April 2013 Vol
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ESTUARY science • restoration • watershed • politics • species • Bay san Francisco estuary partnership Sustaining a living estuary like San Francisco Bay is no cakewalk . You’ve got to jive with unpredictable things like invasive clams, seasonal flows, climate change, and restoration budgets . And you’ve got to power through the twists and turns of politics and land use debates . The prize might not be as obvious as a lupine in the spring sunlight . But it sure beats sitting out the last dance… . news april 2013 Vol. 22, no. 2 Herbold Opinion . .2 Clams & Beetles . .3 Drakes in Court . .4 New Bay Observatory . .6 Rain Barrels . .7 International Wetlands . .8 Laid Back Levees . .10 South Bay Flood Study . 11 2 APRIL 2013 ESTUARY news IN BRIEF opinion watershed-wide planning effort focused on flood control. Little of that effort is being implemented. Move on.delta Also seven years ago the collapse OVERBITE CLAM Not SO Retired USEPA biologist Bruce of fish populations brought a surge of SALINITY SENSITIVE — Biologists Herbold reflects on decades of scientific work that greatly deepened are learning more about the habi- impasse and challenges ahead . our understanding of the ecology of tat constraints of the overbite clam the Delta and how various factors (Corbula amurensis). The local range of The Delta has been altered, interacted. A three-year drought the invasive mollusk was assumed manipulated, exploited, and (2007-2009) showed how low flows to be limited by salinity, with reduced fought over to such an extent that intensify the impact of factors metabolic rates where salinity is low. it is now probably California’s like predation, entrainment, and However, a recent article by Nathan most important and intractable contaminants. High flows in 2011 Miller of San Francisco State Univer- problem. As an immensely valu- allowed intense scientific study under sity’s Romberg Tiburon Center and able transport corridor for commerce, very different conditions. We know a lot Jonathon Stillman of UC Berkeley in water, waterfowl, and major fisheries, more than we did 10 years ago; enough Marine Ecology Progress Series calls that and as a landscape that supports local to take bold action with a reasonable into question. Sampling clams from agriculture, recreation, resident fish expectation of rescuing our fish and Suisun Bay, Miller and Stillman found species, and municipal property, the the people they support. Instead we are that salinity explained very little of the Delta has been the focus of much plan- continuing with legal wrangles. metabolic changes observed in dif- ning over the last 20 years. Past efforts In addition, we live in the most ferent seasons. Their study included have included CalFed, the Delta Vision invaded estuary in the world and we the spring of 2011, when unusually process, the Delta Risk Management have a very clear idea of what the next high fresh water depressed salinity. Strategy, the Delta Plan, and presently major invader will be and what it will Another surprise: overbite clams may the Bay-Delta Conservation Plan. do. Freshwater mussels, which can filter more phytoplankton from the But planning is usually based on clog and block water pipes and bedevil water column — and thus compete history, which may no longer be so aquatic ecosystems, spread rapidly more with native species — in winter relevant. At a series of talks in Janu- across North America to Lake Mead and early spring, when their metabolic ary 2013, Professor Geoff Petts of and thence into San Justo Reservoir rates are lowest, than in summer. England’s University of Birmingham (roughly 25 miles from the Central Val- Nathan Miller: CONTACT repeatedly made the point that climate ley). We have done nothing to prepare namiller sfsu.edu JE @ change has rendered the climatic for these invaders, and they are not ad- history of Britain useless for planning dressed in any current planning effort. NEW National water management and ecological res- ESTUARIES LEADER toration. Britain sits on the cusp of the How does one plan for an uncertain, A well-known Southern Gulf Stream and, as tropical and polar dramatically different future? Down- California wetlands conditions vary, conditions in the UK stream, in the San Francisco Bay, advocate is heading to vary enormously. Last year Britain had a great deal of work is underway to Washington to chair the Association the driest winter on record, followed by develop plans to adapt to the impacts of National Estuary Programs (ANEP.) the wettest summer and fall. of climate change and invasive species Shelley Luce, director of the Santa on both ecosystem values and human Monica Bay Restoration Commission, Also in January 2013 an article by infrastructure (integrated planning in- was tapped for a two-year term with Mike Dettinger and Lynn Ingram in cludes such ideas as placing wetlands the national organization. She’ll help Scientific American described