Researchers are applying a novel genetic technique as part of the development of an annual estimate for the number of juvenile spring-run Chinook salmon entering the Delta.
The technique, spearheaded by geneticist Melinda Baerwald from the California Department of Water Resources, allows researchers to accurately distinguish young spring-run salmon from other runs by targeting DNA sequences specific to these fish. In a paper published in San Francisco Estuary and Watershed Science, lead authors Baerwald and Peter A. Nelson explain some of the challenges of developing this estimate, called the spring-run juvenile production estimate. A key hurdle is differentiating spring-run fish from salmon that migrate during other seasons. Unlike juvenile salmon from the winter run, spring-run juveniles are hard to identify using the conventional length-at-date approach, which determines age and spawning migration season based on size. “There’s nothing visually about a spring-run salmon that distinguishes it...Read More
The Sacramento-San Joaquin Delta contains more than 50 peat islands. Most have subsided—some as much as three meters — as a result of drainage for farming, and must maintain artificial water tables below the land surface via managed pumping. According to researchers from the University of California at Santa Cruz and the US Geological Survey, these pump stations are an underappreciated source of nutrients in nearby waters, with potentially significant implications for habitat and water quality. To get a sense of how much nitrogen is leaving the islands and when, the researchers measured monthly discharge along with nutrient and trace element concentrations in drainage from three Delta islands over the course of nearly a year and a half, then...Read More
Several projects in the lower Sacramento River and Delta have been exploring strategies for increasing the quantity and quality of food for migratory and resident fish. As part of a broader whole-ecosystem experiment that added nitrogen into the Sacramento River Deep Water Ship Channel, Leah K. Lenoch and colleagues at USGS and UC Davis looked into the channel’s hydrodynamics to explore whether the environmental conditions there hold promise for increasing the quantity of phytoplankton (the microscopic algae at the base of the food web). They knew that turbid and well-mixed waterways, including parts of the San Francisco Estuary and Delta, are not very productive because phytoplankton don’t get enough light and are at the mercy of invasive clams. However, where...Read More
In the mountains and foothills of California, an enduring drought has depleted the state’s major reserves of water. There is virtually no snowpack, and most of the state’s large reservoirs are less than 40 percent full. But in the central Sierra Nevada, a trio of artificial lakes remain flush with cold mountain water. The largest of them, Hetch Hetchy Reservoir, from which millions of Bay Area residents receive water, is more than 80 percent full. This remarkable plentitude is the outcome of careful planning by the agency that manages the Yosemite National Park reservoir plus conservation by Bay Area residents, who use less water per capita than most other people in the state—between 35 and 65 gallons per person per...Read More
The success of a restoration project is in the eye of the beholder. Take the recently revitalized salt marsh edging Drift Creek in Alsea Bay, Oregon. To ecologists, the sight of new channels winding through bare, brown mud is a thing of beauty, heralding the abundance of life to come, from sedges and rushes to fish and shorebirds. But, as researchers learned while speaking with people living nearby, not everyone shares this view. Some locals favored the unrestored side for its lush green vegetation and vistas of grazing elk. Resolving such differences in perception is key to local support, which can be required for project funding and permitting. “Restoration can look unsightly at first,” said UC Davis salt marsh ecologist...Read More
Jessica Rudnick’s first love was earth science. But after discovering that people’s beliefs and behaviors were key to solving environmental problems, she fell for social science. Now, as the California Sea Grant extension specialist for the Delta, Rudnick is working to better integrate local people into plans for the region. Understanding the needs of people who live, work, and recreate in the Delta could make the difference between fixes that are rejected or embraced. Delta planning has historically focused largely on ecological health. But, like many estuarine areas, the Delta is a lived-in landscape. “There are socially embedded challenges that play out in environmental issues,” she says. “You can’t just throw more data and research at a problem and think...Read More
California’s disappointing history of salmonid recovery programs has motivated a group of scientists from public water agencies and environmental conservation groups to step back, dream big, and take a new path forward. This group wants to abandon familiar heated dialogues and litigious relationships and try a new approach toward fish recovery based on collaboration, common interests and science.Read More
