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Bulletin Board
Delta Smelt Abundance Patterns
The mystery question puzzling scientists at the State of the Estuary conference this October was why Delta smelt do well in odd years and poorly in even? A pattern seems to be emerging of low abundance in 1992, 1994 and 1996 and high in the years in-between, but biologist Bruce Herbold - the last but most mindbending speaker at the three-day event - hasn't a clue why. Is it copper running off upstream rice fields in certain years? Or the Navy painting the mothball fleet at Vallejo near smelt hang-outs with anti-fouling paint every other year?
What makes smelt happy was just one of the many questions explored by the dozens of scientists who shared their latest estuarine research on the first and second days of the conference, then collected in hallways in the throng of over 400 attendees to share more data and ideas one on one. The conference, rated an overwhelming "excellent" on evaluation forms - covered fish, exotic species, flows, contaminants, wetlands, watersheds, new policy directions and key progress in implementing its organizer's - the S.F. Estuary Project - 1993 Comprehensive Conservation and Management Plan for the Bay and Delta (see workbook Now in Print). A State of the Estuary report summarizing conference findings is due out later this year. (510)286-0460
Valensin Ranch Preserved
A beautiful 4,300 acre ranch on the Cosumnes River was snatched from the onward march of urban expansion and vineyard development south of Sacramento this fall, when a group of private and public agencies led by the Nature Conservancy secured final financing and signed a contract to purchase it. The Valensin Ranch - preserved intact in family ownership from the days of the Mexican land grants - is "a strategic addition" to the 5,000 acre Cosumnes River Preserve, according to the Conservancy's Mike Eaton. Valensin includes more than 500 acres of seasonal wetlands, 12 miles of stream courses and a 300-acre grove of valley oak, as well as productive farmland. Eaton says its protection will also enhance water quality for the existing preserve and river downstream, and link the hydrology of the upper and lower river systems. The $12 million dollars needed to purchase it includes $2 million from private donors and a linchpin grant of $2.5 million in federal transportation funds requiring enhancements. (916)449-2857
Invasive Species Act
The National Invasive Species Act passed Congress this October but failed to move the nation from voluntary to mandatory ballast water control regulations. Ballast water exchanged by ships as they move from port to port has been identified as a major means of transport for foreign invaders of estuarine ecosystems. Over 230 exotic clams, worms, snails, fish, crabs and other organisms have been found in the Bay and Delta as of 1996 - some of them are threatening the base of the food chain, others may soon undermine levees and clog drinking water intakes.
Though the new act (HR4283) expands the nation's efforts to prevent invasions from the Great Lakes region to the entire country, it's still not as stringent as many Bay Area scientists, water users, managers and environmentalists would have liked. "It's a bill without a tooth in it," says biologist Andy Cohen. A baby tooth, perhaps, is a requirement that the Secretary of Transportation develop a strategy for assessing and ensuring compliance with the act's guidelines, including a strategy specific to the Bay Area. Congressman George Miller and other California lawmakers succeeded in getting the bill modified to help their state. Such modifications included up to $750,000 for research on aquatic nuisance species prevention and control in the S.F. Bay -Delta Estuary (as well as $500,000 for Pacific Coast research); addition of a Bay-Delta representative to the existing National Task Force (see calendar); and creation of a new panel to identify and coordinate priorities for the Pacific Coast. Contact: Debbie Colbert (202)226-7256
"Red List" for Endangered Species
California's white abalone are among 100 oceanic species being added to the World Conservation Union's "red list"' of creatures vulnerable to or nearing extinction this fall. The marine red list is part of the largest study of the state of the world's wildlife ever conducted (evaluating over 5,000 species and using data from over 7,000 scientists). Although it is not news that commercial stocks of ocean fish such as Pacific Coast salmon are rapidly depleting, most scientists have long assumed that the sheer size of the ocean and general fecundity of oceanic species made true endangerment of marine fish and invertebrates next to impossible.
Now some are changing their views. The threats to sharks, seahorses, groupers and other species are the same as those facing many terrestrial creatures: over-exploitation of slow-reproducing species, the destruction of narrow habitats and pollution. However, the red list also includes super-fertile, wide-ranging but severely over-fished species including tuna and swordfish. The red list carries no legal authority; rather it is used a guideline and red flag for policy makers.
Interim South Delta Draft EIS/EIR
Four new barriers and a new water intake were proposed by BurRec and the Department of Water Resources this August to resolve water-level and circulation problems for local agricultural diversions in the South Delta, as well as to improve hydraulic conditions so as to maximize the frequency that the State Water Project's Banks Pumping Plant can pump at full capacity. To address the former, an August 1996 Draft Environmental Impact Statement/ Report (see Now in Print) recommends installation ofpermanent barriers at four South Delta locations - three to better control flows and water levels (at Old River near Tracy, Middle River and Grantline Canal) and one (at head of Old River) to improve conditions for migrating San Joaquin salmon. To address the latter, the EIS/EIR recommends constructing a new intake at the Clifton Court Forebay near the pumping plant, increasing diversions into the Forebay, and dredging a 4.9 mile reach of the Old River just north of the Forebay. Environmentalists and water users contacted concerning the pros and cons of the recommendations had no comment. Comments due on the EIS/EIR by December 6. Contact: Steve Roberts (916)653-2118
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