waterbird surveys initiated in 2006 are to better understand the current use of Richardson Bay by waterbird species, compile baseline data for future comparisons, and link analyses to concurrent research on eelgrass and oysters (www.tiburonaudubon.org/conserve_bay.html#waterbirds). In addition, a separate protocol is being developed with staff from U.S. Geological Survey in Vallejo for finer-scale analysis of the relationships between birds and the bay habitat. The standardization of the waterbird survey protocol in 2006 to use distinct landmarks for boundaries of four census subareas, to count from both sides of the bay to ensure coverage of all waters and shoreline in the sanctuary, and to conduct all censuses at a similar tidal height are substantial improvements over prior survey methods. Suggestions for minor improvements to current methodology are to incorporate Strawberry Lagoon, Greenwood Cove, and Belvedere Lagoon as part of the survey area even though they are outside the sanctuary’s boundaries. The former two areas are directly connected to the inner part of the sanctuary, and surely birds move between these areas and the adjacent northwestern census subarea. This would also ensure coverage of the salt marshes in Greenwood Cove, including both islands in that cove and the shoreline marsh west of the creek north of Harbor Cove Way. Coverage of these areas would require little additional effort and could be done on each census after the completion of counts in the main nearby subareas. Offsetting issues of bird movement. As noted previously, the patterns of waterbird use in the sanctuary appear to be strongly influenced by the response of birds to irregular runs of Pacific herring. This can confound the results of regular waterbird censuses scheduled to specific calendar dates that may or may not coincide with the timing of herring runs. Studies of Harlequin Duck (Histrionicus histrionicus) aggregations at herring spawning events in British Columbia show that birds can shift considerable distances to exploit these rich but temporarily available food resources (Rodway et al. 2003). The percentage of these ducks moving to herring spawning locations was inversely related to the distance they had to travel. Although marked ducks rarely traveled more than 80 km, apparently relatively large numbers moved up to 40 km to take advantage of herring spawning. Thus, it is likely that large numbers of waterbirds from elsewhere in San Francisco Bay, including the outer portions of Richardson Bay, are shifting to the sanctuary during periods of herring spawning. Because the sanctuary is in a sheltered embayment of inner Richardson Bay, it is also likely that some waterbirds move there to roost during periods of stormy weather or after foraging at nearby herring spawning events, which in many years are concentrated around the tip of the Tiburon Peninsula, Angel Island, and the shoreline from Sausalito to the Golden Gate (maps in Spratt 1981). One possible way to offset the issue of bird movement would be to expand the survey area to include the outer portions of Richardson Bay and the westerly embayment

extending north to Mill Valley, hence encompassing more of the areas among which birds are moving. The outer boundaries of an expanded survey area might include Raccoon Strait (including Kiel, Lyford, and Belvedere coves and the shoreline of Angel Island) and open bay waters from Angel Island westerly to Sausalito and/or Fort Baker. Such an expansion would require the use of observers on two to three boats working in coordination, as has been done successfully on Tomales Bay on the outer Marin coast (Kelly and Tappen 1998, John Kelly pers. comm.). These boats could also cover navigable inner portions of both embayments of Richardson Bay. Tallying bird numbers within various subareas, both current ones and new ones in the expanded area, would allow comparisons of the proportion of birds in various portions of the bay and how these vary in relation to storm activity and herring spawning. Some ground counts would still need to be incorporated, as is done around Tomales Bay immediately prior to the boat counts. This would be particularly the case if the embayment of Pickleweed Inlet and Bothin Marsh were included. To facilitate an expanded survey, it might be valuable to partner with the Marin Audubon chapter, to increase participation, and to conduct fewer surveys to limit overall personnel requirements. To set a minimum number of surveys, it would be valuable to consult with Gary Page and Lynne Stenzel at PRBO, for Bolinas Lagoon, and John Kelly at Audubon Canyon Ranch, for Tomales Bay, to see what number of censuses they consider a reasonable balance between adequately assessing winter numbers and maintaining enough people to conduct surveys over the long term. Data summary and dissemination. Despite recent improvements in survey methodology and prompt data entry after surveys, summaries of the results of individual waterbird surveys apparently are not compiled and disseminated in a timely manner. In addition to counting the numbers of each species, observers on waterbird censuses are asked to record data on the age and sex of birds, if known, and their behavior. Collection of these latter data might better be done as part of the finer-scale work being conducted by the U.S. Geological Survey. Currently this makes additional demands on censusers that may compromise the accuracy of overall counts of numbers, and the accessory data may not prove valuable unless they are being gathered for a particular purpose that is supported by a specific study design and a careful evaluation of the type of analyses needed to answer particular questions. Simplifying data collection for the coarse-scale waterbird censuses would also allow for more rapid summary and dissemination of results. If just numbers of species of waterbirds were tallied, each of the four census teams could submit totals for all species in their subarea on a single census form. This would enable data entry just by species and subarea and easy summary of totals for all species for the entire census area. Seeing the results of their work is a strong motivation for long-term involvement of volunteers. If data collection and entry were relatively easy, this would allow the summary of census results shortly after each census and their posting to the sanctuary’s website, where they could be easily viewed by volunteers and other interested parties. Currently there appears to be a long lag between the collection of waterbird census data and posting of summaries to the sanctuary website. It might be valuable to post the data for individual censuses broken down by the four census subareas, as volunteers may be particularly interested in how results from their census area compare to the whole, and

distribution patterns may be revealed at the subarea level that are not evident from sanctuary totals. Supplemental surveys. It would be valuable to conduct supplemental surveys to provide better information on the ratios of species within species groups that are both numerous on Richardson Bay and hard to distinguish without careful scrutiny. In particular, it would be valuable to obtain more accurate information on the ratios of Western Grebes to Clark’s Grebes and Lesser Scaup to Greater Scaup, which are mostly lumped on censuses, respectively, as Aechmophorus spp. and scaup spp. Specific surveys to obtain such ratios would need to be conducted by skilled observers with the ability to identify the species in question at long distances. Although ratios can be obtained by taking multiple samples, it would be important to sample birds at varying distances from shore to ensure that there is no bias introduced if species segregate by water depth or distance from shore, as has been reported for Western and Clark’s grebes (Nuechterlein 1981, Nuechterlein and Buitron 1989). It is possible that some species may segregate by salinity gradients or bottom substrates. If ground-based surveys proved ineffective, it would be necessary to conduct boat surveys to aid in identity of birds far from shore. Regardless of the method used, it would be best to conduct surveys for species ratios as close as possible to the time of the overall waterbirds censuses so that the ratios can be reasonably applied to the census totals to estimate the overall numbers of the species involved. Because spawning runs of herring may have a large influence on the number of waterbirds in Richardson Bay, it would be worth considering conducting supplemental surveys to evaluate the extent of such effects. Surveys could be conducted opportunistically when herring are running, and counts could focus on the most numerous waterbirds species that are known to eat adult herring or their eggs. It would be valuable to conduct counts during periods when herring are spawning both within and outside the sanctuary, as numbers of waterbirds in the sanctuary may increase greatly both by the presence of foraging birds but perhaps also by birds moving to roost in the sanctuary after foraging in outer Richardson Bay or adjacent San Francisco Bay. To enhance the interpretation of results of surveys of waterbirds during herring spawning events, it would be valuable to coordinate with California Department of Fish and Game to obtain data they collect both on the timing and abundance of annual spawning and on densities and extent of subtidal plants used as spawning substrate. Coordination of surveys. Currently there are very few long-term census programs for waterbirds in California. Two of these are being conducted at estuaries on the outer coast of Marin County at Bolinas Lagoon by PRBO and at Tomales Bay by Audubon Canyon Ranch. If they have not already done so, it would be valuable if sanctuary staff consulted with the coordinators of these other long-term census projects to consider coordination of census frequency and timing among these sites and Richardson Bay and to share insights in census methods or analyses of results. The North American Waterbird Conservation Plan calls for development of a set of standardized waterbird monitoring methods for both populations and habitats at multiple geographic and temporal scales. Although a draft manual is available on techniques for monitoring breeding seabirds and colonial waterbirds (www.pwrc.usgs.gov/cwb/manual/), there does not yet appear to be any national

standards or recommendations for monitoring wintering populations of waterbirds or any continental program to coordinate counts at local sites to enable broadscale monitoring of waterbirds. It would be valuable for sanctuary staff to stay abreast of developments in this arena and to contribute to a regional or national monitoring program when one is put in place.

