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Sancutary Program Accomplishments Open Ocean & Deep Water Systems Wetlands and Watersheds Endangered & Threatened Species
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On a more encouraging note, the Reserve is home to a growing rookery of Great Blue Herons and Great Egrets. Volunteers are also adding their powers of observation to assist scientists in monitoring this colony, which has grown from a single nesting pair of herons in 1985 to fifteen heron nests and thirty-eight egret nests in 1998. Several pairs of Double-crested Cormorants have added their nests to the Monterey Pine canopies of this rookery for the second year in a row. The Reserve has only recently been surveyed for the presence and reproductive activity of the California red-legged frog. Observations indicate several sites on the Reserve that are supporting a viable population of this threatened species. It is thought that small coastal drainages, like the Elkhorn Slough watershed, are the only remaining regions in California where the red-legged frog can still be found in significant numbers. This year's surveys indicate that this is one of only four localities in the state supporting populations of more than 350 individuals. The water quality of the fresh water ponds that are being used by the California red-legged frogs is now being monitored by volunteers to provide the data necessary for proper management of these habitats.
While work is being done to contain top soils in the uplands of the watershed, another type of erosion caused by the daily tidal currents is deepening the main channel of the Slough and contributing to the loss of salt marsh. Researchers continue to gather the information necessary to make decisions about which of several proposed hydrodynamic modifications will be the most effective in slowing this trend. From oak woodlands to salt marsh, from sediment movement to nesting birds, collaborations of federal, state, and local agencies/organizations, scientists, and community volunteers are helping us to appreciate and manage this rich and sensitive coastal region better. Kenton Parker
Watershed
Characterization Monitoring
Coastal Estuaries
Monitoring Bay Protection and
Toxic Cleanup Program Final reports for each of the three studies will be available in 1999. Also in 1999, the CCAMP will focus on characterization monitoring of the Salinas watershed. Major ocean dischargers from within the Sanctuary and elsewhere in the Region will be meeting with Regional Board staff early in 1999 to reexamine receiving water monitoring efforts. The goal of this process will be to make better use of resources, to detect impacts resulting from discharges more effectively, and to incorporate an ambient ocean monitoring component into the overall study design. Karen Worcester |
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The
Elkhorn Slough Watershed Project, a collaborative
effort of the Elkhorn Slough Foundation, the
Resource Conservation District of Monterey County,
the USDA - Natural Resources Conservation Service,
and the Sanctuary, has been working closely with
local farmers to prevent loss of topsoil. In
addition to over 20,000 tons of soil that have been
trapped in sediment basins installed on farms
throughout the watershed, recent tests of sediment
samples indicate that agricultural chemicals are
also being successfully contained in these basins
and prevented from working their way downstream
into the Slough. A poignant event which illustrates
the importance of this work occurred in 1995 when
old pesticides buried in the sediments of the
Pajaro and Salinas rivers were stirred up by the
torrential rains and flooding, entered the food
chain, and led to the collapse of a colony of
Caspian Terns that was being closely monitored. The
terns had been thriving on an island in a restored
salt marsh on NOAA's Elkhorn Slough National
Estuarine Research Reserve (ESNERR). Volunteers and
researchers watched closely this year and terns
were seen but did not attempt to nest.
This
is the tenth year of the Reserve's volunteer water
quality monitoring program, a collaboration of
ESNERR, the Elkhorn Slough Foundation, the Monterey
County Water Resources Agency, and highly dedicated
volunteers. Twenty-four sites throughout the
watershed have been sampled monthly for
temperature, salinity, dissolved oxygen, pH,
turbidity, nitrate, ammonium, and dissolved
inorganic phosphate. This is the only long-term
data set on water quality in this region, and has
been essential in documenting some of the highest
inputs of nitrates into the Slough from the lower
Salinas River and the old Salinas River
Channel.
Initial
results show some very high concentrations of
nutrients, coliform, and sediment at a number of
sites in the watershed. At some sites high nutrient
levels were accompanied by excessive algal growth
and reductions in dissolved oxygen, indicating
impairment of stream habitat. Llagas Creek
consistently had the highest levels of nitrates in
the watershed, with the lower Pajaro also quite
elevated. Tres Pinos Creek and the San Benito River
had very elevated levels of sediment, turbidity,
and at times total phosphorus. Tequisquita Slough
was particularly high in ammonia and
orthophosphate, and low in dissolved oxygen. High
levels of zinc, copper, and lead were found in
water at two sites (on the San Benito and the
Pajaro rivers). Benthic invertebrate assemblages
showed a wide range of variability in species
composition. Assemblages on lower Llagas and
Salsipuedes creeks were particularly
impaired.