2008 Annual Monitoring Report (pdf 10.9MB) - Bolsa Chica ...

Bolsa Chica Lowlands Restoration Monitoring
2008 Annual Report
years of greater tidal muting, the open water areas will be slightly larger, since the low tides won’t fall
to as low an elevation as they would immediately following a dredge event, when tidal muting is
minimized.
Unvegetated Nest Site
This includes Nest Sites 1, 2, & 3. They are topped with sand and groomed to appeal to targeted
sensitive avian species that nest on such sites. Portions of the nest sites that have non-native vegetation
growing at a high enough density as to preclude nesting by the targeted species were excluded from the
total nest site area calculations and mapping instead as non-native vegetation.
Urban/Developed
The areas designated as urban/developed were comprised of paved streets, paved and unpaved oil field
roadways and berm roads, recreational paths, oil pads, or highly disturbed areas adjacent to the
residential neighborhoods or related to oil field operations and contamination remediation.
Salt Marsh Transect Monitoring
The results of the transect monitoring are presented in Table 1-2. At the bottom the table is a summary
of the percent vegetative cover on each transect, disregarding any overlap of species, for all vegetation
and for native species only. Summaries are also provided for native and non-native species,
accounting for overlapping species within the transect. Figure 1-6 presents the mean coverage of
native and non-native species at each of the five survey areas, allowing for overlap of species. The
MPM had very little non-native cover and the FTB transects had none, however it should be noted that
Rabbit Island, which is also located in the FTB, did have non-native species. The FTB transects are all
located on the intertidal mudflats of the north and east shore, where conditions are unfavorable for the
establishment of most non-native species due to regular tidal inundation. The non-native species at
Rabbit Island occur at elevations above the highest high tides.
100
Mean % cover
80
60
40
20
Native Vegetation
Non-native Vegetation
0
Rabbit Island Full Tidal Basin West MTB Central MTB East MTB Muted Pocket
Marsh
Figure 1-6. Mean percent cover (including overlap) of native and non-native vegetation by survey area (2008)
The most abundant non-native species were the iceplants M. nodiflorum and C. edulis, with M.
nodiflorum particularly abundant in the non-tidal portions of the central and east MTBs. The iceplant
remaining in the west MTB was showing signs of stress from the introduction of tidal influence in
March and will likely die in the coming year.
Merkel & Associates, Inc. 29