LITERATURE CITED Accurso, L. M. 1992. Distribution and abundance of wintering waterfowl on San Francisco Bay, 1988–1990. Unpublished Master’s thesis, Humboldt State University, Arcata, CA.

Afton, A. D., and M. G. Anderson. 2001. Declining scaup populations: A retrospective analysis of long-term population and harvest survey data. Journal Wildlife Management 65:781–796.

Allen, G. T., D. F. Caithamer, and M. Otto. 1999. A review of the status of Greater and Lesser scaup in North America. U. S. Fish and Wildlife Service, Office of Migratory Bird Management, 4401 North Fairfax Dr., Suite 634, Arlington, VA 22203–1610. Available at www.fws.gov/migratorybirds/reports/scaup/scaup.pdf.

American Ornithologists’ Union (AOU). 1998. Check-list of North American Birds, 7th ed. Am. Ornithol. Union, Washington, DC.

Bayer, R. D. 1980. Birds feeding on herring eggs at the Yaquina estuary, Oregon. Condor 82: 193–198.

Brua, R. B. 2002. Ruddy Duck (Oxyura jamaicensis), in The Birds of North America Online (A. Poole, ed.). (http://bna.birds.cornell.edu/bna/species/696).

California Department of Fish and Game. 1998. Final Environmental Document, Pacific herring commercial fishing regulations (Sections 163, 163.5, 164, Title 14, California Code of Regulations). Chapter 5. Cumulative effects. Calif. Dept. Fish Game, Sacramento. Available at www.dfg.ca.gov/marine/herring/ceqa.asp.

California Department of Fish and Game. 2006. Final Supplemental Environmental Document, Pacific herring commercial fishing regulations (Sections 163, 163.5, 164, Title 14, California Code of Regulations). Chapter 3. Environmental setting. Calif. Dept. Fish Game, Sacramento. Available at www.dfg.ca.gov/marine/herring/ceqa.asp.

California Department of Fish and Game. 2007. Final Supplemental Environmental Document, Pacific herring commercial fishing regulations (Sections 163, 163.1, 163.5, 164, Title 14, California Code of Regulations). 3. Environmental setting. Calif. Dept. Fish Game, Sacramento. Available at www.dfg.ca.gov/marine/herring/ceqa.asp.

Carter, H. C., A. L. Sowls, M. S. Rodway, U. W. Wilson, R. W. Lowe, G. J. McChesney, F. Gress, and D. W. Anderson. 1995. Population size, trends, and conservation problems of the Double-crested Cormorant on the Pacific coast of North America. Colonial Waterbirds 18 (Special Publication 1): 189–215.

Cooper, D. S. 2004. Important Bird Areas of California. Audubon California, Pasadena.

Evens, J. G., G. W. Page, S. A. Laymon, and R. W. Stallcup. 1991. Distribution, relative abundance, and status of the California Black Rail in western North America. Condor 93:952–966

Gauthier, G. 1993. Bufflehead (Bucephala albeola), in The Birds of North America Online (A. Poole, ed.). (http://bna.birds.cornell.edu/bna/species/067).

Holway, D. A. 1990. Patterns of winter shorebird occurrence in a San Francisco Bay marsh. Western Birds 21:51–64.

Kelly, J. P., K. Etienne, C. Strong, M. McCaustland, and M. Parkes. 2006. Annotated atlas and implications for the conservation of heron and egret nesting colonies in the San Francisco Bay area. ACR Tech. Rep. 90-3-17. Available from Audubon Canyon Ranch, 4990 Shoreline Hwy. 1, Stinson Beach, CA 94970 or at www.egret.org/atlas.html.

Kelly, J. P., and S. L. Tappen. 1998. Distribution, abundance, and implications for conservation of winter waterbirds on Tomales Bay, California. Western Birds 29:103–120.

Nuechterlein, G. L. 1981. Courtship behavior and reproductive isolation between Western Grebe color morphs. Auk 98:335–349.

Nuechterlein, G. L., and D. P. Buitron. 1989. Diving differences between Western and Clark’s grebes. Auk 106:467–470.

Rodway, M. S., H. M. Regehr, J. Ashley, P. V. Clarkson, R. I. Goudie, D. E. Hay, C. M. Smith, and K. G. Wright. 2003. Aggregative response of Harlequin Ducks to herring spawning in the Strait of Georgia, British Columbia. Canadian Journal Zoology 81:504–514.

Sauer, J. R., J. E. Hines, and J. Fallon. 2006. The North American Breeding Bird Survey, results and analysis 1966–2006, version 6.2.2006. USGS Patuxent Wildlife Research Center, Laurel, MD (www.mbr-pwrc.usgs.gov/bbs/).

Spautz, H., N. Nur, and D. Stralberg. 2005. California Black Rail (Laterallus jamaicensis coturniculus) distribution and abundance in relation to habitat and landscape

features in the San Francisco Bay estuary. USDA Forest Serv. Gen. Tech. Rep. PSW-GTR-191.

Spratt, J. D. 1981. Status of the Pacific herring, Clupea harengus pallasii, resource in California, 1972 to 1980. Calif. Dept. Fish and Game Fish Bulletin 171.

Stenzel, L. E., C. M. Hickey, J. E. Kjelmyr, and G. W. Page. 2002. Abundance and distributio n of s horebirds in the San Franc isco Bay area. Western Birds 33 :69–98.

Strong, C. M., L. B. Spear, T. P. Ryan, and R. E. Dakin. 2004. Forster’s Tern, Caspian Tern, and California Gull colonies in San Francisco Bay: Habitat use, numbers and trends, 1982–2003. Waterbirds 27:411–423.

Takekawa, J. Y., and C. M. Marn. 2000. Canvasback (Aythya valisineria), in Goals Project. Baylands ecosystem species and community profiles: Life histories and environm ental requireme nts of key plants, fish, and wildlife (P. R. Olofson, ed.), pp. 268–273. Prepared by the San Francisco Bay Area Wetlands Ecosystem Goals Project. San Francisco Bay Regional Water Quality Control Board, Oakland, CA.

U.S. F ish and Wildlife Service. 2007. Waterfowl population status, 2007. U.S. Department of the Inter ior, W ashington, DC. Available at http://www.fws.gov/migratorybirds/reports/reports.html.

Warn ock, N., G . W. Page, M. Ruhlen, N. Nur, J. Y. Takekawa, and J. T. Hanson. 2002. Management and conservation of San Francisco Bay salt ponds: Effects of pond salinity, area, tide, and season on Pacific Flyway waterbirds. Waterbirds 25 (Special Publication 2): 79–92.

Watters, D. L., H. M. B rown, F. J. Griffin, E. J. L arson, a nd G. N. Cherr. 2004. Pa cific herring spawning grounds in San Francisco Bay: 1973–2000, in Early life history of fishes in the San Francisco estuary and watershed (F. Feyrer, L. R. Brown, R. L. Brown, and J. J. Orsi, eds.), pp. 3–14. American Fisheries Society Symposium 39.

Wires , L. R., and F. J. Cuthbert. 2006. Historic populations of the Double-crested Cormorant (Phalacrocorax auritus): Implications for conservation and management in the 21st century. Waterbirds 29:9–37.