Morning at Suisun Marsh is a living watercolor with a soundtrack. Miles of tule and pickleweed populate the foreground, split by canals glinting silver from the sun. In May, the hills undulate across the northern boundary in classic California gold. A red-tailed hawk’s iconic hoarse screech punctuates the insectine buzz as it takes off from a powerline. At 7:40 AM, it’s already 72 degrees and there’s no trace of a breeze. I’ve come to visit the Marsh from downtown Oakland seeking to learn from biologists, hunters, and land managers what’s at stake in the myriad battles with rising seas, worsening drought, and, especially, encroaching invasive species and what makes it such a singular, attractive landscape. Indeed, the pastoral foreground is...Read More
Dutch Slough in Oakley, on the southern edge of the Sacramento-San Joaquin Delta, is less than a mile from where biometeorologist Dennis D. Baldocchi (above) grew up on his parents’ orchard and fished with pals in nearby Marsh Creek. In October 2021, the California Department of Water Resources breached the levees here, restoring nutrient-rich tidal flows to degraded ranchland. Early in the 20th century, Baldocchi’s father grew dry beans and sugar beets on the peat soils of the Delta’s Liberty Island, and his aunt’s family raised asparagus, sugar beets, and corn on Sherman Island. In 1952, his dad started growing almonds and walnuts at the junction of Sellers Avenue and Cypress Road in Oakley. “My family mined the Delta for...Read More
A novel exemption lawmakers passed to California’s landmark Environmental Quality Act (CEQA) in late 2021 has helped fast-track at least four habitat restoration projects so far, with more to follow in the next couple years. The Statutory Exemption for Restoration Projects, or SERP, offers a rare reprieve from California’s stringent environmental review and permitting process — and a clear indication of the urgency the state’s leaders feel in advancing ecological restoration work. “When [SERP] passed, it was a little bit controversial,” says Sara Johnson, executive director of the fledgling California Ecological Business Association. Sluggish regulatory approval timelines are the top grievance member organizations of the association share, she said at the Society for Ecological Restoration’s conference in Carmel Valley in...Read More
Why not richer rice fields, more wetlands, better boat launches, extended trails, even eco-tourism? ? A new survey for the Delta Islands Adaptation Project, funded by a Prop 1 Watershed Restoration Grant, wants the public’s opinion on the importance of 10 possible land-use objectives leading to the selection of one of the four islands for improvements. As your blinking cursor hovers over a satellite image of Bouldin, Bacon, Webb, and Holland Tracts, the survey lays out all that the experts know already: Holland is the least subsided; Bouldin the most accessible by road; Webb the best candidate for making more fish food, and more. “The Central Delta has some of the most critical landscapes in the state, and also some...Read More
The seasonal bias suggests flows were overestimated during the summer months and underestimated during the winter. Estimates of Delta outflow use a measurement called net Delta outflow index (NDOI), which is determined by taking the amount of Delta inflow, from sources such as the Calaveras, Sacramento, and San Joaquin rivers, and subtracting Delta exports, a direct measurement, and net Delta channel depletions. A team led by TetraTech’s Paul Hutton compared NDOI estimates against measured Delta outflow at four points, as well as against the Estuary’s historical salinity record. The study, which appears in the December 2021 issue of San Francisco Estuary and Watershed Science, focused on net Delta channel depletions, which are determined indirectly and involve considerations such as land...Read More
According to a new study published in San Francisco Estuary and Watershed Science, even surveys that target the same part of the water column can come up with significantly different catches. The study’s authors analyzed decades worth of data from the California Department of Fish and Wildlife (CDFW) Fall Midwater Trawl, which spans from San Pablo Bay to the upper Delta; CDFW’s San Francisco Bay Study midwater and otter trawls, covering the South Bay to the central Delta; and the UC Davis Suisun Marsh Fish Study, also an otter trawl. The two midwater trawls, which sample the middle of the water column, were found to be generally more successful at catching pelagic (open-water) fish like Delta smelt and American shad...Read More
A research team led by UC San Diego’s John Helly processed 15 years’ worth of water-use data from the state’s Department of Water Resources, reporting in the March 2022 issue of San Francisco Estuary and Watershed Science that while “the annually precipitated water supply in the Bay-Delta” varied by 30%, agricultural water use scarcely changed year to year. “The water management system maintained nearly constant agricultural water use even in periods of intense drought, with year-to-year variation of about 7%,” the authors wrote. Residential water use showed more variability, swinging by 20% from one year to the next–mainly, the authors theorize, as the result of voluntary and mandated water conservation during droughts. Though Helly says he had no expectations of...Read More
Once you know how many fish are present in a particular part of a river, including additional details like the time of day and water temperature, what do you do with this information? For decades, Delta researchers have collected millions of similar data points from daily visits to the San Francisco Estuary, not all of which are available or immediately useful. How that information is then translated into a language relevant to water and conservation managers requires serious number, or data, crunching. Sam Bashevkin, senior environmental scientist at the Delta Science Program in the Delta Stewardship Council, is working to bring data science to the San Francisco Estuary and help to make sense of the overwhelming data troves generated by...Read More
