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

Bolsa Chica Lowlands Restoration Monitoring
2008 Annual Report
196 m 2 of cordgrass had become established in the FTB one year post-transplant. It is expected that
the cordgrass will expand to form continuous patches suitable as habitat for light-footed clapper rails
(Rallus longirostris levipes) within four to five years of transplant.
Investigations of plant species composition along nineteen transects in the restored areas found the
Muted Pocket Marsh (MPM) to support the most diverse salt marsh habitat, with minimal non-native
species. Rabbit Island in the FTB was the second most diverse, but had a higher component of weedy
species, particularly iceplants. A population of the rare plant coast woolly heads (Nemacaulis
denudata var. denudata) persists on Rabbit Island and will need immediate protection through removal
of the iceplant that is encroaching on its remaining populations. The salt marsh in the MTBs is low in
diversity, but forms a dense canopy of pickleweed (Sarcocornia pacifica) that is heavily used by
Belding’s Savannah sparrows (Passerculus sandwichensis beldingi) for nesting each year.
The next full vegetation monitoring event, including aerial photography, habitat mapping, and transect
surveys, will be conducted in summer 2011 (Year 5) as called for in the Monitoring Plan. Additional
photography and habitat mapping will be done in 2009 to document interim conditions.
FISH COMMUNITY
The 2008 fish community sampling was completed in January, April, July, and October. Sampling
was performed during daylight hours at two stations in the FTB, one in the MPM, and two in the
MTBs. Sampling equipment included an otter trawl, purse seine, large beach seine, and small beach
seine as appropriate for the station depth and accessibility. Captured fish were identified, counted,
measured, and weighed. Physical water quality parameters were measured coincident with the fish
sampling efforts.
A total of 42 fish species were captured in 2008 at all stations. Thirty-nine species were captured in
the FTB, dominated by topsmelt (Atherinops affinis) (46% of the total catch), California killifish
(Fundulus parvipinis) (6% of the total catch), and California grunion (Leuresthes tenuis) (9% of the
total catch). Anchovy (Anchoa sp.) comprised only 7% of the total catch and were present primarily in
July. The other species captured were increasingly associated with structured habitats due to the
spread of eelgrass habitat, particularly in the southern half of the basin. Fish densities were generally
low in January and April and much higher in July and October, driven primarily by the number of
atherinids captured.
Ten fish species were captured in the west and central MTB in 2008. Only the west MTB was directly
open to the FTB. Topsmelt and killifish were the most abundant species. Diversity and biomass are
anticipated to increase as the MTBs are all opened to the tidal influence of the FTB in the future.
The MPM, which is hydrologically separate from the restoration project area, was generally found to
be low in diversity but high in abundance of species foraged on by many birds. Nine species were
captured, with topsmelt and California killifish the most abundant year round, reaching their peaks in
July. Staghorn sculpin (Leptocottus armatus) and longjaw mudsucker (Gillichthys mirabilis) were
occasionally abundant.
The restoration project and creation of the FTB has increased the availability of important bay habitat,
provided nursery functions for many species of marine fish, and thereby improved southern California
fisheries resources. Nearly every fish species captured during the 2007 and 2008 monitoring was
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