Appendix 1. Numbers of waterbirds on censuses of Richardson Bay Audubon Sanctuary, 1982–83

Species 18 Sep 7 Oct 15 Oct 29 Oct 4 Nov 14 Nov 17 Nov 10 Dec 21 Dec 31 Dec 7 Jan 14 Jan 18 Feb 27 Feb 4 Mar 18 Mar

Northern Pintail 10 0 2 0 0 3 0 0 0 6 0 3 0 8 0 0 Canvasback 17 13 80 165 111 180 115 139 126 172 158 72 134 72 77 64 scaup spp. 1602 2400 2200 2200 2500 2880 1811 2505 2687 2550 2330 1900 2450 1575 1170 735 Surf Scoter 3 18 166 492 43 85 83 159 91 60 350 156 54 53 0 6 White-winged Scoter 1 0 0 3 0 4 0 0 8 0 25 3 0 12 0 1 Bufflehead 0 1 0 3 10 17 0 13 19 25 12 7 13 18 11 13 Common Goldeneye 0 0 0 0 3 1 0 6 11 3 13 0 3 1 0 2 Barrow's Goldeneye 0 0 0 0 0 0 0 0 1 0 2 0 0 3 0 0 Red-breasted Merganser 0 0 0 3 2 3 0 1 0 1 1 5 0 1 3 2 Ruddy Duck 205 702 905 466 1600 1915 1970 1953 1385 2176 2165 2460 2100 1328 1021 202 Red-throated Loon 0 0 0 0 0 0 3 2 1 2 1 0 6 1 0 1 Pacific Loon 0 0 0 1 0 1 0 1 0 0 2 1 0 1 0 0 Common Loon 0 0 0 0 0 0 1 0 1 0 0 0 0 1 0 0 Pied-billed Grebe 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 Horned Grebe 13 0 0 0 0 0 0 1 7 3 3 6 3 3 1 4 Eared Grebe 0 0 0 0 0 0 0 0 1 0 40 0 0 1 0 0 Aechmophorus spp. 257 51 106 220 68 60 115 62 24 28 2 29 48 82 19 51 Brown Pelican 2 6 3 0 1 0 3 3 0 1 0 0 0 0 0 31 Brandt's Cormorant 2 0 0 0 0 0 0 5 0 0 1 0 0 0 0 1 Double-crested Cormorant 457 53 198 666 38 35 17 355 602 19 68 469 6 50 62 0 Great Blue Heron 2 1 0 1 0 1 2 2 1 0 3 1 1 1 1 1 Great Egret 1 3 2 0 2 2 1 1 2 0 2 0 0 3 1 2 Snowy Egret 2 3 6 0 3 1 5 3 3 3 1 3 2 2 1 0 Black-crowned Night-Heron 0 1 0 0 1 0 0 3 0 1 1 0 0 0 0 1 American Coot 18 0 0 3 0 13 1 11 13 6 14 9 8 2 1 3 Black-bellied Plover 6 3 3 0 1 7 2 3 1 2 6 3 3 0 1 7 Killdeer 2 1 7 0 2 6 0 0 1 3 3 1 0 6 1 2 American Avocet 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 Greater Yellowlegs 0 0 0 0 0 0 0 1 0 0 0 0 1 0 0 0 Willet 26 13 25 0 22 21 4 19 24 23 24 6 13 25 6 0 Spotted Sandpiper 2 6 1 5 4 1 3 1 1 1 3 0 2 0 1 1 Long-billed Curlew 0 2 1 0 0 0 0 0 0 0 0 0 0 1 0 0 Marbled Godwit 0 0 2 0 0 0 0 0 0 2 0 0 0 3 0 0

Appendix 1 (continued)

Species 18 Sep 7 Oct 15 Oct 29 Oct 4 Nov 14 Nov 17 Nov 10 Dec 21 Dec 31 Dec 7 Jan 14 Jan 18 Feb 27 Feb 4 Mar 18 Mar

Black Turnstone 10 0 17 1 0 0 0 0 0 0 12 5 6 0 0 0 Western Sandpiper 3 17 2 0 0 6 0 0 0 0 19 1 11 59 0 0 Least Sandpiper 150 152 81 0 23 30 12 0 0 19 55 0 0 11 0 0 Dunlin 1 0 4 0 1 2 0 0 0 0 3 4 0 5 0 0 dowitcher spp. 0 0 0 18 0 0 0 0 0 0 0 0 0 0 0 0 Heermann's Gull 0 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 Mew Gull 12 0 7 0 11 7 0 1 0 0 0 3 0 1 0 1 Ring-billed Gull 137 100 32 18 25 58 59 0 18 11 51 17 28 33 19 1 California Gull 1 3 1 0 2 34 50 5 0 0 5 48 11 1 7 11 Western Gull 82 6 128 205 27 38 158 32 90 15 75 33 37 46 44 0 Glaucous-winged Gull 0 0 0 60 6 2 7 2 18 12 16 3 0 13 3 40 Caspian Tern 5 12 7 0 0 0 0 0 0 0 0 0 0 0 0 0 Elegant Tern 6 26 4 6 8 2 0 0 0 0 0 0 0 0 0 0 Forster's Tern 2 23 17 12 1 10 1 13 3 12 8 5 7 0 4 10 Common Murre 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0

Totals 3037 3616 4008 4548 4515 5425 4425 5302 5141 5156 5474 5253 4948 3423 2454 1193

Appendix 2. Numbers of waterbirds on censuses o f Richardso n Bay Audubon Sanctuary, 1985.

15 Feb 20 Feb 28 Feb 8 Mar 22 Mar 29 Mar 7 Apr 14 Apr

American Wigeon 14 2 12 0 6 0 4 0 Mallard 0 0 14 6 8 8 0 6 Cinnamon Teal 0 0 4 4 4 4 8 4 Northern Pintail 27 17 10 26 16 14 12 8 Canvasback 420 204 185 276 178 143 0 0 scaup spp. 376 1016 1456 1130 1145 1115 218 20 Surf Scoter 6 3 1 14 10 0 7 1 White-winged Scoter 0 1 0 0 1 0 0 0 Bufflehead 12 67 64 74 240 114 8 10 Red-breasted Merganser 0 1 1 1 0 0 2 2 Ruddy Duck 5100 2838 2610 3420 2660 2240 473 13 Pacific Loon 0 1 0 0 0 0 0 0 Common Loon 0 3 0 1 2 0 0 0 Pied-billed Grebe 0 1 1 0 0 0 0 0 Horned Grebe 0 9 4 4 0 0 0 0 Eared Grebe 20 1 0 0 10 4 2 0 Aechmophorus spp. 3300 2106 1534 1348 720 480 19 5 Double-crested Cormorant 10 39 65 44 45 51 19 100 Great Blue Heron 2 4 0 2 1 1 1 2 Great Egret 3 2 2 2 2 3 3 0 Snowy Egret 1 2 8 11 6 10 5 6 American Coot 10 58 22 74 72 52 22 26 Black-bellied Plover 0 1 6 8 8 3 6 9 Killdeer 8 6 6 4 2 0 2 0 Greater Yellowlegs 0 0 0 0 1 0 0 0 Willet 68 57 76 81 74 80 62 46 Spotted Sandpiper 0 0 3 1 1 2 0 0 Whimbrel 0 0 0 0 0 0 0 2 Long-billed Curlew 2 0 2 1 1 1 1 1 Marbled Godwit 0 0 0 1 1 0 0 0 Sanderling 145 0 0 40 0 0 0 0 Least Sandpiper 40 0 0 0 0 0 0 0 dowitcher spp. 0 0 0 0 0 0 26 36 gull spp. 180 – 640 85 0 498 87 60 Forster's Tern 9 9 4 0 2 18 14 8

Totals 9573 6449 6710 6658 5116 4841 1001 365

Appendix 3. Numbers of waterbirds on censuses of Richardson Bay Audubon Sanctuary, 1987–88.

