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<br />to practice their traditional subsistence of harvesting
<br />Palmer's salt grass (Distichlis palmen) -which has
<br />limited reproductive capability without regular flood-
<br />ing to disperse seeds - the Cucapa have looked to other
<br />harvests the delta supports. Several Cucapa communal
<br />agricultural settlements, or ejidos, line the Pescaderos
<br />River, a tributary of the Colorado now converted to
<br />agricultural drainage, and these communities use the
<br />Pescaderos for fishing and hunting. Diminished flows
<br />in the river have forced many Cucapa to truck their boats
<br />miles to reach the nearest waterways, and many travel
<br />farther to find work in the agricultural fields of the
<br />Mexicali Valley (Boyer, 1998). The Cucapa have the one
<br />licensed commercial fishing operation in the delta - the
<br />Cucapa Fishing Production Unit-which has tribal
<br />rights to fish for Gulf corvina and shrimp. Although
<br />subsistence fishing, as well as hunting and gathering,
<br />once were common, Cucapa communities now work as
<br />hunting and fishing guides, and sell their arts and crafts
<br />to tourists (Valdes-Casillas et aI., 1998a). Other residents
<br />fish commercially in the southernmost Colorado River
<br />between Cucapa EI Mayor and the river's mouth for
<br />bigmouth bass, carp, mullet, catfish, tilapia, and cray-
<br />fish. Commercial fisheries in the upper Gulf, all
<br />dependent on the delta for breeding grounds and/ or
<br />nutrients, include shrimp, shark, milkfish, and corvina
<br />(Valdes-Casillas et aI., 1998d).
<br />
<br />Photo 2. Palmer's saltgrass In the Colorado River delta.
<br />
<br />
<br />
<br />The success of any effort to preserve delta ecosystems
<br />will depend on its ability to identify and include the
<br />interests and concerns of local people and communi-
<br />ties. As part of the research discussed in this report,
<br />social scientists have approached the people of the delta
<br />to begin the process of understanding their needs and
<br />to provide outreach and education concerning the
<br />research effort. In addition, locals are being asked to help
<br />scientists understand the delta's ecology and the ways
<br />in which it has changed in recent decades. (Appendix C
<br />contains a more complete summary of this outreach
<br />effort)
<br />
<br />
<br />GROWING INTERNATIONAL
<br />INTEREST IN THE DELTA
<br />
<br />The past decade has brought greater scientific under-
<br />standing of the Colorado River delta, and it also has
<br />brought increased political interest from both sides of
<br />the border. In 1993, the delta and the upper Gulf were
<br />declared a Biosphere Reserve by the Mexican govern-
<br />ment. This designation, sanctioned by the United
<br />Nations, is designed to protect world-class ecosystems
<br />while encouraging continued sustainable economic ac-
<br />tivity in surrounding buffer areas.9 The Biosphere
<br />Reserve of the Upper Gulf of California and Colorado
<br />River Delta covers a total of 2,309,782 acres (934,756
<br />ha) -407,218 acres (164,779 ha) in the core and 1,902,564
<br />acres (769,976 ha) in the buffer. The core area includes
<br />la Cienega de Santa Clara and eI Doctor wetlands. The
<br />Reserve is designed to protect an estimated 19 percent
<br />of the plant species found in Mexico, 22 of the 37
<br />saltwater fish species endemic to the Gulf of California,
<br />and the desert pupfish, the only surviving native
<br />freshwater fish species of the delta (Centro de
<br />Investigaciones Cientificas y Tecnologicas de la
<br />Universidad de Sonora, n.d.).lO
<br />
<br />The delta was recognized as part of the Western Hemi-
<br />sphere Shorebird Reserve Network in 1992. In 1994,
<br />Mexico joined the U.S. and Canada in the North
<br />American Waterfowl Management Plan, and listed the
<br />delta as continentally important habitat. In 1996, delta
<br />wetlands were listed as a Ramsar site when Mexico
<br />became a party to the -Convention on Wetlands (also
<br />known as the Ramsar Convention) and thereby agreed
<br />
<br />, Biosphere Reserves, designated by the Mexican government under the authority of the General Law of Ecological Equilibrium and Environmental
<br />Protection, can be created to protect areas greater than 25,000 acres (10,000 ha) that contain endemic, threatened, or endangered species (Centro de
<br />Investigaciones Cientificas y Tecnol6gicas de la Universidad de Sonora, n.d.).
<br />10 The Biosphere Reserve's Management Plan cites significant environmental threats to the region such as reduced flows, illegal fishing, agricultural
<br />pollution, illegal hunting, illegal extraction of plants, and overfishing.
<br />
<br />8
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