After two critically dry years that coincided with Trump-era rollbacks to environmental protections, some iconic Delta fish are closer than ever to the point of no return. Last fall, the fall midwater trawl found zero wild Delta smelt, while a coalition of environmentalists and fishermen is asking a federal court to help prevent a repeat of 2021’s near-obliteration of endangered winter-run Chinook salmon. Their lawsuit is just one of several projects....Read More
Twelve years ago, scientists at UC Davis began a survey of the southern end of San Francisco Bay — the Lower South Bay — to see how fish responded to the South Bay Salt Ponds Restoration Project. They discovered an unexpectedly diverse and robust aquatic community and a previously unknown spawning ground for the longfin smelt (Spirinchus thaleichthys), listed as endangered in California and a candidate for federal protection because of its declining numbers. The team, led first by Jim Hobbs and now by Levi Lewis, has complied an invaluable long-term dataset and enhanced our understanding of the surprising ecosystems of the bottom of the Bay. In addition to journal publications, their findings have been shared in blog posts by...Read More
As a source of flowing water, upper Coyote Creek is unreliable at best. Though storms swell its banks in winter, Mediterranean-climate summers shrink this South Bay stream to a series of isolated pools by August. “By October right before the rains come, we’re down to these really small pools that have all the fish in them,” says retired U.S. Environmental Protection Agency ecologist Rob Leidy. Leidy and UC Berkeley fish ecologist Stephanie Carlson began monitoring the annual dry-down of upper Coyote Creek in 2014, with the help of Hana Moidu and other graduate students. The creek itself originates in Henry W. Coe State Park and flows to the Bay through Coyote and Anderson lakes south of San Jose. The scientists...Read More
I started sampling the fishes of Suisun Marsh in 1979 because one of my UC Davis graduate students was looking for a place to study tule perch, a live-bearing native fish. We found not only a lot of tule perch in the marsh, but also an abundance of other native fishes. Clearly, this was a good place to study species for which we had little information at that time. Two things helped with our new project. First, sampling boats could be launched less than an hour’s drive from campus. Second, the California Department of Water Resources needed a study to examine effects of new tidal gates on fish. The gates are designed to retain fresher water in the marsh to...Read More
A 90-year-old Australian lungfish at San Francisco’s Academy of Sciences has received a lot of press lately, but there is a wild fish species living in the San Francisco Bay that has the potential to live that long or longer — or so we think. While one white sturgeon caught in the Columbia River Basin was estimated to be 104 years old, the life expectancy of white sturgeon, Acipenser transmontanus, which includes the Central Valley population endemic to the San Francisco Bay, is hard to pin down. “There are old ones out there, but it’s really hard to give a number because we just don’t have it,” says John Kelly, statewide sturgeon coordinator for the California Department of Fish and...Read More
Nothing could be stranger than sitting in the dark with thousands of suits and heels, watching a parade of promises to decarbonize from companies and countries large and small, reeling from the beauties of big screen rainforests and indigenous necklaces, and getting all choked up.
It was day two of the September 2018 Global Climate Action Summit in San Francisco when I felt it.
At first I wondered if I was simply starstruck. Most of us labor away trying to fix one small corner of the planet or another without seeing the likes of Harrison Ford, Al Gore, Michael Bloomberg, Van Jones, Jerry Brown – or the ministers or mayors of dozens of cities and countries – in person, on stage and at times angry enough to spit. And between these luminaries a steady stream of CEOs, corporate sustainability officers, and pension fund managers promising percentages of renewables and profits in their portfolios dedicated to the climate cause by 2020-2050.
I tried to give every speaker my full attention: the young man of Vuntut Gwichin heritage from the edge of the Yukon’s Arctic National Wildlife Refuge who pleaded with us not to enter his sacred lands with our drills and dependencies; all the women – swathed in bright patterns and head-scarfs – who kept punching their hearts. “My uncle in Uganda would take 129 years to emit the same amount of carbon as an American would in one year,” said Oxfam’s Winnie Byanyima.
“Our janitors are shutting off the lights you leave on,” said Aida Cardenas, speaking about the frontline workers she trains, mostly immigrants, who are excited to be part of climate change solutions in their new country.
The men on the stage, strutting about in feathers and pinstripes, spoke of hopes and dreams, money and power. “The notion that you can either do good or do well is a myth we have to collectively bust,” said New Jersey Governor Phil Murphy whose state is investing heavily in offshore wind farms.
“Climate change isn’t just about risks, it’s about opportunities,” said Blackrock sustainable investment manager Brian Deese.