4 Nov 20 Nov 10 Dec 5 Feb 12 Feb 4 Mar 11 Mar 18 Mar

Canada Goseo 0 0 0 0 0 1 0 0 American Wigeon 0 0 3 0 0 0 0 0 Mallard 0 4 2 2 4 4 8 6 Cinnamon Teal 0 0 0 3 0 0 0 0 Northern Pintail 0 0 0 5 3 7 5 0 scaup spp. 360 352 360 1790 555 1180 629 90 Surf Scoter 45 218 16 0 0 14 6 0 Bufflehead 18 0 3 5 9 22 12 6 Common Goldeneye 0 5 0 0 0 0 0 2 Red-breasted Merganser 0 0 0 1 0 0 0 0 Ruddy Duck 302 104 296 1200 1500 180 400 0 Common Loon 1 0 0 0 0 0 0 0 Pied-billed Grebe 2 0 0 0 0 0 0 0 Horned Grebe 0 1 0 0 0 1 5 2 Eared Grebe 10 0 0 30 1 1 0 0 Western Grebe 240 229 473 500 700 456 200 0 Clark's Grebe 5 0 1 0 0 0 0 2 Brown Pelican 6 1 4 1 0 0 0 0 Double-crested Cormorant 10 2 11 13 14 11 17 4 Great Blue Heron 0 0 1 2 3 0 7 3 Great Egret 1 0 4 0 1 2 1 2 Snowy Egret 0 1 4 0 2 0 2 5 Black-crowned Nigh t-Heron 0 0 2 1 1 1 1 0 American Coot 12 21 6 11 13 0 12 0 Black-bellied Plover 2 2 5 5 4 4 3 3 Willet 3 2 3 24 33 17 40 15 Spotted Srandpipe 2 0 1 0 0 1 0 0 Long-billed Curlew 0 0 0 1 1 0 3 0 Sanderling 0 0 23 0 0 6 0 0 Western Sandpiper 0 15 0 121 86 0 0 6 Dunlin 0 0 0 1 0 0 0 0 peep sp. 0 0 10 0 0 0 0 0 Ring-billed Gull 0 0 45 0 0 0 0 0 California Gull 0 0 14 0 0 0 0 0 Thayer's Gull 0 0 3 0 0 0 0 0 gull spp. – – 50 135 175 38 0 0 Caspian Tern 0 0 0 0 0 0 0 1 Forster's Tern 0 0 2 0 3 0 13 1

Totals 1019 957 1342 3851 3108 1945 1364 148

Appendix 4. Numbers of waterbirds on censuses of Richardson Bay Audubon Sanctuary, 1988–89.

16 Dec 11 Jan 8 Feb 22 Feb 13 Mar 19 Mar

Mallard 2 0 0 0 6 2 scaup spp . 517 622 271 5 302 125 Surf Scoter 738 0 0 0 0 2 White-winged Scoter 65 0 0 0 0 0 Bufflehead 5 0 0 0 0 0 Ruddy Duck 438 647 908 0 0 0 Western Grebe 0 0 108 0 0 0 grebe spp. 237 152 0 60 0 3 Brown Pelican 0 0 0 0 0 1 Double-crested Cormorant 2 0 0 1 1 0 American Coot 0 0 8 0 0 7 Black-bellied Plover 8 2 0 1 0 0 Willet 7 13 1 3 11 0 Spotted Sandpiper 0 0 3 0 0 0 Long-billed Curlew 1 0 0 0 1 0 Marbled Godwit 3 2 0 0 0 0 Black Turnstone 4 45 0 0 0 0 Sanderling 0 2 0 0 0 0 Least Sandpiper 2 0 0 0 0 0 Dunlin 0 0 0 0 0 1 peep sp. 0 30 0 90 0 0 gull spp. 108 220 50 60 119 0 Forster's Tern 0 18 0 0 0 0

Totals 2137 1753 1349 220 440 141

Appendix 5. Numbers of waterbirds on censuses of Richardson Bay Audubon Sanctuary, 1989–90.

16 Nov 23 Nov 30 Nov 7 Dec 14 Dec 23 Jan

American Wigeon 0 3 0 0 0 0 Mallard 0 0 0 20 0 1 Canvasback 0 0 3 1 0 0 scaup spp. 2 37 30 777 422 600 Surf Scoter 0 1 85 0 1 3 Bufflehead 140 32 516 680 220 12 Common Gold eneye 39 0 158 66 1 0 Barrow's Goldeneye 0 0 0 3 0 0 Red-breasted Merganser 21 0 12 4 9 0 Ruddy Duck 860 367 1071 1009 1291 571 Red-throa ted Loon 1 0 3 0 1 0 Pied-billed Grebe 0 2 0 0 0 0 Horned Grebe 1 0 1 1 0 0 Eared Grebe 21 13 3 3 4 0 Western G rebe 343 4 76 249 601 318 150 Clark's Grebe 0 4 0 4 0 0 Brown Pelican 2 0 0 0 0 0 Double-crested Cormorant 770 700 265 0 0 3 Snowy Egret 1 0 0 0 0 0 American Coot 5 0 8 2 0 0 Black-bellied Plover 1 2 1 1 0 2 Killdeer 3 6 0 0 0 0 Greater Y ellow legs 0 0 0 0 0 0 Willet 1 3 0 0 0 5 Long-billed Curlew 0 0 0 0 0 2 Black Turnstone 0 0 20 9 0 0 Sanderling 4 0 0 0 0 8 Western Sandpiper 0 0 0 0 0 200 Dunlin 0 0 0 0 0 100 peep sp. 240 480 290 800 0 125 gull sp p. 196 0 0 0 0 18 Forster's Tern 0 0 0 0 0 1

Totals 2651 2126 2715 3981 2267 1801

Appendix 6. Numbers of waterbirds on censuses of Richardson Bay Audubon Sanctuary, 1995–96.

17 Oct 31 Oct 7 Nov 28 Nov 5 Dec 22 Dec 2 Jan 23 Jan 6 Feb 22 Feb 14 Mar

Mallard 5 10 17 3 0 0 4 0 0 0 2 scaup spp. 16 0 240 584 1191 367 8345 1203 4200 818 485 Surf Scoter 8 0 18 6 0 0 0 0 41 4 0 Bufflehead 0 224 54 93 222 9 38 50 20 111 0 Common Goldeneye 0 0 0 3 0 0 15 0 0 0 0 Red-breasted Merganser 0 0 0 1 0 0 0 2 0 4 7 Ruddy Duck 431 1780 2000 1820 2415 855 2733 670 3588 858 640 Red-throated Loon 0 0 0 0 0 0 1 0 0 11 0 Pacific Loon 0 0 0 0 0 0 0 0 0 3 0 Common Loon 0 0 0 0 0 0 1 1 0 4 0 loon spp. 0 0 0 0 0 0 0 0 0 22 0 Pied-billed Grebe 6 0 1 0 0 0 0 0 0 0 0 Horned Grebe 0 0 2 1 4 0 6 0 0 0 2 Eared Grebe 0 1 0 1 0 0 0 0 0 3 3 Western Grebe 201 0 0 0 0 12 0 0 0 0 0 Clark’s Grebe 5 1 0 0 0 0 0 0 0 0 0 Aechmophorus spp. 0 162 430 523 1390 548 264 757 428 2010 1508 grebe spp. 36 0 0 0 0 0 0 0 0 0 0 Brown Pelican 5 0 12 6 1 0 7 0 0 0 0 Double-crested Cormorant 521 87 25 154 208 0 83 0 10 21 0 Great Blue Heron 2 0 0 2 1 0 0 0 1 1 0 Great Egret 2 0 1 0 1 0 0 2 1 0 3 Snowy Egret 4 0 0 1 0 0 0 0 1 3 3 Black-crowned Night-Heron 0 0 0 0 0 0 0 1 0 0 0 American Coot 79 50 83 25 41 13 16 6 0 0 0 Black-bellied Plover 1 4 5 12 0 1 6 4 1 3 3 Killdeer 0 2 0 0 0 0 0 0 2 0 0 Greater Yellowlegs 1 0 0 1 0 0 0 0 0 0 1 Willet 22 11 12 36 2 8 7 19 3 63 16 Spotted Sandpiper 0 1 1 1 1 2 0 1 1 0 0 Long-billed Curlew 0 1 0 0 0 0 0 0 0 0 4 Marbled Godwit 1 0 0 2 0 0 0 0 0 0 5 Black Turnstone 0 7 0 0 0 0 0 28 0 0 1 Sanderling 0 0 0 3 0 72 7 69 75 32 3

Appendix 6 (continued)

17 Oct 31 Oct 7 Nov 28 Nov 5 Dec 22 Dec 2 Jan 23 Jan 6 Feb 22 Feb 14 Mar

Western Sandpiper 0 0 0 0 0 0 0 38 0 12 0 Least Sandpiper 23 0 0 55 0 109 0 0 0 0 0 Dunlin 0 0 0 140 2 26 75 0 0 0 0 peep sp. 35 0 80 0 7 0 0 145 0 600 0 Mew Gull 0 0 0 0 0 0 0 2 0 0 0 Ring-billed Gull 0 26 17 7 0 16 0 83 83 11 48 California Gull 0 10 0 0 0 6 0 30 35 0 0 Western Gull 2 6 2 36 2 2 33 3 30 7 20 Glaucous-winged Gull 0 0 0 0 0 1 17 2 2 1 0 gull spp. 5 23 8 145 11 0 3000 0 14 159 19 Elegant Tern 0 10 0 0 0 0 0 0 0 0 0 Forster’s Tern 5 7 16 10 0 7 0 0 0 15 32 Common Murre 0 0 0 0 1 0 0 0 0 0 0

Totals 1416 2423 3024 3671 5500 2054 14658 3116 8536 4776 2805

Appendix 7. Numbers of waterbirds on censuses of Richardson Bay Audubon Sanctuary, 1996–97.