how, even to minimize the impacts of storm surge coordinate 28 local programs (three without climate change, California’s on levees). Serious scientific, engineer- in California — San Francisco, Morro, climate is at the whim of trans-Pacific ing, and policy discussions proceed and Santa Monica bays) and foster atmospheric rivers. A 2012 study by over what we can expect, what can be collaboration among them. Luce says USGS estimates the damage of a flood done, what losses are unavoidable, and a key goal will be increasing public substantially smaller than the worst which tools we can afford. understanding and appreciation of flood in California’s history would be local estuaries and the NEPs that pro- devastating; more so than comparable The Delta needs a similar compre- tect them. Her background includes a earthquake analyses. The tremendous hensive, open, imaginative, and realistic UCLA doctorate and experience with flood of 1861, that was the basis for discussion that uses and integrates large-scale wetlands restoration proj- the analysis, had come after a 20 year all the planning done to date. We ects and community-based greenway drought. No one agrees on how climate need goals supported by science that planning. “Shelley Luce continues the change will affect California’s flood and recognize the limited ability we have to tradition of strong, smart, and hard- drought pattern but no one expects the manage resources in the face of major working ANEP chairs we’ve had over unusual stability we enjoyed from 1938 unavoidable impacts. Wishful thinking, the years,” says the San Francisco Es- to 1975. hubris, fear, greed, and expecting- tuary Partnership’s Judy Kelly. “She’s the-future-to-be-like-the-past have Seven years ago UC Davis and the dominated Delta discussions to date. engaging and passionate about Santa Public Policy Institute of California Monica Bay and has a good relation- Fortunately, the intractable nature raised awareness of how climate of the problem lies with us, not with ship with Los Angeles County, which change and earthquakes posed a sig- helped get things done.” JE nature. There are many “sure bets” we nificant threat to the sunken ‘islands’ can pursue now while we develop broad Cover photo: Spring bloom of lupine in the of the delta. This sparked an inten- public support for long-term action. Mt. Tam watershed by Jacoba Charles. sive study of levee vulnerability and a 3 species sci E nc E SPOT Clams Muddle Delta Restoration Boosting phytoplankton growth is a toplankton is overgrazed by two small Stalking the key part of the Bay Delta Conservation invasive clams. Plan, as the supply of these tiny algae Tiger Beetle Photo: Brian Chambers The half-inch overbite clam, Potamocor- at the base of the Delta’s food web has As you walk along a muddy creek- bula amurensis, is infamous for grazing plunged over the last few decades. bank or the edge of a salt pond, life- voraciously in the saltier zones of the According to conventional wisdom, the and-death struggles may be happening Estuary. In the fresh waters best way to increase phy- almost underfoot. Tiger beetles, small of the Delta, however, the toplankton is to create (up to 15 mm long) voracious preda- culprit is the roughly 2-inch shallow, slow waters to tors, haunt these habitats. The speedy give algae plenty of light, Asian clam, Corbicula fluminea, adults capture solitary bees, brine flies, as well as the chance to which was introduced in the ants, and smaller beetles. Larvae are build up over time. But 1940s. burrow-dwelling ambushers, popping recent research upends While it makes intuitive up like lethal Jack-in-the-boxes. In this approach for ecosys- sense that phytoplankton turn, the beetles are eaten by snowy tems that, like the Delta, will increase if there is plovers and burrowing owls. Their shiny have been invaded by more optimal algae habi- metallic coloration has won them a fol- exotic clams. tat, Lucas and Thompson found that lowing among beetle enthusiasts. But “For many, this is a new way of this can backfire in parts of the Delta they’ve been hit hard by development, thinking,” says US Geological Survey that have been invaded by the Asian and today the Bay’s tiger beetle com- engineer Lisa Lucas, who reported clam. This species can actually graze munity is on the edge of extirpation. this work with colleague Janet Thomp- too fast for phytoplankton to keep up, Wes Maffei of the Napa County Mos- son in the December 2012 issue of even in the shallow, still waters that quito Abatement District, who based favor algae. the journal Ecosphere. “Clams flip the the tiger beetle account in the 2000 Bay- ingrained model on its head.” To see if the conventional wisdom land Ecosystem Species and Community Profiles The phytoplankton decline is mir- held when Asian clams were present, on his local surveys, says four species rored by fish declines in the Delta, the team developed two simple math- once inhabited the Central and South suggesting that the two are linked.