But it wasn’t all these fine speeches that started the butterflies. Halfway through the second day of testimonials, it was a slight white-haired woman wrapped in an azure pashmina that pricked my tears. One minute she was on the silver screen with Alec Baldwin and the next she taking a seat on stage. She talked about trees. How trees can solve 30% of our carbon reduction problem. How we have to stop whacking them back in the Amazon and start planting them everywhere else. I couldn’t help thinking of Dr. Seuss and his truffala trees. Jane Goodall, over 80, is as fierce as my Lorax. Or my daughter’s Avatar.
Analyzing my take home feeling from the event I realized it wasn’t the usual fear – killer storms, tidal waves, no food for my kids to eat on a half-baked planet – nor a newfound sense of hope – I’ve always thought nature will get along just fine without us. What I felt was relief. People were actually doing something. Doing a lot. And there was so much more we could do.
As we all pumped fists in the dark, as the presentations went on and on and on because so many people and businesses and countries wanted to STEP UP, I realized how swayed I had let myself be by the doomsday news mill.
“We must be like the river, “ said a boy from Bangladesh named Risalat Khan, who had noticed our Sierra watersheds from the plane. “We must cut through the mountain of obstacles. Let’s be the river!”
Or as Harrison Ford less poetically put it: “Let’s turn off our phones and roll up our sleeves and kick this monster’s ass.”
4th California Climate Change Assessment Blues
by Isaac Pearlman
Since California’s last state-led climate change assessment in 2012, the Golden State has experienced a litany of natural disasters. This includes four years of severe drought from 2012 to 2016, an almost non-existent Sierra Nevada snowpack in 2014-2015 costing $2.1 billion in economic losses, widespread Bay Area flooding from winter 2017 storms, and extremely large and damaging wildfires culminating with this year’s Mendocino Complex fire achieving the dubious distinction of the largest in state history. California’s most recent climate assessment, released August 27th, predicts that for the state and the Bay Area, we can expect even more in the future.
The California state government first began assessing climate impacts formally in 2006, due to an executive order by Governor Schwarzenegger. California’s latest iteration and its fourth overall, includes a dizzying array of 44 technical reports; three topical studies on climate justice, tribal and indigenous communities, and the coast and ocean; as well as nine region-specific analyses.
The results are alarming for our state’s future: an estimated four to five feet of sea level rise and loss of one to two-thirds of Southern California beaches by 2100, a 50 percent increase in wildfires over 25,000 acres, stronger and longer heat waves, and infrastructure like airports, wastewater treatment plants, rail and roadways increasingly likely to suffer flooding.
For the first time, California’s latest assessment dives into climate consequences on a regional level. Academics representing nine California regions spearheaded research and summarized the best available science on the variable heat, rain, flooding and extreme event consequences for their areas. For example, the highest local rate of sea level rise in the state is at the rapidly subsiding Humboldt Bay. In San Diego county, the most biodiverse in all of California, preserving its many fragile and endangered species is an urgent priority. Francesca Hopkins from UC Riverside found that the highest rate of childhood asthma in the state isn’t an urban smog-filled city but in the Imperial Valley, where toxic dust from Salton Sea disaster chokes communities – and will only become worse as higher temperatures and less water due to climate change dry and brittle the area.
According to the Bay Area Regional Report, since 1950 the Bay Area has already increased in temperature by 1.7 degrees Fahrenheit and local sea level is eight inches higher than it was one hundred years ago. Future climate will render the Bay Area less suitable for our evergreen redwood and fir forests, and more favorable for tolerant chaparral shrub land. The region’s seven million people and $750 billion economy (almost one-third of California’s total) is predicted to be increasingly beset by more “boom and bust” irregular wet and very dry years, punctuated by increasingly intense and damaging storms.
Unsurprisingly, according to the report the Bay Area’s intensifying housing and equity problems have a multiplier affect with climate change. As Bay Area housing spreads further north, south, and inland the result is higher transportation and energy needs for those with the fewest resources available to afford them; and acute disparity in climate vulnerability across Bay Area communities and populations.
“All Californians will likely endure more illness and be at greater risk of early death because of climate change,” bluntly states the statewide summary brochure for California’s climate assessment. “[However] vulnerable populations that already experience the greatest adverse health impacts will be disproportionately affected.”
“We’re much better at being reactive to a disaster than planning ahead,” said UC Berkeley professor and contributing author David Ackerly at a California Adaptation Forum panel in Sacramento on August 27th. “And it is vulnerable communities that suffer from those disasters. How much human suffering has to happen before it triggers the next round of activity?”
The assessment’s data is publicly available online at “Cal-adapt,” where Californians can explore projected impacts for their neighborhoods, towns, and regions.