1 Nov 12 Nov 26 Nov 10 Dec 7 Jan 21 Jan 4 Feb 18 Feb 12 Mar 26 Mar

Mallard 0 0 0 0 0 0 0 2 0 0 Greater Scaup 0 0 0 0 16 0 34 43 0 0 scaup spp. 0 348 2084 381 730 336 203 494 1224 746 Surf Scoter 56 1 46 45 1 12 6 12 13 17 Bufflehead 160 250 428 568 156 15 186 140 0 0 Common Goldeneye 47 7 0 1 0 0 4 0 0 0 Red-breasted Merganser 9 0 0 0 0 0 0 6 0 6 Ruddy Duck 349 1815 820 624 2094 206 182 508 363 134 Red-throated Loon 0 0 0 0 0 0 1 0 8 0 Common Loon 0 0 0 0 0 0 1 2 11 0 loon spp. 0 0 0 0 1 0 0 2 15 0 Pied-billed Grebe 0 2 1 0 0 0 0 0 0 0 Horned Grebe 0 1 1 0 5 0 4 5 5 0 Eared Grebe 3 0 3 0 0 0 0 0 0 0 Aechmophorus spp. 1342 484 453 571 609 1895 396 1253 3072 770 Brown Pelican 1 2 4 1 0 0 0 0 0 0 Double-crested Cormorant 136 66 2 3 3 106 0 101 0 0 American Coot 260 335 191 51 0 8 0 0 265 0 Ring-billed Gull 0 3 2 0 2 16 2 0 4 0 Western Gull 2 3 3 1 0 40 7 12 212 14 Glaucous-winged Gull 0 0 0 1 0 0 0 0 0 0 gull spp. 26 93 25 0 19 69 14 33 69 75 Forster's Tern 2 0 0 0 4 0 0 1 0 0

2393 3410 4063 2247 3640 2703 1040 2614 5261 1762

Appendix 8. Numbers of waterbirds on censuses of Richardson Bay Audubon Sanctuary, 1997–98.

16 Oct 2 8 Oct 1 1 Nov 2 7 Nov 11 Dec 3 0 Dec 13 Jan 2 7 Jan 2 4 Feb 1 2 Mar 2 5 Mar

Canada Goose 0 0 0 5 0 0 0 0 0 0 0 Mallard 28 0 0 0 5 2 2 0 0 0 1 Greater Scaup 0 0 0 18 0 0 13 0 0 0 0 Lesser Scaup 0 0 8 0 0 0 0 0 0 0 0 scaup spp. 0 36 72 491 1071 980 1355 894 101 630 53 Surf Scoter 8 10 6 6 9 14 60 19 31 89 165 White-winged Scoter 0 0 0 0 0 0 0 2 0 0 0 Bufflehead 5 3 20 34 16 31 84 63 36 53 26 Common Goldeneye 0 0 0 0 7 1 2 0 0 0 0 Hooded Merganser 0 0 0 0 1 0 0 0 0 0 1 Red-breasted Merganser 0 0 0 0 0 3 2 1 0 0 3 Ruddy Duck 478 1080 836 1055 823 832 884 508 69 6 0 Red-throated Loon 0 0 0 0 0 0 0 1 0 0 0 Pacific Loon 0 0 0 0 0 1 0 0 2 0 0 Common Loon 0 0 0 0 1 0 1 2 0 7 1 loon spp. 0 0 0 0 0 0 0 0 13 87 0 Pied-billed Grebe 0 1 0 0 0 0 0 0 0 0 0 Horned Grebe 8 7 3 4 5 2 3 5 3 4 3 Eared Grebe 1 0 1 0 0 0 1 0 0 0 0 Western Grebe 0 0 0 0 0 0 0 0 0 973 0 Aechmophorus spp. 378 296 500 663 517 424 678 604 564 0 754 Brown Pelican 1 0 2 2 2 5 6 3 0 0 0 Double-crested Cormorant 5 7 11 82 9 0 83 3 30 0 0 American Coot 49 162 116 79 28 10 9 16 4 2 164 Ring-billed Gull 1 2 2 8 12 27 8 0 6 0 0 California Gull 0 0 0 0 0 0 1 1 0 0 0 Western Gull 1 0 0 6 2 2 23 6 0 2 2 Glaucous-winged Gull 0 0 0 0 0 0 0 0 1 0 0 Forster's Tern 1 1 0 2 0 0 0 0 0 0 3 waterbird spp. 0 0 0 0 0 0 0 0 0 600 0

Totals 964 1605 1577 2455 2508 2334 3215 2128 860 2453 1176

Appendix 9. Numbers of waterbirds on censuses of Richardson Bay Audubon Sanctuary, 1998–99.

27 Oct 3 Nov 17 Nov 1 Dec 15 Dec 5 Jan 19 Jan 2 Feb 2 Mar 16 Mar

Canada Goose 0 0 0 0 0 0 0 0 6 0 scaup spp. 54 1075 781 854 1182 2897 1620 302 870 2085 Surf Scoter 36 0 0 0 15 8 6 11 14 0 White-winged Scoter 0 0 0 1 0 0 0 0 0 0 Bufflehead 56 185 174 71 135 54 38 70 24 234 Common Goldeneye 0 1 0 24 0 0 7 3 2 5 Red-breasted Merganser 0 0 12 12 9 0 0 0 0 18 Ruddy Duck 205 1208 1642 3183 5425 2392 938 1747 1640 813 Pacific Loon 0 0 0 0 1 0 0 0 0 0 Common Loon 0 0 0 0 0 0 0 0 6 2 loon spp. 0 0 0 0 0 1 0 0 32 0 Horned Grebe 4 7 4 10 14 15 3 18 2 11 Eared Grebe 0 0 1 1 0 0 0 0 0 2 Aechmophorus spp. 43 283 76 278 159 289 119 394 514 713 Brown Pelican 0 1 5 6 5 1 0 3 0 3 Double-crested Cormorant 0 250 8 13 18 3 0 2 64 3 American Coot 310 349 160 43 34 45 16 66 28 157 Mew Gull 1 0 0 0 0 0 0 0 0 0 Ring-billed Gull 0 10 22 5 0 0 0 16 18 7 Western Gull 5 7 5 20 2 7 21 14 3 3 Glaucous-winged Gull 0 0 0 0 1 0 0 0 0 0 gull spp. 0 21 64 0 0 157 0 60 0 0 Forster's Tern 8 0 0 0 35 20 0 0 0 2

722 3397 2954 4521 7035 5889 2768 2706 3223 4058

Appendix 10. Numbers of waterbirds on censuses of Richardson Bay Audubon Sanctuary, 2006–07.

