The
Grasslands
California, USA
International Site
Contact: Assistant General Manager, Grassland Conservation
District
22759 S. Mercey Springs Rd. Los Banos, CA 93635
Tel.
209 826-5188
Fax 209 826-4984
WHSRN Site Location
Fresno and Merced Counties, California, USA
Area
of Site: 78,476 hectares (193,768 acres).
Land
Description:
A mosaic of federal, state, and privately owned
wetlands, representing a third of California's remaining Central Valley
wetlands. The Grasslands is an
intensively managed seasonal and semi-permanent palustrine emergent marsh. Other habitats within the Grasslands include
riparian wetlands, permanent marsh, alkali scrub, native grassland, and
pastoral lands.
Land Use:
The Grasslands is intensively
managed as a wildlife area for waterfowl hunting. Cattle grazing on native pasture occurs on about 20% of the
Grasslands. The area has a very sophisticated
system for water delivery and management.
Protection:
Protection is provided to 58% (112,241 acres) of the Grasslands by virtue of federal and state ownership and by private lands with perpetual conservation easements. Federal, state, and private landowner organizations including the Grassland Water District, Grassland Resource Conservation District, California Waterfowl Association and Ducks Unlimited have identified additional critical areas that must be protected to preserve the Grasslands. These organizations have recently developed the biological justification to establish an agricultural buffer zone between the Grasslands and urban areas. The importance of long-term protection of agricultural use around the Grasslands continues to be one of the highest priorities for the Grassland Water District and the Grassland Resource Conservation District.
The development of an
environmental education center in the Grasslands by the Grassland Resource
Conservation District will include in its curriculum for K-6 students the
recognition of the importance of the Grasslands for shorebirds, waterfowl, and
other wetland dependent species.
Current Threats:
The Grasslands is threatened
with the loss of habitat quantity and quality by urban encroachment, conversion
to intensive agriculture and industry, water pollution, high operation and
maintenance costs, and threats to eliminate waterfowl hunting. The Central
Valley Project (CVP) Improvement Act approved by the U.S. Congress in 1992
provides some of the Grassland with a reliable water supply. However, the long-term status of this
legislation is threatened by political pressure from agricultural interests
adjacent to the Grasslands.
What
Shorebird Species Use This Site?
Censuses conducted by the Point Reyes Bird
Observatory's Pacific Flyway Project for five years in the Grassland shows
about 200,000 shorebirds during the spring (mostly Western Sandpipers,
Long-billed Dowitchers, Dunlins, and Least Sandpipers), about 14,000 shorebirds
during the fall (Long-billed Dowitchers, Least Sandpipers, Black-necked Stilts,
and Least and Western Sandpipers), and about 60,000 shorebirds in the winter
(mostly Long-billed Dowitcher, Dunlin, Least Sandpipers, and Black-necked
Stilts). During the peak of spring
migration in mid-April, the Grasslands holds nearly 50% of all the shorebirds
in the Central Valley of California.
The Grasslands is one of the most important shorebird habitats in the
western U.S. The Grasslands contains
about a third of the wetlands remaining in the Central Valley of California,
which the U.S. Fish and Wildlife Service has identified as the most important
wintering area for waterfowl in the U.S. The area also provides habitat for 46
plants and animals with federal or state endangered, threatened, or candidate
status.
Recent Management & Research Activities:
The management of the Grasslands has improved
significantly since the inclusion of the Grasslands as an international
shorebird reserve. The implementation
of the Central Valley Project Improvement Act in 1993, the purchase and
restoration of about 2,000 acres of wetlands by the USFWS and CDFG, the
implementation of the CDFG California Waterfowl Habitat Program on 7,447 acres
of private lands, annual marsh management workshops sponsored by the GRCD for
private landowners, and technical assistance provided to private wetland owners
by the USFWS, CDFG, and GWD are some of the programs that continue to elevate
wetland management in the Grasslands to state-of-the-art levels.
In 1996, two aspiring graduate students from
Humboldt State University in California completed microhabitat and
winter/spring shorebird response to water level manipulation research in the
Grasslands. The California Department
of Fish and Game, the Western Regional Office of Ducks Unlimited and the
Grassland have gathered information on the importance of shallow water,
fluctuating water levels, gradual water level changes and water management
diversity in winter and spring for waterfowl and shorebirds. The study is continuing to provide
information that will help in the development of a winter and spring flooding
and drawdown regime model for waterfowl and shorebirds in the Grasslands.
