2008 Annual Monitoring Report (pdf 10.9MB) - Bolsa Chica ...
2008 Annual Monitoring Report (pdf 10.9MB) - Bolsa Chica ...
2008 Annual Monitoring Report (pdf 10.9MB) - Bolsa Chica ...
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<strong>Bolsa</strong> <strong>Chica</strong> Lowlands Restoration <strong>Monitoring</strong><br />
<strong>2008</strong> <strong>Annual</strong> <strong>Report</strong><br />
The extent of these habitats varies greatly (Table 1-3). When standardized by the area of each habitat<br />
type, bird densities in February were greatest in the freshwater areas such as mulefat scrub (1,478<br />
birds/ha), freshwater marsh (121 birds/ha), and willow/riparian (81 birds/ha). In April the bird<br />
densities were highest in mulefat scrub (455 birds/ha), mudflat (134 birds/ha), and decaying<br />
transitional vegetation (104 birds/ha). June had the highest bird densities on the intertidal sand shoal<br />
(199 birds/ha). August bird densities were greatest on the mudflat (128 birds/ha), the intertidal sand<br />
shoal (99 birds/ha), and on the nest site (60 birds/ha). In October the birds densities were highest on<br />
the mulefat scrub (398 birds/ha), decaying transitional vegetation (78 birds/ha), salt panne and<br />
inundated salt panne (39 species/ha), and disturbed salt marsh (37 birds/ha). December bird densities<br />
were greatest in the foraging and resting area such as decaying transitional vegetation (732 birds/ha),<br />
mudflat (82 birds/ha), and the intertidal sand shoal (67 birds/ha).<br />
Flying birds were recorded in the habitat over which they were flying at the time of observation,<br />
though they may not necessarily use that habitat on the ground. Thirteen percent of all birds were<br />
flyovers. To look at species richness, all birds recorded as flying were disregarded and only birds on<br />
the ground considered. Species richness was highest in the salt marsh (85 species), open water (74<br />
species), mudflat (66 species), and inundated salt panne (62 species) (Figure 1-18). All other habitats<br />
had 50 species or less in <strong>2008</strong>.<br />
As noted in the prior annual report, the heavy usage of the intertidal sand shoals in Zone 73 (inlet) at<br />
low tide by gulls, cormorants, terns, and pelicans was not fully captured by these surveys, though<br />
observed regularly in late afternoon low tides at the site. The survey also cannot account for<br />
movement of birds into and out of the survey area from <strong>Bolsa</strong> <strong>Chica</strong> State Beach and from Inner and<br />
Outer <strong>Bolsa</strong> Bay.<br />
Gulls on sand shoal in the Full Tidal Basin.<br />
Discussion<br />
The <strong>Bolsa</strong> <strong>Chica</strong> Lowlands Restoration Project included several elements that have enhanced the avian<br />
community within the project area. The creation of the FTB is the most notable, which involved<br />
removing existing oil wells, excavating a basin, and constructing a permanent opening to the ocean in<br />
2006. Its new mudflats and open water were the most used area in <strong>2008</strong>, providing expansive foraging<br />
and loafing habitat to 91 species, including seven that were found in no other area of the site: brant,<br />
common loon (Gavia immer), common merganser (Mergus merganser), glaucous-winged gull (Larus<br />
glaucescens), pelagic cormorant (Phalacrocorax pelagicus), surf scoter, and western grebe<br />
Merkel & Associates, Inc. 85