27 O ct 17 Nov 25 Nov 5 Jan 21 Jan 5 Feb 18 Feb 16 Mar Canada Goose 0 0 0 0 0 0 1 11 American Wigeon 0 0 0 0 6 0 0 0 Mallard 0 10 15 3 16 10 6 8 Canvasback 0 0 0 0 16 5 13 0 Redhead 0 0 0 0 1 0 0 0 Greater Scpau 0 5 303 175 685 295 99 81 Lesser Scaup 0 0 0 42 25 0 17 0 scaup spp. 1 149 19 639 411 778 249 22 Surf Scoter 0 1 0 11 533 1 0 4 Bufflehead 127 504 523 766 741 1631 375 33 Common Goldeneye 0 14 21 42 18 12 3 0 Hooded Meanserrg 0 0 0 0 1 0 0 0 Red-brea sted Merganser 0 15 5 3 40 8 5 6 Ruddy Duck 353 942 373 1383 144 1164 480 658 Red-throated Loon 0 0 0 2 4 0 4 1 Common Loon 0 2 1 2 0 1 0 4 Pied-billed Grebe 2 0 1 0 0 0 0 0 Horned Grebe 44 11 5 16 14 5 5 13 Red-necked Grebe 0 1 0 0 0 0 0 0 Eared Grebe 8 12 1 18 10 19 23 24 Podiceps spp. 21 10 0 0 1 0 0 5 Western Grebe 24 6 18 63 211 2 128 286 Clark's G rebe 3 2 5 8 1 4 2 64 Aechmophorus spp. 111 126 106 154 19 318 11 6 Brown Pelican 1 1 22 7 2 0 0 0 Double-cre sted Cormorant 10 5 281 32 770 2014 206 1284 Great Blue Heron 0 0 1 0 1 0 0 1 Snowy Egret 0 0 0 0 0 0 0 1 American Coot 161 137 155 85 91 63 115 124 Killdeer 0 6 1 0 5 3 4 4 Black Oystercatcher 0 0 0 0 0 1 0 0 Willet 2 1 0 0 0 3 0 0 Spotted Sapipernd 0 2 1 4 2 2 0 3 Black Turnnesto 2 0 0 0 0 0 0 0 Sanderling 0 5 0 0 0 124 0 6 Western Sandpiper 0 1 0 0 0 0 0 0 Least Sandpiper 0 122 201 0 3 3 0 69 Dunlin 0 2 0 120 0 0 0 0 small sandpiper spp. 0 0 0 0 7 72 100 0 Mew Gull 0 0 0 0 8 98 0 0 Ring-billed Gull 0 0 8 6 4 57 0 2 California Gull 0 1 1 9 81 54 2 5 Herring Gull 0 0 0 1 2 0 0 1 Western Gull 27 9 36 9 223 37 1 3 Glaucous-win ged Gull 0 0 0 0 25 0 0 0 gull spp. 11 1 18 30 319 88 528 52 Caspian Tern 0 0 0 0 0 0 0 1 Elegant Tern 0 2 0 0 0 0 0 0 Forster's Tern 6 17 0 0 0 0 0 45 914 2122 2121 3630 4440 6872 2377 2827 34

Appendix 11. Numbers of waterbirds recorded in the Tiburon subarea of the Marin County (southern) Christmas Bird Count, 1978–1992.

Species 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991

Greater White-fronted Goose 0 0 0 0 0 0 0 0 1 0 0 0 0 0 Canada Goose 3 0 1 0 0 0 0 0 0 0 0 0 0 0 Brant 0 0 0 0 1 0 0 0 0 0 0 0 0 0 Wood Duck 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Eurasian Wigeon 0 1 1 0 0 0 0 0 0 0 0 0 0 0 American Wigeon 300 368 150 1 2 14 16 24 16 0 2 6 77 9 Mallard 29 44 22 17 73 21 12 75 37 14 15 39 60 21 Blue-winged Teal 0 0 0 0 0 0 0 0 0 0 0 0 1 0 Cinnamon Teal 0 0 2 0 0 0 0 0 0 0 0 0 0 0 Northern Shoveler 0 31 150 0 6 0 1 0 0 0 0 0 0 0 Northern Pintail 100 36 212 50 0 0 5 3 1 16 6 0 3 0 Green-winged Teal 1 0 25 0 0 0 0 1 0 0 0 0 2 0 Canvasback 2026 468 1153 824 941 410 68 45 11 49 50 83 45 57 Ring-necked Duck 2 1 3 0 1 0 0 0 1 0 1 0 0 4 Tufted Duck 0 0 1 0 0 0 0 0 0 1 0 0 0 0 Greater Scaup 3006 2610 6 1500 20 204 0 2 28 63 700 260 60 184 Lesser Scaup 9008 5740 2 4500 2310 415 37 3500 860 300 350 220 54 0 scaup spp. 0 0 1150 0 570 1020 79 0 667 170 500 0 1070 303 Surf Scoter 4095 9000 4477 5346 86 872 42 275 300 98 300 1256 35 8 White-winged Scoter 10 264 78 468 5 11 25 2 0 0 0 0 0 0 Black Scoter 1 1 0 0 0 0 0 0 0 0 0 0 0 0 Long-tailed Duck 0 1 1 1 0 0 0 0 0 0 0 0 0 0 Bufflehead 512 330 117 430 83 198 23 210 174 128 25 147 145 62 Common Goldeneye 80 260 115 315 28 89 39 46 50 22 15 100 29 20 Barrow's Goldeneye 3 6 0 12 8 22 22 21 19 3 16 30 20 4 Hooded Merganser 0 0 0 0 0 0 0 0 0 0 8 7 11 2 Common Merganser 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Red-breasted Merganser 66 50 19 30 17 27 3 20 8 17 20 35 5 9 Ruddy Duck 8010 5700 2306 9404 773 463 534 2500 789 400 500 845 1150 1001 Red-throated Loon 35 92 1 52 6 147 0 0 3 10 35 29 3 0

Appendix 11 (continued)

Species 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991

Pacific Loon 8 23 1 5 0 220 0 3 1 1 2 1 0 11 Common Loon 8 18 2 9 3 12 0 9 4 3 3 3 3 2 loon spp. 0 0 0 0 4 0 1 2 0 0 0 0 0 0 Pied-billed Grebe 1 4 3 0 6 7 4 4 5 2 9 9 3 2 Horned Grebe 102 61 6 22 4 16 7 6 14 10 0 6 15 4 Red-necked Grebe 0 2 1 6 0 0 0 0 0 0 0 0 0 0 Eared Grebe 10 25 2 11 9 1 1 1 1 0 0 0 0 Western Grebe 4081 3525 3313 13040 637 4990 778 600 604 810 1200 241 365 27 Clark’s Grebe 0 0 0 0 0 0 0 29 54 13 25 36 174 4 Aechmophorus spp. 0 0 0 0 0 0 0 375 589 575 500 60 718 388 Brown Pelican 20 5 0 6 3 18 0 0 0 5 1 1 0 4 Brandt's Cormorant 0 22 30 91 34 1 210 0 0 1 1 0 4 1 Double-crested Cormorant 2453 3710 2702 1163 211 589 71 433 86 35 22 51 42 55 Pelagic Cormorant 0 4 7 9 8 0 0 5 1 0 2 1 1 1 Great Blue Heron 11 18 14 3 7 3 4 6 1 2 3 10 5 0 Great Egret 2 1 3 3 1 2 9 2 5 2 2 4 1 1 Snowy Egret 5 4 6 12 5 2 3 7 11 9 4 13 5 2 Green Heron 0 1 0 0 0 0 0 0 0 0 0 0 0 0 Black-crowned Night-Heron 0 4 8 6 9 10 6 9 17 18 22 15 1 1 Virginia Rail 5 1 1 0 0 0 0 1 1 1 1 5 4 0 Sora 3 2 1 0 0 1 0 0 1 2 0 0 0 0 Common Moorhen 0 0 0 0 0 0 0 0 0 0 0 0 0 0 American Coot 525 201 101 350 82 64 53 170 50 52 35 12 22 35 Black-bellied Plover 2 17 13 3 9 2 5 32 7 25 7 26 26 14 Killdeer 15 20 19 13 3 3 31 20 25 10 15 17 33 6 American Avocet 6 2 0 0 0 2 0 3 2 0 0 0 8 0 Greater Yellowlegs 0 2 0 0 0 0 0 1 2 0 0 0 0 0 Willet 40 75 43 49 25 17 14 32 55 66 25 33 84 21 Spotted Sandpiper 2 9 17 4 9 3 5 3 3 3 4 6 1 5 Long-billed Curlew 0 1 0 0 0 0 0 1 2 3 1 3 3 1 Marbled Godwit 0 9 1 2 0 6 8 2 0 7 5 0 2 0 Black Turnstone 0 12 0 1 0 0 2 4 4 0 0 1 0 0 Sanderling 90 84 28 810 6 3 5 55 238 27 100 56 15 0

Appendix 11 (continued)