Information Relating to WHSRN
Land Owners of Areas Signed on to WHSRN
Mexican Federal Government
Date Site Joined WHSRN: December 1992
Locally Involved
Agencies & Organizations
§
California
Waterfowl Assoc.
§
Ducks
Unlimited, Inc.
§
Sierra
Club
§
National
Audubon Society
§
Natural
Resources Defense Council
§
Campaign
to Save California Wetlands
§
Wilderness Society
Local
Activities& Contacts:
§
Wild
CA Wetland Festival (March)- Festival focuses on wetlands and wildlife within
the Grasslands.
§
“Grassland
Today,” site newsletter written from the Grassland water District. Address: 22759 S. Mercey Springs Rd., Los
Banos, CA 93635
Bibliography
Anderson, D.G.
1956. A waterfowl nesting study
on the Grasslands, Merced County, California.
California Fish and Game 42: 117-130.
Connelly, D.P. 1979. Propagation of selected marsh plants in the San Joaquin
Valley. California Department of Fish
and Game, Wildlife Management Leaflet 15, Sacramento.
13 pp.
Connelly, D.P., and D. L. Chesemore. 1980.
Food habits of pintails, Anas Acuta, wintering on seasonally
flooded wetlands in the northern San Joaquin Valley, California. California Fish and Game 66: 233-237.
Ermacoff, N. 1968.
Marsh and habitat management practices at the Mendota Wildlife
Area. California Department of Fish and
Game, Game Management Leaflet No. 12. 10pp.
Fredrickson, L.H. and M. Laubhan. 1995.
Land Use Impacts and Habitat Preservation in the Grasslands of Western
Merced County, California. A report of
the Grassland Water District, Los Banos, CA.
81pp.
George, H.A. 1963.
Planting alkali bulrush for waterfowl food. California Department of Fish and Game, Game Management Leaflet
9, Sacramento. 9 pp.
Kjelmyr, J., G. Page, W.D. Shuford, L.E.
Stenzel. 1991. Shorebird Numbers in Wetlands of the Pacific
Flyway: A Summary of Spring, Fall,
Winter Counts in 1988, 1989, and 1990.
Miller, A.W., and P.H. Arend. 1960. How to grow watergrass for ducks in
California. California Department of
Fish and Game, Game Management Leaflet No. 1, Sacramento. 16pp.
Noss, R.F. 1994.
Translating conservation principles to landscape design for the
Grassland Water District. Report to
Grassland Water District. Los Banos,
CA. 27pp.
Page, G.W., W.D. Shuford, J.E. Kjelmyr, and L.E.
Stenzel. 1992. Shorebird Numbers In
Wetlands of the Pacific Flyway: A
Summary of Counts From April 1988 to January 1992. Point Reyes Bird Observatory.
Stinson Beach, CA 42pp.
Page, G.W., W.D. Shuford, J.E. Kjelmyr. 1994.
Results of the April, August, and November 1993 Shorebird Counts in the
Wetlands of California’s Central Valley.
Point Reyes Bird Observatory.
Stinson Beach, CA. 11pp.
Reid, T.
1995. Grassland Water District
Land Planning Guidance Study. A report
to the Grassland Water District. Los
Banos, CA 29pp.
Severson, D.J. 1987. Macroinvertebrate populations in seasonally flooded marshes of
the San Joaquin Valley of California.
M.S. Thesis, Humboldt State University, Arcata, CA. 113pp.
Shuford, W.D., G.W. Page, J.E. Kjelmyr, and C.M.
Hickey. 1994. Seasonal Abundance and
Habitat Use of Shorebirds in California’s Central Valley, November 1993 to
August 1994. Point Reyes Bird
Observatory. Stinson Beach, CA. 17pp.
U.S. Bureau of Reclamation, 1989. Report on Refuge Water Supply
Investigations. Central Valley
Hydrologic Basin, California. U.S.
Department of Interior, Mid Pacific Region.
Sacramento, CA.
U.S. Fish and Wildlife Service. 1978. Concept Plan for Waterfowl Wintering Habitat Preservation, Central Valley, California. U.S. Fish and Wildlife Service, Region 1. Portland, OR. 116pp.