Species 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991

Western Sandpiper 272 160 313 20 86 0 7 2 87 4 3 83 168 189 Least Sandpiper 1777 650 12 0 2 0 0 40 33 280 45 35 12 114 Dunlin 1000 594 0 38 25 0 46 150 526 750 280 2200 218 6 sandpiper spp. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 dowitcher spp. 0 25 0 0 0 0 0 0 0 0 0 0 7 0 Wilson's Snipe 1 0 0 0 0 1 0 0 0 0 0 0 0 0 Red Phalarope 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Bonaparte's Gull 10 17 18 4 11 1 3 10 22 15 5 11 15 6 Heermann's Gull 0 2 0 0 0 1 1 0 0 0 0 0 0 1 Mew Gull 1530 5500 80 1824 27 193 76 230 60 286 140 75 150 6 Ring-billed Gull 1640 3200 22 2504 1064 230 65 90 163 175 75 190 160 59 California Gull 1400 1843 56 7607 1147 306 59 225 295 309 603 1730 174 55 Herring Gull 325 610 2 700 6 21 9 2 5 4 2 1 0 1 Thayer's Gull 3 9 1 0 0 0 1 1 1 3 1 7 3 0 Western Gull 1100 2120 235 7675 151 280 205 375 69 135 300 292 116 16 Glaucous-winged Gull 3075 6600 30 7563 165 310 81 145 255 50 500 160 40 4 Glaucous Gull 0 1 0 0 0 0 0 0 0 0 0 0 0 0 gull spp. 0 0 0 0 5500 8000 450 0 104 16 12 216 400 100 Forster's Tern 6 2 5 0 8 0 0 4 12 6 5 1 10 1 Common Murre 10 1 0 0 0 0 0 0 0 0 0 0 0 0

Totals 55898 74082 17514 94376 22248 28576 4072 10881 7332 5985 8136 11339 6821 3068

Appendix 12. Numbers of waterbirds recorded in the Tiburon subarea of the Marin County (southern) Christmas Bird Count, 1993–2005.

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

Greater White-fronted Goose 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Canada Goose 0 0 0 4 0 0 0 0 6 0 0 2 36 26 Brant 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Wood Duck 0 0 0 0 0 0 0 0 0 1 0 0 0 0 Eurasian Wigeon 0 0 0 0 0 0 0 0 0 0 0 0 0 0 American Wigeon 8 5 0 0 0 15 9 9 14 0 3 15 1 0 Mallard 74 23 10 62 43 38 55 67 59 32 13 17 47 10 Blue-winged Teal 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Cinnamon Teal 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Northern Shoveler 0 0 0 0 0 0 0 1 4 0 0 0 0 0 Northern Pintail 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Green-winged Teal 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Canvasback 58 40 55 12 19 26 13 13 19 17 17 14 4 0 Ring-necked Duck 4 4 12 4 6 10 14 6 15 3 4 15 9 0 Tufted Duck 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Greater Scaup 0 22 20 5 100 110 6 6750 1555 1034 27 276 39 0 Lesser Scaup 189 13 44 18 0 205 401 40 116 15 427 86 31 0 scaup spp. 153 792 2400 520 696 122 2167 12 0 0 0 226 1136 2328 Surf Scoter 1 3 60 5 250 433 94 17 11 41 2 60 131 2 White-winged Scoter 0 1 0 0 0 0 0 0 0 0 0 0 0 0 Black Scoter 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Long-tailed Duck 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Bufflehead 83 102 245 25 165 44 383 96 165 47 25 79 390 25 Common Goldeneye 20 27 15 331 210 10 128 35 63 11 5 24 50 49 Barrow's Goldeneye 14 0 0 0 1 3 3 8 5 0 4 2 1 11 Hooded Merganser 0 6 12 6 2 13 6 11 12 9 9 26 0 10 Common Merganser 0 0 0 1 0 1 0 2 0 2 2 1 0 0 Red-breasted Merganser 15 16 10 6 2 14 20 3 12 1 4 1 6 7 Ruddy Duck 2350 237 1525 1126 308 55 618 2069 1117 596 171 1528 743 516 Red-throated Loon 5 4 0 3 0 1 0 1 0 6 0 0 0 0 Pacific Loon 26 0 0 15 0 0 0 0 0 0 0 0 0 0 Common Loon 11 3 0 2 3 0 3 1 0 1 1 1 1 0 loon spp. 0 0 0 0 0 0 0 3 0 0 0 0 0 0

Appendix 12 (continued)

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

Pied-billed Grebe 5 7 8 6 8 16 4 13 5 6 6 8 7 10 Horned Grebe 8 4 5 4 0 8 23 10 0 2 10 4 12 3 Red-necked Grebe 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Eared Grebe 0 0 2 1 3 8 3 1 4 6 3 1 7 0 Western Grebe 631 232 150 526 33 203 144 153 211 310 120 48 77 105 Clark’s Grebe 30 124 56 127 49 25 96 360 58 6 19 13 7 0 Aechmophorus spp. 250 693 100 98 265 0 54 286 0 0 0 57 0 0 Brown Pelican 4 4 0 17 19 8 1 0 7 10 20 0 15 4 Brandt's Cormorant 0 0 0 0 0 0 8 0 0 0 0 1 0 0 Double-crested Cormorant 85 107 8 1424 670 112 76 54 111 40 27 948 84 374 Pelagic Cormorant 2 2 0 0 0 0 0 0 0 0 0 0 0 0 Great Blue Heron 3 0 2 8 2 4 3 7 9 5 4 7 1 2 Great Egret 4 3 1 9 5 13 4 3 4 9 3 0 2 6 Snowy Egret 2 7 6 12 6 27 2 2 4 18 3 8 5 22 Green Heron 1 0 0 0 0 0 0 0 0 0 0 1 0 0 Black-crowned Night-Heron 1 0 0 2 2 1 1 1 0 0 0 0 0 1 Virginia Rail 5 0 0 4 2 0 4 2 4 3 0 0 3 0 Sora 0 0 0 0 1 0 2 3 2 0 0 0 0 0 Common Moorhen 0 0 0 0 0 0 0 0 0 1 0 0 0 0 American Coot 37 16 15 20 30 33 165 136 135 9 46 24 25 59 Black-bellied Plover 34 8 20 11 0 10 3 0 1 1 0 1 0 6 Killdeer 1 5 0 0 0 2 11 12 10 1 0 1 2 3 American Avocet 0 0 0 0 0 0 0 0 0 12 0 3 0 0 Greater Yellowlegs 0 0 0 1 0 0 0 0 0 1 0 1 0 0 Willet 28 41 65 28 16 14 35 30 16 18 6 15 4 17 Spotted Sandpiper 3 0 8 2 1 4 8 6 4 7 3 3 1 4 Long-billed Curlew 1 1 0 1 0 2 0 0 0 1 0 0 0 2 Marbled Godwit 1 4 2 4 0 1 4 0 0 0 0 0 0 6 Black Turnstone 20 0 0 4 22 1 22 0 0 0 0 0 0 20 Sanderling 26 22 50 122 1 232 49 98 46 0 40 62 3 50 Western Sandpiper 63 3160 25 9 40 62 10 22 150 0 0 0 0 0 Least Sandpiper 65 0 22 5 0 0 20 0 72 0 0 0 60 0 Dunlin 29 1405 0 105 80 0 60 120 600 20 26 0 0 0

Appendix 12 (continued)

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 sandpiper spp. 0 0 50 0 0 0 500 0 0 35 0 0 0 0 dowitcher spp. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Wilson's Snipe 0 0 0 0 0 0 0 2 0 0 0 0 0 0 Red Phalarope 0 0 0 0 0 0 0 0 0 0 0 0 0 15 Bonaparte's Gull 3 0 0 0 0 0 0 0 0 0 0 0 0 0 Heermann's Gull 0 0 0 0 0 0 1 0 0 0 0 0 0 0 Mew Gull 0 2 0 68 0 6 0 0 0 26 0 0 0 25 Ring-billed Gull 134 25 45 240 60 80 151 116 329 149 178 30 36 12 California Gull 21 92 30 5604 1 30 219 5 2 257 22 3 0 1 Herring Gull 0 4 11 0 0 306 0 0 0 1 0 0 0 0 Thayer's Gull 0 0 0 1 0 2 2 0 0 1 0 0 0 0 Western Gull 0 20 260 179 40 209 66 41 93 27 9 47 88 5 Glaucous-winged Gull 21 2 156 222 0 17 4 3 0 5 2 0 0 24 Glaucous Gull 0 0 0 0 0 0 0 0 0 0 0 0 0 0 gull spp. 75 150 3062 1095 180 322 1002 6 0 6 0 56 10 1030 Forster's Tern 7 5 0 15 0 12 11 3 0 17 6 38 0 0 Common Murre 0 0 0 0 0 0 0 0 0 0 0 0 0 0

4862 7738 12131 19528 3622 3842 8132 10810 5474 3298 1478 3889 3208 5887

Appendix 13. Numbers of wading birds and shorebirds on 10 censuses of Richardson Bay during the Pacific Flyway Project, 1988–1993.

10 Sep 19 Aug 8 Sep 23 Nov 16 Apr 22 Apr 14 Apr 27 Apr 18 Apr 24 Apr 1988 1989 1990 1991 1988 1989 1990 1991 1992 1993

Great Blue Heron 1 2 0 0 0 0 0 0 0 0 Great Egret 1 3 0 0 2 1 1 0 0 0 Snowy Egret 2 4 0 0 4 3 4 0 0 0 Black-crowned Night-Heron 0 3 0 0 0 0 0 0 0 0 Black-bellied Plover 4 2 11 19 2 1 4 1 4 0 Semipalmated Plover 0 0 1 0 0 0 0 0 0 0 Killdeer 9 4 5 2 1 4 0 1 0 0 Greater Yellowlegs 2 0 0 0 0 0 0 1 2 0 Willet 15 12 16 46 3 0 10 2 6 0 Spotted Sandpiper 0 2 6 1 0 2 2 1 1 0 Whimbrel 0 1 0 0 0 0 0 0 0 1 Long-billed Curlew 0 8 2 0 0 0 0 1 0 0 Marbled Godwit 7 7 6 0 0 1 1 0 3 0 unidentified large sandpiper 0 2 0 0 0 0 0 0 0 0 Western Sandpiper 0 109 50 0 0 0 0 0 0 31 Least Sandpiper 0 0 147 0 0 0 0 0 0 3 Least or Western sandpiper 60 0 0 0 0 0 0 0 0 0 Dunlin 0 0 0 8 0 0 0 6 0 0 dowitcher spp. 0 0 0 0 9 0 0 0 0 0

Totals 101 159 244 76 21 12 22 13 16 35

Appendix 14. Mean numbers of waterbirds on winter (15 Nov–15 Mar) censuses of Richardson Bay Audubon Sanctuary, 1982–83 to 2006–07 (n, number of censuses in the winter period; –, birds of that species and species group not counted in that year).

1982–83 1985 1987–88 1988–89 1989–90 1995–96 1996–97 1997–98 1998–99 2006–07 (n = 9) (n = 4) (n = 6) (n = 5) (n = 6) (n = 8) (n = 7) (n = 7) (n = 7) (n = 6)

Canada Goose 0.0 0.0 0.2 0.0 0.0 0.0 0.0 0.7 0.9 0.2 American Wigeon 0.0 7.0 0.5 0.0 0.5 0.0 0.0 0.0 0.0 1.0 Mallard 0.0 5.0 4.0 1.6 3.5 1.1 0.3 1.3 0.0 10.0 Cinnamon Teal 0.0 2.0 0.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Northern Pintail 1.9 20.0 3.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Canvasback 118.3 271.3 0.0 0.0 0.7 0.0 0.0 0.0 0.0 5.7 Redhead 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 scaup spp. 2108.7 994.5 811.0 343.4 311.3 2149.1 792.1 793.3 1215.1 648.5 Surf Scoter 111.8 6.0 42.3 147.6 15.0 6.4 19.3 32.6 7.7 91.0 White-winged Scoter 5.3 0.3 0.0 13.0 0.0 0.0 0.0 0.3 0.1 0.0 Bufflehead 13.1 54.3 8.5 1.0 266.7 67.9 213.3 45.3 80.9 756.7 Common Goldeneye 4.1 0.0 0.8 0.0 44.0 2.3 0.7 1.4 5.1 18.3 Barrow's Goldeneye 0.7 0.0 0.0 0.0 0.5 0.0 0.0 0.0 0.0 0.0 Hooded Merganser 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.2 Red-breasted Merganser 1.3 0.8 0.2 0.0 7.7 1.8 0.9 0.9 4.7 12.7 Ruddy Duck 1839.8 3492.0 613.3 398.6 861.5 1697.4 685.3 596.7 2423.9 747.7 Red-throated Loon 1.8 0.0 0.0 0.0 0.8 1.5 1.3 0.1 0.0 1.7 Pacific Loon 0.6 0.3 0.0 0.0 0.0 0.4 0.0 0.4 0.1 0.0 Common Loon 0.3 1.0 0.0 0.0 0.0 0.8 2.0 1.6 0.9 1.0 loon spp. 0.0 0.0 0.0 0.0 0.0 2.8 2.6 14.3 4.7 0.0 Pied-billed Grebe 0.1 0.5 0.0 0.0 0.3 0.0 0.1 0.0 0.0 0.2 Horned Grebe 3.0 4.3 1.2 0.0 0.5 1.6 2.9 3.7 9.4 9.3 Red-necked Grebe 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 Eared Grebe 4.7 5.3 5.3 0.0 7.3 0.9 0.4 0.1 0.3 13.8 Podiceps spp. 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.8 Aechmophorus spp. 45.4 2072.0 426.5 111.4 357.5 930.0 1178.4 631.9 261.3 197.3 Brown Pelican 0.8 0.0 1.0 0.0 0.3 1.8 0.7 2.6 2.9 5.3 Brandt's Cormorant 0.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Double-crested Cormorant 183.1 39.5 11.3 0.8 289.7 59.5 30.7 29.6 15.4 551.3 Great Blue Heron 1.3 2.0 2.2 0.0 0.0 0.6 — — — 0.3 Great Egret 1.1 2.3 1.3 0.0 0.0 0.9 — — — 0.0 Snowy Egret 2.6 5.5 1.5 0.0 0.2 1.0 — — — 0.0

Appendix 14 (continued)

1982–83 1985 1987–88 1988–89 1989–90 1995–96 1996–97 1997–98 1998–99 2006–07 (n = 9) (n = 4) (n = 6) (n = 5) (n = 6) (n = 8) (n = 7) (n = 7) (n = 7) (n = 6)

Black-crowned Night-Heron 0.6 0.0 1.0 0.0 0.0 0.1 — — — 0.0 American Coot 7.2 41.0 10.5 1.6 2.5 12.6 73.6 21.1 56.0 107.7 Black-bellied Plover 2.3 3.8 3.8 2.2 1.2 3.8 — — — 0.0 Killdeer 1.7 6.0 0.0 0.0 1.5 0.3 — — — 3.2 Black Oystercatcher 0.0 0.0 0.0 0.0 0.0 0.0 — — — 0.2 American Avocet 0.2 0.0 0.0 0.0 0.0 0.0 — — — 0.0 Greater Yellowlegs 0.2 0.0 0.0 0.0 0.0 0.3 — — — 0.0 Willet 16.0 70.5 19.8 7.0 1.5 19.3 — — — 0.7 Spotted Sandpiper 1.3 1.0 0.3 0.6 0.0 0.8 — — — 1.8 Long-billed Curlew 0.1 1.3 0.8 0.4 0.3 0.5 — — — 0.0 Marbled Godwit 0.6 0.3 0.0 1.0 0.0 0.9 — — — 0.0 Black Turnstone 2.6 0.0 0.0 9.8 4.8 3.6 — — — 0.0 Sanderling 0.0 46.3 4.8 0.4 2.0 32.6 — — — 21.5 Western Sandpiper 10.0 0.0 37.0 0.0 33.3 6.3 — — — 0.2 Least Sandpiper 10.8 10.0 0.0 0.4 0.0 20.5 — — — 54.8 Dunlin 1.3 0.0 0.2 0.0 16.7 30.4 — — — 20.3 Calidris spp. 0.0 0.0 1.7 24.0 322.5 94.0 — — — 29.8 gull spp. 108.2 301.7 82.0 111.4 35.7 478.1 75.9 15.0 59.3 276.0 Elegant Tern 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.3 Forster's Tern 5.9 5.5 3.0 3.6 0.2 8.0 0.7 0.3 7.9 2.8 Common Murre 0.1 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0